Ophthalmologist Bates Cures Unclear Eyesight

Quantum Vision System

The Quantum Vision System is an overall package to heal and thereby improve vision all together. The step by step guide and the instructional videos contain lots of information regarding the dos and don'ts to protect eyes from further damage. The program is not based on the treatment but also saves us from damaging vision with the use of lenses or glasses. The 3 in one package contains methods to nourish, cleanse, and effectively improve the vision with simple exercise. The eye chart provided is to be used to track the vision improving progress. According to the treatment program, Quantum Vision System can be used to treat various eye problems like Myopia or Near sightedness, Hyperopia or Farsightedness, Prebyopia, Dyslexia, Macular Degeneration, Lazy Eye or Amblyopia, Astigmatism, Cataract, Glaucoma, Tension Headache and Eye strain. The program can treat visual problems within 2 to 3 months.

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American Academy of Ophthalmology Clinical Education Secretariat Louis B Cantor MD Indiana University School of

Glaucoma Surgery Principles and Techniques, second edition Edited by Robert N. Weinreb and Richard P. Mills 7. Cataract Surgery and Intraocular Lenses A 21st-Century Perspective, second edition Edited by Jerry G. Ford and Carol L. Karp 12. Low Vision Rehabilitation Caring for the Whole Person Edited by Donald C. Fletcher 13. Glaucoma Medical Therapy Principles and Management, second edition Edited by Peter A. Netland

TABLE 4 Eye Disease in GCA

A retrospective study of eye disease occurring in 161 patients over a 17-year period provides a useful perspective of this complication (15). Visual manifestations occurred in about 26 of patients, and loss of vision in at least one eye occurred in about 15 (Table 4). Twenty-four patients had permanent vision loss in 92 of these, anterior ischemic optic neuritis was the cause. Central retinal artery occlusion occurred in 8.3 of patients as the cause of permanent visual loss, and occipital infarction caused by vertebral basilar stroke occurred in one patient (4.2 ). These authors noted that patients positive for HLA-DRB1 * 04 had visual manifestations more commonly than those who did not the phenotype was found in 42 of patients versus 26 of controls (15).

Discrete Openangle Glaucomas

The term ''primary open-angle glaucoma'' refers to a condition characterized by elevated IOP and characteristic optic disk and or visual field damage with no other identifiable cause at slit-lamp examination. However, the use of the word ''primary'' is suggestive of a single, discrete entity with a specific mechanism of disease causation. More likely, this category represents an assortment of disorders, as we are now seeing with the discovery of multiple genetic loci. Similarly, the term ''normaltension glaucoma'' (or ''low-tension glaucoma'') has been used to define a group of patients with glaucomatous damage but IOP less than some arbitrarily defined number. This is an artificial distinction based on population statistics. Interpretation of this term as previously used in the literature is further complicated by the recent realization that Goldmann tonometry is influenced by corneal thickness, a factor not routinely measured previously. The term ''idiopathic open-angle glaucoma,''...

Models of Age Related Vision Problems

The visual system provides unique opportunities to study the aging process, as well as challenges in understanding and developing therapies for age-related eye diseases. Exposure of the lens to high levels of photo-oxidative stress and the lack of protein turnover in the lens nucleus make it an optimal system in which to study protein modifications in aging. Similarly, the high level of metabolic activity in the retina and the necessity for turning over large amounts of lipids provide particular research opportunities as well. Finally, visual diseases associated with aging are among the most common threats to the quality of life in the elderly. Of age-related visual diseases, three result in a particularly high burden on the population age-related cataracts, age-related macular degeneration, and progressive open angle glaucoma. Thus, these are dealt with in some detail in this brief review. Because of space and formatting limitations, much work described in this review could not be...

Human Studies On Agerelated Cataracts

Linkage studies In addition to epidemiological evidence implicating genetic factors in age-related cataracts, a number of inherited cataracts with post-infantile age of onset or progression of the opacity throughout life have been described. Mutations in beaded filament specific protein 2 (BFSP2) can cause juvenile cataracts, the Marner and Volkmann cataracts can be progressive, mutations in aquaporin 0 (MIP) and yC-crystallin can cause progressive cataracts, and the CAAR locus is linked to familial adult onset pulverulent cataracts. These all suggest that for at least some genes, a mutation that severely disrupts the protein or inhibits its function might result in congenital cataracts inherited in a highly penetrant Mendelian fashion, whereas a mutation that causes less severe damage to the same protein or impairs its function only mildly might contribute to age-related cataracts in a more complex multifactorial fashion. Similarly, mutations that severely disrupt the lens cell...

Biochemical Studies Of Agerelated Cataracts

Crystallin modifications associated with cataracts The lens crystallins are a major potential target for accumulating damage associated with age-related cataracts, although there are certainly others. Thus, as the crystal-lins accumulate modifications and damage over the lifetime of an individual, their ability to participate in appropriate intermolecular interactions, and even to remain in solution, decreases. Whether proteins in age-related cataracts become insoluble as a result of complete or partial denaturation, or whether they simply become less soluble due to modifications that leave their protein folds largely intact or both, is not currently known. However, it seems clear that modifications to crystallin proteins accumulate with aging and accelerate during cataractogenesis, and the combination of crystallin modification, disulfide-crosslinking, denaturation, and aggregation results in loss of lens transparency and cataract formation (Hanson et al., 2000). The protein...

Glaucoma Medical Therapy In Pregnancy

Although glaucoma is infrequently diagnosed in pregnant patients, occasionally patients with preexisting glaucoma become pregnant. Whenever medications are prescribed for glaucoma, the clinician considers the potential for systemic effects on the patient. In pregnant women, this concern extends to the developing child, as well. One major advantage to the use of topical medications for glaucoma is the reduced systemic absorption and coincident decrease in systemic symptoms. There is little literature demonstrating adverse events of topical medications during pregnancy.1,2 13.1.2 Natural History of Intraocular Pressure During Pregnancy. Metabolic and physiologic changes during pregnancy cause a mild decrease in the intraocular pressure (IOP) compared to the pressure before pregnancy. This has been proposed to occur by several mechanisms. The episcleral venous pressure decreases due to changes in the mother's hemodynamics. A metabolic acidosis occurs, which...

Glaucoma Medical Therapy During Lactation

There are few studies in the literature regarding the safety of glaucoma mediations during breast-feeding. Any medication with any degree of systemic absorption must be assumed to have a measurable level in breast milk. Due to the extreme reluctance to used any medications in pregnant and lactating women, these data are difficult to Pregnancy and Pediatric Patients 235 Table 13.1 FDA Category Classifications for Glaucoma Medications

Glaucoma Medical Therapy In Pediatric Patients

Children are more vulnerable to side effects, due to reduced body mass and blood volume for drug distribution (resulting in higher concentrations from the same absorbed dose). Also, they may be unable to verbally describe side effects caused by medications. Thus, children on chronic medical therapy need to be carefully monitored. The medical regimen must be frequently reevaluated in an effort to use the minimum medical regimen that will result in acceptable IOP control. Glaucoma medications commonly used in children are shown in table 13.2. 13.3.2.1 Prostaglandin analogs. In pediatric patients, latanoprost has been evaluated in a variety of diagnoses including Sturge-Weber syndrome.11-14 In one study of 31 eyes, 19 had a 34 reduction in IOP.15 The majority of the eyes did not respond to the therapy (figure 13.1).15 Juvenile-onset open-angle glaucoma was more likely to respond, most likely due to the anatomy of the angle more closely approximating that in...

Prevention Of Cataracts

Numerous observational and prospective clinical studies have been performed to examine the effect of vitamin C alone or in combination with other antioxidants on cataract. Several epidemiological studies have identified an association between vitamin C and cataract incidence (Ferrigno et al 2005, Jacques & Chylack Jr 1991, Jacques et al 1988, Valero et al 2002) however, studies investigating whether supplementation is protective have produced mixed results (Chasan-Taber et al 1999, Chylack Jr et al 2002, Hammond & Johnson 2002, Jacques et al 1997, 2001, Kuzniarz et al 2001, Seddon et al 1994, Taylor et al 2002).

Primary open angle glaucoma

Risk factors in POAG include ones related to onset and others related to progression. Age is a major risk factor, with prevalence rising steeply from < 0.1 before age 30 years to 5-10 or greater in the elderly (Johnstone and Quigley, 2003). A major risk factor for both disease onset and progression is IOP, which in Europeans has a mean of 16 mm Hg and standard deviation of 2.5 mm Hg, but since the distribution is non-normal, 5-7 (rather than 2.5 ) of the population has IOP greater than 21 mm Hg, which is often regarded as the upper limit of normal. The risk of glaucoma rises with increasing IOP, following a shallow exponential curve with no evident threshold. In addition, there is a normal diurnal variation of 5 mm Hg that can reach even higher levels in glaucoma. The higher the IOP, the greater the risk of optic nerve damage, and lowering of IOP has been shown to be beneficial in glaucoma whether or not it is elevated (Heijl et al., 2002). Other risk factors for POAG include myopia...

Primary angle closure glaucoma

Little is known about the molecular basis of the disease in this, the commonest, form of glaucoma in East or South East Asian populations. It results from permanent closure of the filtration angle as a result of iris apposition to the trabecular mesh-work. It tends to occur in short hypermetropic (long-sighted) eyes with an anteriorly placed lens. The prevalence increases with age and in the presence of a family history and females are more often affected than males, but specific causal factors remain unknown.

Ophthalmic Diseases

AAV vectors may be well suited for efficient long-term treatment of ocular diseases because they efficiently and stably transduce retinal pigment epithelium and photoreceptor cells following subretinal injection (93,252-257). Retinitis pigmentosa (RP) is a group of inherited retinal degenerative diseases that lead to progressive reduction in visual field extent and impairment of visual acuity. The disease is triggered by mutations in various genes that cause degeneration and death of photoreceptors by apoptotic pathways (258). Control of angiogenesis in the retina is essential to the preservation of vision. Ocular neovascularization (NV) is a major threat to vision and a complicating feature of many eye diseases, including proliferative diabetic retinopathy, age-related macular degeneration, and retinopathy of prematurity. Regulation of vascularization in the mature retina involves a balance between endogenous positive growth factors (e.g., vascular endothelial growth factor), and...

Animal Models Of Agerelated Cataracts

Since cataractogenesis is a complex process accompanied by numerous secondary changes, animal models may provide useful information for delineating the causes of senescent and other cataracts. Hereditary cataracts in rodents have been especially useful in this regard (Graw and Loster, 2003). One example is the Philly mouse, which displays an autosomal dominant cataract in which there is a deficiency of B2-crystallin polypeptide. The B2-crystallin mRNA has a deletion of 12 nucleotides, resulting in a four-amino-acid deletion in the encoded protein. It has been hypothesized that this causes aberrant folding of the protein and that cataract formation occurs as a result of the molecular instability of this crystallin and is therefore a good model to examine the roles of crystallin proteolysis and aggregation in age-related cataract formation. Other models suggest that some metabolic lesions can also cause cataracts. The Nakano mouse, which has autosomal recessive cataracts mapping to...

Angleclosure Glaucoma

Angle closure is an anatomic disorder comprising a final common pathway of iris apposition to the trabecular meshwork. By recent convention, the term glaucoma is applied to eyes with visual field and or optic nerve damage, analogous to the differentiation between ocular hypertension and glaucoma in eyes with open angles. Angle closure results from various abnormal relationships of anterior segment structures. These, in turn, result from one or more abnormalities in the relative or absolute sizes or positions of anterior segment structures or posterior segment forces that alter anterior segment anatomy.1 Angle closure results from blockage of the meshwork by the iris, but the forces causing this blockage may be viewed as originating at four successive anatomic levels (figure 12.1) 3. Lens (phacomorphic glaucoma) 4. Posterior to lens (aqueous misdirection, or malignant glaucoma) Figure 12.1. (A) Pupillary block (level 1). Force-producing iris apposition to the trabecular meshwork...

Glaucoma Treatment Trials

Treatment of POAG and other forms of open-angle glaucoma has been addressed by several large clinical trials comparing medical, laser, and surgical intervention. Two of these trials assessed early surgical intervention. In the Scottish Glaucoma Trial,20 99 patients with newly diagnosed glaucoma were randomly assigned to initial trabeculectomy (46 patients) or conventional medical therapy followed by trabeculectomy if medical therapy failed (53 patients). After a 3- to 5-year follow-up, a greater decrease in IOP was noted in those treated with surgery. More than half of those treated with medical therapy required surgical intervention. There was no difference in final visual acuity between the two groups, but there was greater visual field loss in the medically treated group. The Moorfields Primary Treatment Trial21 randomized 168 newly diagnosed glaucoma patients into three groups initial medical therapy, initial laser trabeculoplasty, or initial trabeculectomy. With a minimum...

Visual Acuity Measurement

The accurate assessment of visual function is an important part of the neuro-ophthalmic exam. Many of the entities in subsequent chapters have decreased visual acuity as the presenting symptom. Special techniques are required to obtain an objective assessment of visual function in the young child. Table 2-1 contains a summary of the methods applicable to the various age groups. Binocular visual acuity should be evaluated first because it is often superior to monocular function and the manipulation TABLE 2-1. Visual Acuity Testing by Age. required to test the vision monocularly may result in loss of cooperation. Near visual function testing should also be attempted because in most neuro-ophthalmic disorders visual acuity will be better at near than at distance. This point is extremely important when trying to assess whether the child will be able to attend regular schools and whether large-print books or other visual aids will be necessary.

Peripheral Vision

Record the patient's visual fields with his right eye field on your right. Mark his right field with Rt. and his left field with Lt. Indicate central vision with a plus sign. Add the visual acuity (corrected or uncorrected), date, and shade the blind areas. Figure 1-7. Record the patient's visual fields with his right eye field on your right. Mark his right field with Rt. and his left field with Lt. Indicate central vision with a plus sign. Add the visual acuity (corrected or uncorrected), date, and shade the blind areas. When making notes about visual fields, draw the patterns in the patient's history as though they were your own fields (Figure 1-7), that is, the right eye field on your right and the left eye field on your left. Include the visual acuity and date.

Cataracts

Although a high intake of beta-carotene containing foods has been associated with the prevention of cataracts, the role of supplementation is uncertain. An assessment of dietary beta-carotene intake in a subgroup of 472 non-diabetic women, aged 53-73 years, who participated in the Nurses' Health Study found that the odds of posterior subcapsular cataracts was 72 lower in those with the highest intakes of beta-carotene who had never smoked, whereas beta-carotene intake and cataract risk were not associated in current or past smokers (Taylor et al 2002). This finding is contrasted with findings from intervention studies that have found that beta-carotene may help prevent cataracts in smokers (Christen et al 2003, 2004). Two years of beta-carotene treatment was found to have no large beneficial or harmful effect on the development of cataract in a randomised, double-masked, placebo-controlled trial of 39,876 female health professionals aged 45 years or older who participated in the...

Eye Strain

A double-blind study involving 75 patients with eye strain caused by viewing a computer screen found that GSE 300 mg daily significantly improved objective and subjective measures (Bombardelli & Morazzoni 1995). Grapeseed extract (Endotelon' ) has also been shown significantly to improve visual adaptation to and from bright light in a dual centre study involving 100 volunteers (Boissin et al 1998, Corbe et al 1988). A dose of 200 mg daily over 5 weeks was used. It has been proposed that GSE increases rhodopsin content of the retina or accelerates its regeneration after exposure to bright light.

Trauma And Glaucoma

Surgical intervention is warranted when IOP cannot be controlled medically and threatens to cause glaucomatous damage or if corneal blood staining develops. Unfortunately, the optic disk usually cannot be visually assessed, and many patients will manifest afferent pupillary defects caused by the presence of the blood itself, rather than by the optic nerve injury. Consequently, intervention may need to be undertaken based on somewhat arbitrary criteria. Although a healthy optic nerve may be able to tolerate IOP of 40 to 50 mm Hg for 1 week or longer, a glaucomatous disk may suffer further damage with substantially lower IOP within a shorter time period. Evaluation of the fellow eye for evidence of preexisting glaucomatous optic neuropathy may thus be helpful with regard to guiding therapy. 12.3.2 Angle-Recession Glaucoma. Angle-recession glaucoma usually develops years or even decades after blunt trauma with hyphema. In one series, the mean duration between injury and diagnosis of...

Glaucoma

Glaucoma is a diverse group of progressive optic nerve disorders (neuropathies) which accounts for 12 of global blindness, second only to cataract (Resnikoff etal., 2004). In Western countries, where cataract-related blindness is substantially less common (about 5 of blindness), glaucoma is also the second most common cause, accounting for 18 of all blindness (Resnikoff etal., 2004). The diagnosis of adult-onset glaucoma is primarily based on characteristic structural abnormalities of the optic nerve head (optic disc Figure 32.1) together with functional abnormalities in the associated field of vision (Johnstone and Quigley, 2003). In the majority of cases, raised intra-ocular pressure (IOP > 99.5th percentile) is also present, but this is no longer regarded as necessary for the diagnosis, since one-sixth to one-third of patients have normal IOP. Raised IOP is certainly a major risk factor for glaucoma and genetic studies (see below) suggest that in some families it is a primary...

Agerelated cataract

Fovea Blood Pressure

The commonest cause of visual impairment globally is cataract, which is defined as opacity or loss of transparency within the crystalline lens, leading to reduced vision (Figure 32.1). This occurs when the refractive index of the lens varies over distances similar to the wavelength of light (Delaye and Tardieu, 1983). The causes of cataract are many and varied but include changes in lens cell architecture or in its protein constituents. For example, light scattering can result from aggregates in the size range of 100 nm or greater. About 37 million people worldwide are blind and over 160 million visually impaired (Resnikoff et al., 2004). The proportion of the population with severe visual impairment rises steeply with age, but the causes differ between continents and countries, varying from 0.1-0.2 in industrialized countries to over 1 in sub-Saharan Africa (Resnikoff et al., 2004). About 90 of the world's blind live in developing countries, where the major cause of blindness is...

Autonomy and Protection of Older Adults in Research How Much Is Enough

Some older adults, due to conditions commonly associated with aging, are capable of informed consent, but require additional accommodation to exercise it. Older adults typically undergo changes that may affect the informed consent process. Changes in vision and hearing are among them. More than 37 of noninstitutionalized persons 65 and over report trouble hearing and 17.5 report trouble seeing (National Center for Health Statistics, 2002). Visual acuity, color discrimination, and sensitivity all tend to decrease with age (Fozard et al., 2001). These changes are sufficiently prevalent among the aging that they should be routinely considered in informed consent by older adults. The changes are typically moderate and their onset gradual, so that persons adapt (through eyeglasses and hearing aids, avoiding noisy restaurants, taking additional time for decision-making, etc.) and continue to lead autonomous lives. Accommodating these needs in the informed consent process is ethically...

Agerelated Macula Degeneration

A high intake of beta-carotene-containing foods has been associated with the prevention of ARMD and observational and experimental data suggest that carotenoid supplements may delay progression of both ARMD and vision loss. This is supported by the findings from the ARED Study, an 11 -centre, double-masked clinical trial involving 3640 participants with ARMD that found supplementation with vitamin C 500 mg, vitamin E 400 IU, beta-carotene 1 5 mg and zinc 80 mg for 6 years significantly reduced the development of advanced ARMD and moderate visual acuity loss (Kassoff et al 2001). Although beta-carotene and other nutrients may have been found to be beneficial for preventing ARMD, the carotenoids lutein and zeaxanthin appear to provide the most protection (see Lutein zeaxanthin monograph).

Special Therapeutic Situations 215

12.1 Angle-Closure Glaucoma, 215 12.2 Discrete Open-Angle Glaucomas, 221 12.2.1 Pigmentary Glaucoma, 222 12.2.3 Corticosteroid-Induced Glaucoma, 224 12.2.4 Neovascular Glaucoma, 225 12.3 Trauma and Glaucoma, 226 12.3.2 Angle-Recession Glaucoma, 226 12.4.3 Patients with Cataracts, 229

Meso American medicine

The Incas occupied the highlands along the west coast of what is now Peru. The Mayan culture occupied the Yucatan Peninsula and surrounding areas of Central America, and the Aztecs controlled the central plateaus of Central America. When Columbus, Cortez, and their compatriots arrived in the new world, the Meso-American cultures were exposed to several devastating diseases, including measles, smallpox, and chickenpox, which were more lethal than the military armaments the invaders brought. The Pre-Columbian Americans still lived in a Stone Age culture, but were highly sophisticated in their knowledge of mathematics, astronomy, and language. Among the most useful drugs discovered in the New World was the Cinchona bark (quinine), which was used to treat fevers, including malaria. Diseases were believed to be caused by supernatural, magical, and natural causes. Treatment was related to the cause (56). One of the sources of information about disease in Pre-Columbian...

Simon K Law And David A

Ocular medications have an important role in the treatment of glaucoma. Medications are usually considered the first line of treatment for glaucoma, and in most glaucoma patients medications alone can control their disease. Glaucoma medications lower intraocular pressure (IOP) by either reducing aqueous production or increasing aqueous outflow through either the conventional or the unconventional pathways. Frequently, multiple glaucoma medications are used in combination to adequately lower IOP. A clear understanding of the pharmaco-kinetics of these medications is important to knowing several details

Diurnal Birds Of Prey Falconiformes

The birds in the order Falconiformes are called raptors (RAP-ters), or birds of prey, meaning they hunt animals for food. The raptors in the order Falconiformes include hawks, eagles, Old World vultures (from Africa, Asia, and Europe), falcons, and secretary birds. These raptors hunt during the day, and have beaks and feet that are made for hunting. Their beaks have sharp hooks that can tear meat. Their legs are generally short, and their feet have long, curved claws called talons (TAL-unz) that can grab and kill prey. These raptors have excellent eyesight, and can see about eight times better than humans.

Complications And Prognosis

Uveitis has numerous complications, which often cause visual loss. Treatment of uveitis can also contribute to these complications. Glaucoma may arise from a pressure response to corticosteroid therapy cataracts may develop from long-term use of these agents. Appropriate management of these complications provides the best opportunity for avoiding adverse visual outcomes. Band keratopathy is a complication specifically associated with JRA and is treated by chelation and excimer laser (Fig. 1D). CME is the most common cause of decreased visual acuity in patients with posterior uveitis (Fig. 1E). Finally, other complications may result from systemic treatments (1,14,16). Prognosis is best in patients with anterior uveitis. In one study, 4 of patients with anterior uveitis lost at least 25 of visual acuity, while 43 and 40 of patients with posterior uveitis and panuveitis, respectively, developed this complication (2).

Falcons And Caracaras Falconidae

The birds in the falcon family are small to medium raptors (birds of prey). They include peregrines (PER-uh-grunz) , falconets, gyrfalcons (JERR-fal-kunz), merlins, kestrels, hobbies, and caracaras. They range in size from 5.5 to 25.6 inches (14 to 65 centimeters) from their beaks to the end of their tails. Like other raptors, falcons have sharp talons (claws) and hooked beaks, excellent eyesight, and pointed wings. Most falcons have feathers in shades of brown, black, white, and gray with some streaks or spots.

Structural Barriers To Care

Reported that the passage of Proposition 187 in California may have discouraged immigrants in Los Angeles County from seeking screening and or early treatment for tuberculosis infection. The passage of Proposition 187 was also found to be associated with a decrease in new walk-in patients at an ophthalmology clinic at a major public inner-city hospital in Los Angeles County (Marx et al 1996) and a decrease in patients at an STD clinic (Hu, et al., 1995). However, Loue and colleagues (in press) found no statistically significant difference in time between onset of gynecological illness and seeking of care, or length of time between seeking care and receipt of care among women of Mexican ethnicity of varying immigration statuses in San Diego County. Another study of immigrants of various nationalities, languages, and immigration statuses in Cuyahoga County, Ohio similarly found no effect of the reform laws on immigrants' ability to access care (Loue, et al., 2000). A high proportion of...

Prostaglandin Analogs

Prostaglandin (PG) analogs, originally introduced for glaucoma therapy in the United States with latanoprost in 1996, have rapidly become the most commonly used ocular hypotensive agents. As a class, PG analogs are the most effective topical agents currently available for lowering intraocular pressure (IOP).1-4 Four PG analogs are available for clinical use latanoprost (Xalatan 0.005 , Pfizer, New York, NY), travoprost (Travatan 0.004 , Alcon, Fort Worth, Tex.), bimatoprost (Lumigan 0.03 , Allergan, Irvine, Calif.), and unoprostone (Rescula 0.15 , Novartis Ophthalmics, Basel, Switzerland). All have similar structures and are prodrugs of prostaglandin F2a (PGF2a) analogs. The structures of these drugs are compared in figure 2.1. Latanoprost, travoprost, and unoprostone are ester prodrugs that are hydrolyzed by corneal esterases to become biologically active. Latanoprost and travoprost are selective agonists for the F2a prostaglandin (FP) prostanoid receptor. Bimatoprost has been...

Concomitant Strabismus

There are a number of possible causes of a concomitant strabismus. These include defects of innervation, refraction, and accommodation plus a genetic predisposition as well as a large group in which the cause is unknown. Common causes are imbalance of the near reflex (accommodative strabismus) and unilateral reduced vision in an infant or child.

Examination screening specific to children

Strabismus should be sought in all infants and toddlers by occlusion testing (not very sensitive), examining light reflexes and questioning parents, which must be taken very seriously. Amblyopia can be prevented by early recognition and treatment of strabismus by occlusion and surgery. Early referral is essential. Visual acuity. At birth and 2 months, eyes should be inspected and examined with an ophthalmoscope with a 3+ lens at a distance of 20-30 cm to detect cataracts and red reflexes. At 9 months gross vision should be determined by assessing ability to see common objects. Visual acuity should be formally assessed at school entry using Sheridan Gardiner charts.

Nervous system and sensory organs

Snake Vomeronasal Organ

Photoreceptors consist of rods and cones. These structures bear protein molecules that capture light energy and convert it to nerve signals. The rods function best in dim light, whereas the cones function best in bright light and provide higher resolution. Varying abilities to differentiate color depend on the possession of multiple visual pigments, each of which absorbs maximally at different wavelengths of light. Some reptiles, such as arboreal snakes, have keyhole pupils, which enhance binocular vision (similar images are formed simultaneously on both retinas of the two eyes), and a fovea, where high densities of cones on the retina provide high visual acuity. Slender head shape, especially an attenuated snout, confers considerable overlap of vision in the two eyes. The eyes of chameleons are unique among vertebrates in their degree of movement and ability to scan the environment. Each eye is located on a turret and moves independently of the other. The lens of the chameleon's eye...

Iop Reduction In Clinical Trials

Numerous clinical trials have demonstrated the efficacy of PG analogs in lowering IOP. Clinical trials with latanoprost,1'2'29'31'47'81 bimatoprost'1'2'44'48 and travo-prost1-3'49 have all shown that these drugs given once daily are more effective than timolol 0.5 given twice a day in reducing mean diurnal IOP in patients with ocular hypertension or glaucoma (figure 2.5). PGs have also been shown to be as effective or more effective and often better tolerated than other topical glaucoma Figure 2.5. Efficacy of PG analogs compared to timolol 0.5 twice daily in reducing IOP. (A) Latanoprost 0.005 once daily. Reprinted with permission from Camras CB. Comparison of latanoprost and timolol in patients with ocular hypertension and glaucoma a six-month masked' multicenter trial in the United States. United States Latanoprost Study Group. Ophthalmology. 1996 103 138-147. (B) Bimatoprost 0.03 once daily. Reprinted with permission from Higginbotham EJ5 Schuman EK5 Goldberg I et al. One-year...

Clinical Studies On Additivity

Because PG analogs have a different mechanism of action than other ocular hypo-tensive drugs, the IOP reduction from PGs can be expected to be additive to that of other glaucoma medications. Multiple clinical studies have demonstrated that the Fixed-combination products have the advantage of being more convenient and potentially less expensive for patients' and therefore have the potential advantage of improving patient compliance. They also reduce preservative exposure by decreasing the number of daily drops. Beta blockers and PG analogs are especially well suited for a fixed-combination product. Since nonselective beta blockers or PG analogs both are effective when given once daily' a fixed combination of these products given once daily does not compromise circadian efficacy based on the duration of action of each component. Other fixed combinations may be less effective since other glaucoma medications require more frequent administration to maintain efficacy' and a combination...

Other Routine Checks What Should Be Monitored

In patients with less than 200 CD4 cells l, we usually perform fundoscopies every three to six months to exclude CMV retinitis. Close cooperation with an HIV-experienced ophthalmologist is important. The better the CD4 cells, the less often fundoscopies are necessary. When CD4 counts have normalized, these can be

Financing the American Health Care System

Worry among older Americans in particular is the status of Medicare and Medicaid. In 1993, the Medicare program cost 150 billion and the Medicaid program, 102 billion (National Center for Health Statistics, 1995). Part A of Medicare is financed by a portion of the Social Security tax, and Part B (Supplemental Medical Insurance) is paid for by a monthly deduction from the applicant's Social Security check. However, a number of different services and supplies (custodial care, dentures, and routine dental care, eyeglasses, hearing aids, examinations to prescribe and fit them, nursing home care, prescription drugs, routine physical checkups and related tests) are not paid for by Medicare. In addition, a deductible amount and a percentage of the remaining cost of treatment must be paid by private insurance or from other private sources. Because Medicare pays less than half of the medical bills of older Americans, patients who cannot pay the remaining amount must look to either charity or...

How to Examine the Pupils

Near Reaction If the light reflex works, so will the near reflex. If one or both pupils do not react to light, ask the patient to look at the far wall and then at the tip of your pencil, which should be 5-10 cm in front of his nose. If his visual acuity is seriously compromised, ask the patient to look at the tip of his own finger held in front of his nose.

Physical characteristics

Digits on fore- and hindlimbs fused to a mitten-like structure from which only the 3.2-3.9 in (8-10 cm) long claws protrude. These allow branches to be gripped without expending muscular force. The number of digits on the forelimb distinguish Bradypus from Choloepus sloths. They would be better named, three- and two-fingered sloths, since both have three digits on the hindlimbs. There are eight or nine neck vertebrae (most species of mammal, even giraffes, have seven). This allows the head to be turned with a considerable range, an important advantage for an animal with otherwise rather limited flexibility. The testes are internal. There are no incisors or canine teeth and the simple, peg-like incisors lack enamel. Sloths have poor hearing, but fairly good eyesight and smell.

Causes and Types of Abnormal Pupils

Argyll-Robertson Pupils Argyll-Robertson pupils are usually bilateral and result from tertiary syphilis of the nervous system, diabetes, or the late signs of bilateral tonic pupils (see the section on Adie's Syndrome). The pupils are small, irregular, and unequal. They do not react to light, they do react to near vision, they respond poorly to mydriatics, and they do not dilate in the dark. However, they can be made to constrict even more by the use of mi-otics. The poor light response and good near response may be relative that is, the light response need not be absent, but is much less evident than the near response. Visual acuity is not impaired.

Pupillary Examination

A wealth of information can be learned from examination of the pupils. An attempt should first be made to determine whether the pupils react to light and, if so, how briskly A brisk constriction to light usually indicates good ocular and optic nerve function. A sluggish response, or no response at all, implies retina, optic nerve, or third nerve dysfunction. This assessment of pupil response to light can be helpful in localizing the site of visual loss, which is especially helpful in the child with possible cortical visual impairment (Fig. 2-3). Brisk pupillary reactions in a child with profound visual loss indicate a cortical etiology (Table 2-2).

Is achieving extreme old age worthwhile the centenarian phenotype

Independently functioning at age 92 (Hitt et al., 1999). Most subjects experienced a decline in their cognitive function only in the last three to five years of their lives (Perls, 1997 Silver et al., 1998). Upon further examination of the ages of onset for ten common age-associated diseases (hypertension, heart disease, diabetes, stroke, non-skin cancer, skin cancer, osteoporosis, thyroid condition, Parkinson's disease, chronic obstructive pulmonary disease and cataracts) among 424 centenarians (323 males and 101 females), the subjects were noted to fit into three morbidity profiles ''survivors,'' ''delayers'' and ''escapers'' (Evert et al., 2003). Survivors, individuals who were diagnosed with age-related illness prior to age 80, accounted for 24 of the male and 43 of the female centenarians (p 0.0009). Delayers, individuals who delayed the onset of age-related diseases until at least age 80, accounted for 44 of the male and 42 of female centenarians. Escapers, individuals who...

Vitamin A Deficiency Infection and Mortality in Developing Countries A Recurring Theme

Xerophthalmia has been the most bitter pill for me to swallow during 18 years of doctor's work in Indonesia. The over and over repeated experience of discovering a child, recently blinded, in the arms of the mother having to tell her that I now could nothing more to save its eyesight remembering that I could have done so with a few spoonsful of cod-liver oil some days ago these things still enter my nightmares. They belong to the most vivid examples of what disprivilegedpeople in underdeveloped regions sometimes miss More printing space nowadays is devoted to a few cases of hypervitami-nosis A, induced by an irresponsible vitamin racket, than to the thousands of small children who die or get blind every year due to the lack of a handful of vitamin A units. What on earth is nutritional science good for, if, even in the atom age, it is not capable to counteract one of the foulest consequences of bad nutrition

Specific Ocular Beta Blockers

Timolol is a nonselective beta-adrenergic antagonist. It and the other OBBs lack the membrane-stabilizing property (local anesthesia) that limited the usefulness of propranolol as an IOP-lowering medication. Timolol was demonstrated to have greater efficacy at lowering IOP than either pilocarpine or epinephrine.100,101 Ti-molol maleate has been demonstrated to lower IOP in normal, ocular hypertensive, and glaucomatous eyes.102-104 There is no clearly defined dose-response effect for reduction of IOP by timolol with concentrations ranging from 0.1 to 1.5 . A single-dose, incomplete block design study of 20 patients showed almost equivalent peak IOP reduction (no significant difference) with timolol 0.1 to 1.5 compared with fellow eyes receiving placebo or no drug. All subject received timolol at varying doses, or placebo in the study eye. The study had a somewhat complex design but is the best reported among the dose-ranging studies. There were significant IOP reductions for 24 hours...

Unexpressed ChromatophoreB Expressed Chromatophore

It scans the surrounding environment with telescopic vision that enables it to plan and execute a defense (usually concealment or flight) well in advance of the predator's approach. Phenomenal eyesight also facilitates locating prey from a great distance. As chameleons target prey, two separate images merge into one to gauge distance. Then chameleons engage their most fascinating feature the tongue.

Conclusion and Perspectives

In this chapter, we have seen different ways of computer assistance to the diagnosis of diabetic retinopathy, which is a very frequent and severe eye-disease image enhancement, mass screening, and monitoring. Different algorithms within this framework have been presented and evaluated with encouraging results. However, there are still improvements to be made. The first one is to use high-resolution images. We worked on images already used in centers of ophthalmology, but it is clear that acquisition techniques also improve and that in the coming years high-resolution images will become clinical standard. Future segmentation algorithm can make use of this high resolution (e.g. there will be more features for microaneurysm detection).

Mechanism Of Action

Cholinergic drugs have been used in glaucoma therapy for more than a century.3 They have a minimal effect on aqueous humor formation and episcleral venous pressure.1 Rather, their effect on IOP is the result of various actions on aqueous humor outflow, which have been thought consequent to agonist-induced, musca-rinic receptor-mediated contraction of the ciliary muscle.

Contraindications

Architecture of cribriform region and ciliary muscle tendon attachments in humans and higher monkeys. One type of tendon connects the anterior muscle tips to the scleral spur. A second type of tendon traverses the entire meshwork to insert into the corneal stroma. A third tendon type fans out in brushlike endings within the mesh and, via an elastic network and connecting fibrils, attaches to the juxtacanalicular and innerwall region. Redrawn with permission from Rohen JW. The evolution of the primate eye in relation to the problem of glaucoma. In Lutjen-Drecoll E, ed. Basic Aspects of Glaucoma Research. Stuttgart Schattauer Verlag 1982 3-33. Figure 5.3. Architecture of cribriform region and ciliary muscle tendon attachments in humans and higher monkeys. One type of tendon connects the anterior muscle tips to the scleral spur. A second type of tendon traverses the entire meshwork to insert into the corneal stroma. A third tendon type fans out in brushlike endings within the...

Indications And Treatment

Pilocarpine is used in the long-term treatment of glaucoma it is generally administered as a 0.5 to 4.0 aqueous solution four times per day. It is the standard cholinergic agent for treatment of open-angle glaucoma. During episodes of acute primary angle-closure glaucoma with pupillary block, 1 or 2 pilocarpine is administered two or three times over a 30-minute period to produce miosis once IOP has been lowered by secretory supressants and hyperosmotic agents to the point where iridial blood flow has been restored. Miosis pulls the peripheral iris away from the TM, thereby allowing aqueous humor to leave the eye. The miotic action of pilocarpine is also occasionally utilized to overcome the mydriasis produced by anticholinergics or sympathomimetics. Alternated with mydriatics, pilocarpine is employed to break adhesions between the iris and the lens. Pilocarpine has been used in the treatment of Adie's syndrome.27 Prolonged drug delivery may be accomplished through the use of polymer...

Basic processes learning and memory

That is, the monkeys no longer required a period during which they learned to choose the rewarded object through trial-and-error. Rather, their response on the first trial of a new problem (whether it was correct or incorrect) informed them which object to choose on subsequent trials. This understanding of the solution to the problem based on one experience with two novel objects was called learning set, or learning to learn by Harlow. It is a good example of cognitive flexibility. Learning set is still used to study aspects of learning and cognitive flexibility in humans and non-humans. Animals of a multitude of species are capable of learning set, including cats, rats, squirrels, minks, sea lions, and several species of monkeys. The investigation of learning set in rats demonstrates the importance of considering the species-typical sensory capacities of an animal when studying cognition. Rats, who have very poor vision but excellent olfactory ability, have some difficulty...

Signs and symptoms

Any visual impairment occurring peracutely or acutely, such as blurred vision or floaters - especially unilaterally - should prompt immediate ophthalmological examination of the patient. Today, not tomorrow Symptomatic CMV retinitis is an emergency - once there is a black spot in the visual field, it will be permanent. All CMV treatment regimens can only prevent progression of lesions, not reverse them.

Vitamin A Deficiency and Increased Mortality in Children Lessons From Denmark

From 1909 to 1920, the Danish ophthalmologist Olaf Blegvad (1888-1961) documented cases of xerophthalmia, or clinical vitamin A deficiency, among children in Denmark (48). From 1911 to 1917, there was a strong, gradual increase in the number of cases of keratomalacia, the most severe eye lesion of vitamin A deficiency, followed by a decline in 1918 and 1919 and then an increase in 1920. During the same period in neighboring Sweden, there was no epidemic of xerophthalmia. Blegvad showed that the export of butter and cheese from Denmark and increased consumption of margarine within the country were linked with the increase in vitamin A deficiency. The manufacture of margarine ceased in 1917 after a German submarine blockade halted importation of raw materials, and butter, which was produced in Denmark at an expensive price, was then rationed at a more affordable cost for the poor after December 21, 1917. On May 1, 1919, butter rationing ceased (Fig. 1) (48). The mortality rate observed...

Carbonic Anhydrase Inhibitors

For more than 50 years, carbonic anhydrase inhibitors (CAIs) have remained consistent and critical components in the armamentarium of the clinician. Despite systemic toxicity observed in some glaucoma patients, this category of medication has emerged as an important option for those patients who remain resistant to alternative intervention. Although beyond the reach of those individuals who have demonstrated a legitimate allergy to sulfa drugs in the past, CAIs have exhibited versatility in use across a broad range of ages and coexistent systemic comorbidities. It is the only category that can be administered as either a topical or a systemic agent, and patients rarely present with complaints of ocular hyper-emia, shortness of breath, fatigue, or loss of libido when the topical agents are administered. This chapter provides an updated evidence-based review of the efficacy and safety of CAIs in an effort to provide the clinician a suitable guide for determining when best to use CAIs...

What Have We Learned So Far from Aging Place Cell Research

One possibility that must always be considered with aged rats is that the aged memory-impaired rats fail to use the visual landmarks in the water maze and place cell recordings because their vision is poor. The example in Figure 37.2, cell A2, illustrates why poor vision appears unlikely to account for the rigidity in the place cells in this experiment. The field was rigid during the first exposure to the square arena (Sq 1), but during the second exposure the field rotated with the landmarks (Sq 2). This indicates that the visual information could at least reach the hippocampus, but on some occasions it was not encoded properly.

Breaking the News The Role of the Physician

Ianet and Marc thought their life was as close to perfection as any family's life could be. Married for 8 years, they had one daughter, Missy, age 5, and Brian, age 3 months, their long-awaited son. At Brian's 3-month routine well-baby checkup, the pediatrician remarked that Brian might have strabismus because his eyes appeared to turn in and weren't working together, as Janet later described it. The pediatrician was very reassuring, however, and told Marc and Janet that he would like the baby to be examined by a pediatric ophthalmologist just to be on the safe side. Marc had recently started a new and more responsible job so it was decided that Janet would take Brian for the eye examination herself, to minimize the amount of time Marc was away from the office. Thursday, July 14, began like many others for Janet. She got Missy off to kindergarten, kissed Marc goodbye, and packed up for the day's outing, an eye doctor's appointment. Preparing a 3-month-old to meet a new doctor was a...

Cerebral Vein Thrombosis

Patients with cerebral vein thrombosis can present with one of two major patterns. The first is with focal neurologic defects due to venous thrombosis resulting in localized infarction. Infarctions are often hemorrhagic due to continued arterial blood flow, which pumps blood into the infarcted area. Patients with deep cerebral vein thrombosis may present with severe deficits and coma due to infarction of deep brain structures. Secondly and more commonly, patients with cerebral vein thrombosis will present first with signs of increased intracranial pressure due to obstruction of venous flow and cerebral spinal fluid reabsorption. Patients will have severe headaches, nausea and vomiting and then may progress to coma. Patients may also have reduced vision and blindness due to pressure on the optic nerve. Frequently patients have a prolonged course lasting for days with gradual worsening of symptoms.

Clinical Bbbd Technique

The care of patients treated with BBBD requires a multi-disciplinary team approach. The team includes a neuro-oncologist, neurosurgeon, neuroradiologist, anesthesiologist, pharmacist, nurse coordinator, neuro-psychologist, ophthalmologist, audiologist, physical therapist, and social worker. BBBD treatment is done on two consecutive days every four weeks for up to one year. Patients undergo baseline neuropsychologic evaluation, electrocardiogram, and port-a-cath placement. At baseline and prior to each monthly BBBD treatment patients undergo neurologic and KPS evaluation, brain MRI, chest X-ray, complete blood count, chemistry panel, and urinalysis. Patients are required to have adequate hematologic, renal, and hepatic function, and must have adequate pulmonary and cardiac function to tolerate general anesthesia. Ophthalmologic assessment is done if clinically indicated. Patients treated with carboplatin in conjunction with BBBD undergo monthly audiologic assessment.

Fixed Combination Drugs

Initial therapy for glaucoma typically consists of topical medications that lower intraocular pressure (IOP), and frequently more than one agent is required to achieve adequate control of IOP. For example, initial monotherapy failed to control IOP within the first 2 years of treatment in up to 50 of glaucoma patients in the United States.1 The recent Ocular Hypertension Treatment Study randomized patients to observation or treatment in which the therapeutic goal was a relatively modest 20 IOP reduction in that study, 40 of patients randomized to treatment required more than one medication to achieve the therapeutic goal.2 The importance of making therapy convenient for glaucoma patients cannot be overemphasized. Consider the burdens of treatment from the patient's perspective Early and even moderate glaucoma is often symptom-free, which tends to reduce adherence to medical regimens. Unlike chronic therapy for some medical ailments where a clear therapeutic benefit is evident to...

Trisomy Syndromes Trisomy

Trisomy of chromosome 8 only occurs in a mosaic form in live births. Many organ systems may be involved in the disorder. The facial features are characteristic with a prominent forehead, broad-based nose, everted upper lip, high-arched and or cleft palate, stretched lingual frenulum, micrognathia, and large, dys-plastic ears with a prominent antihelix. The neck is short and broad the trunk of the body tends to be long and thin. Skeletal anomalies include structural and numerical vertebral abnormalities, spina bifida, scoliosis, pectus carinatum, absent patellae, and hip abnormalities. Renal and ureteral anomalies and cardiac defects are common. Ophthalmic features include hypertelorism, downward slanting of the palpebral fissures, strabismus, blepharoptosis, blepharophimosis, corneal opacities, cataracts, heterochromia of the irides, and colobmatous microph-

The Longevans Hooded

As mentioned above, we have chosen male Long-Evans rats for our cognitive aging research. This strain has good visual acuity even at advanced ages and is out-bred, such that genetic variability is consistently introduced into the population. Thus their general physical health and eyesight tend to be excellent well into old age, and we find very few pituitary tumors (< 5 ) in these animals upon sacrifice. Our animals are obtained as retired breeders from Charles River Laboratories, Inc., Cambridge, MA at approximately 10-12 months of age and are individually housed for another 12 months before behavioral testing. During this time, water and food intake assessments and frequent screenings for pathogens are conducted to constantly monitor their health. Extreme measures are taken to maintain a healthy and pathogen-free colony for our Long-Evans rat model of cognitive aging. Individual differences in cognitive decline described in detail below are routinely observed in this model in rats...

The Myotonic Dystrophies an Overview

Myotonic dystrophy (dystrophia myotonica, DM) is a dominantly inherited neuromuscular disease that is characterized by a distinctive combination of clinical features, including skeletal muscle myotonia and weakness wasting, cardiac muscle arrhythmias and conduction defects, unusual ocular cataracts, insulin insensitivity, male hypogonadism, balding and hypogammaglobulinemia (Harper 2001). Moreover, the genetic basis of DM is novel because this disease is caused by the expansion of different, but structurally similar, microsatellite repeats in two unrelated genes. Type 1 DM (DM1) is associated with the expansion of a d(CTG) repeat poly r(CUG) positioned in the 3'-untranslated region (UTR) of the DMPK gene, while type 2 disease (DM2) results from a d(CCTG) expansion poly r(CCUG) in the first intron of ZNF9 (Brook et al. 1992 Liquori et al. 2001). Congenital DM (CDM), which is the most severe form of this disease, is exclusively associated with very large d(CTG) expansions in the DMPK...

Modern Fixed Combinations Approved Outside The United States

The fixed combination timolol maleate 0.5 -latanoprost 0.005 (Xalacom Pfizer, Inc., New York, N.Y.) was the first beta blocker-prostaglandin combination released in 2001 after gaining regulatory approval in many regions of the world. Latanoprost was the first approved prostaglandin (in 1996) and quickly became a first-line agent of choice in the United States and around the world. Because timolol remains a popular and effective choice for adjunctive therapy, development of a fixed combination of these two agents once again reflects common clinical use. This fixed combination is approved in several countries for the reduction of IOP in patients with open-angle glaucoma and ocular hypertension. Figure 7-2. Latanoprost-timolol fixed combination versus components after timolol run-in. Adapted from Bucci MG. Intraocular pressure-lowering effects of latano-prost monotherapy versus latanoprost or pilocarpine in combination with timolol a randomized, observer-masked...

Ophthalmic Administration

Polymers such as methylcellulose, hydroxypropyl methylcellulose, and polyvinyl alcohol decrease the surface tension and increase the viscosity of solutions, thus enhancing bioavail-ability. Soft contact lenses soaked in pilocarpine have also been used. Biodegradable polymers have been employed for the controlled delivery of hydrocortisone and tetracycline.

Feeding Ecology And Diet

Eats primarily insects, but also eats spiders the same size or smaller. It avoids ants. Reported to feed on mosquitoes with lengths almost twice its own. Active hunter, able to catch larger prey primarily because of its excellent eyesight during day (especially in direct sunlight) and excellent ability to jump from a stationary position. Slowly stalks potential prey by creeping very close, usually to within 2.8-5.9 in (7-15 cm). When at reachable distance, it attaches silky thread to substrate, and then jumps on prey and paralyzing it with its venomous jaws. Powerful chelicerae are then used for chewing up prey prior to sucking up liquid contents. Does not make webs for catching prey.

Afferent Pupillary Defect Marcus Gunn Pupil

Marcus Gunn Pupil

In Low-Vision Infant. maintained and, with near fixation, accommodative miosis makes interpretation difficult. In such circumstances, normal room illumination can be used to assess optic nerve function10 (Fig. 2-3 demonstrates this technique). This approach is especially helpful in the infant or toddler who invariably fixates on the light source, making traditional testing impossible. An afferent pupillary defect can even be detected if one of the pupils is non-reactive secondary to trauma, pharmacological dilation, or ocular inflammation (Fig. 2-3). In such cases, the direct and consensual responses of the single reactive pupil must be compared. If the consensual response is less than the direct response there is an abnormality in that eye. The afferent pupillary defect is a sensitive indicator of optic nerve dysfunction and, more specifically, visual field loss.17 Retinal disease or amblyopia can also cause an afferent pupillary defect, but the disease process is usually severe and...

Deletion 4p Wolf Hirschhorn Syndrome

The physical findings in partial deletion of the short arm of chromosome 4 (see Fig. 3-3) include microcephaly, seizures, prominent glabella, midline scalp defects, preauricular dimple, cleft lip palate or high arched palate, deformed nose, hemangiomas, hydrocephalus, and undescended testes and hypospadias in males.393 Colobomatous microphthalmia is common as is hyper-telorism, epicanthus, and downward slanting of the palpebral fissures and strabismus blepharoptosis, corneal opacities (Peters' anomaly), the anterior segment abnormalities of Rieger's anomaly, and cataracts may occur.185,218,382

Drugs For Systemic Hypertension

Used for stage 2 hypertension or other compelling indications.1 Systemic hypertension and glaucoma often coexist in patients, and glaucoma patients frequently use systemic cardiovascular medications.2 Beta-adrenergic blocking drugs for long-term therapy of systemic hypertension are listed in table 9.1. In 1967, Phillips et al.3 reported that propranolol reduced IOP in seven patients with glaucoma following administration of 10 mg intravenously or 5 to 40 mg by mouth. Cote and Drance4 in 1968 described the ocular hypotensive effect of 20 to 50mg day of orally administered propranolol in 26 patients with open-angle glaucoma. Topical administration of propranolol also reduced IOP 5,6 however, membrane-stabilizing activity caused significant corneal anesthesia,6 which prevented topical use of this drug. The subsequent search for beta blockers without adverse effects led to the development of topically administered timolol.7

General Clinical Considerations

Any child exhibiting an ocular motor nerve palsy accompanied by other neurological signs deserves a consultation with a neurologist and a thorough, timely workup. It is incumbent upon the ophthalmologist to detect and treat any amblyopia that may occur. Also, prevention of amblyopia, by alternate patching, for example, can be considered in severely amblyogenic conditions such as third nerve palsies.

Low Illumination Acuity Testing

Neonate Optokinetic Nystagmus

Testing visual acuity under reduced illumination can be used to distinguish amblyopia (strabismic or anisometropic) from retinal or optic nerve dysfunction.14 If the illumination to a normal eye is decreased using a neutral density filter (no. 96 2-Log filter Kodak), the vision will be mildly reduced from 20 20 to 20 40. In an eye with a retinal or optic nerve lesion, the vision will be reduced dramatically (20 40 to 20 200) whereas an eye with amblyopia will exhibit little or no reduction (20 40 to 20 50). (Neutral-density filters can be obtained in most camera shops.) Newer electrophysiological methods of assessing Very young children (1-3 months of age) will exhibit marked lid retraction when the lights are suddenly turned off (Fig. 2-2). This primitive reflex can be used to assess function in the apparently blind infant. If little or no visual function is present, this reflex will not occur. However, if visual acuity is 20 400 or better, marked lid retraction will occur...

Preventing Diabetic Complications

As quercetin has been shown to inhibit aldose reductase, the first enzyme in the polyol pathway, a theoretical basis exists for its use in the prevention of long-term diabetic complications such as cataracts, nephropathy, retinopathy and neuropathy (Chaudhry et al 1983). Quercetin may also provide beneficial effects in people with diabetes by decreasing oxidative stress and preserving pancreatic beta-cell integrity (Coskun et al 2005).

Initial Medical Treatment

Although options for the initial management of most forms of open-angle glaucoma include laser and incisional surgery, medical therapy is typically initiated first. There are currently many medications from which to choose. Fortunately, results from several recent, randomized clinical trials are now available to provide evidence-based guidance to ophthalmologists. Glaucoma is the leading cause of irreversible blindness worldwide.1 In the past, glaucoma was primarily defined by elevated intraocular pressure (IOP). Although elevated IOP is recognized as a significant risk factor for glaucoma, it is not the only one. Of patients with open-angle glaucoma, 17 never exhibit IOP greater than normal.2 In some populations, including Hispanics of Mexican descent and the Japanese, fewer than 20 of those with glaucoma initially have elevated IOP.3,4 Primary open-angle glaucoma (POAG) is now defined by the American Academy of Ophthalmology (AAO) as a progressive, chronic optic neuropathy where IOP...

To Treat Or Not To Treat

Data from these clinical trials are very helpful in broadly guiding our treatment plans however, glaucoma treatment must be individualized. After evaluating all available information for a given patient, a decision must first be made whether treatment is necessary. In certain rare circumstances, patients' life expectancies may be limited, and their visual loss from glaucoma may not be very advanced. In this situation, a determination must be made regarding the likelihood that these patients will become visually handicapped from glaucoma without treatment. If they are considered to be at low risk, treatment may not be required. Clinicians must be very careful in pursuing this course, because it is notoriously difficult to predict the life expectancy of individual patients. Also, with the relatively low side effect profile of newer glaucoma medications and SLT, a conservative, safe, and effective treatment protocol can be instituted in most cases.

Initial Treatment Modality

After setting a target IOP, the ophthalmologist must decide how to reach it. As discussed above, there is support for initial medical, laser, and surgical interven-tion.20,21,23,41 Therefore, before selecting one of these treatment protocols, it is imperative to have a frank discussion with patients about the status of their disease and all treatment options. Only after all the options have been reviewed and patients' questions answered can patients properly give informed consent to the treatment regimen. If more invasive treatments are not chosen initially, patients will be aware of possible future options. The negative effect of prior long-term medical therapy on the success of filtration surgery is important to consider. With newer medications, maximum medical therapy may be achieved with as few as three medications. The most common approach is to begin with medical treatment. Glaucoma is a slowly progressive disease. Therefore, obtaining a baseline set of data prior to performing...

Initial Medical Management

Once a decision has been made to pursue medical therapy, the ophthalmologist must choose among the many medical options available. Prior to selecting a medication, the physician should review the patient's medical history, allergies, and experience with previous glaucoma medications. Documenting efficacy and side effects of medications previously used in a dedicated location in the medical record will reduce the likelihood of repeating unsuccessful therapeutic trials in the future. Ocular conditions can also affect the choice of medications. Uveitis and cystoid macular edema (CME) are infrequently associated with prostaglandin analogs.51-55 Although rarely used, dipivefrin and epinephrine are associated with CME in aphakic patients. Echothiophate iodide is not used in phakic patients because of its cataractogenic properties, but it is a very effective treatment in pseudophakic and aphakic individuals. Miosis from any cholinergic agent can decrease visual function in patients with...

Additivity Of Medications

Table 11.1 General Guidelines for Combination Therapy for Glaucoma In view of the apparent additive IOP-lowering effect of beta blockers to the PA class of glaucoma medications, newer drop formulations containing both medications in one bottle are currently being studied.15-17 Published data indicate that fixed combinations of a PA and a beta blocker appear to provide near-equal IOP-lowering effects compared to concomitant use of the two drugs while providing the benefit of decreasing dosing frequency, reducing preservative exposure, and possibly improving compliance. These medications may prove advantageous in treating patients while offering the added benefit of saving on cost of medications (depending on drug pricing). A monocular therapeutic trial of 3 or 4 weeks can determine if a drug is effective however, beta blockers and brimonidine can have significant crossover activity (you may see IOP lowering in the eye not being treated). An in-office monocular therapeutic trial can be...

Special Considerations For Aging Colonies

Aging results in the progressive decline of the cardiovascular system, characterized in part by an increase in wall thickness of the ventricles. Aged rodents experience ventricular hypertrophy associated with an excess accumulation of collagen.47 Systemic mitochondrial dysfunction will frequently compromise muscle and cardiac function. Therefore, it is useful to evaluate mitochondrial physiology and cardiac function. Many neurological deficits associated with aging are subtle and not grossly observable, especially learning and memory deficits. The Morris water task is presently the most frequently used paradigm to evaluate learning and memory abilities in genetically engineered mice.22 Aged C57BL 6 mice show impairments in performance on this task.48 Additional neurological assessments for locomotor function include open field activity and rotarod procedures.49 Hearing is another neurosensory mechanism that exhibits an age-associated decline. The auditory-evoked brainstem response...

Improvement Of Compliance

The relatively recent introduction of topical CAIs, PAs, and alpha agonists has made life easier for our glaucoma patients compared to those treated just 10 to 15 years ago. Maximal medical therapy is now a combination of the nonselective beta blocker timolol and topical CAI dorzolamide morning and night, a PA at night, and an alpha agonist twice a day, for a total of five drops in each eye over the course of Even the most conscientious patient can forget when to take particular drops. In addition, most pharmacies print prescription instructions in small type that is often difficult for some glaucoma patients to read clearly. This has improved recently, with many pharmacies providing larger type when requested, but this is by no means universal. We have found that the use of a medication card along with specific verbal instruction enhances compliance. A recent study by Kharod et al.18 verified that written instructions improved patients' knowledge of their prescribed regimens. If the...

Visual Pathway Symptoms

Optic neuritis is one of the most common manifestations of MS, occurring in 14 to 23 of cases (36-39). Patients usually complain of dimming of vision unilaterally, generally accompanied by photophobia and pain aggravated by eye movement. Examination reveals diminished visual acuity of varying severity, and detailed visual field evaluation frequently shows a central scotoma (84). Visual loss is seldom total, and good recovery of vision usually occurs within six months, even when the initial visual loss is extremely severe (85,86). Fundoscopy may Even in the absence of acute optic neuritis, many patients demonstrate clinical abnormalities of optic neuropathy. This may be manifest by diminished visual acuity, impairment of color vision as detected with Ishihara plates (87), abnormal visual field examination, or a positive swinging flashlight test'' (88) indicative of an afferent pupillary defect (Marcus Gunn pupil). Subtle abnormalities of vision may also be detected by the use of...

Enhancement Of Surveillance

Once patients are receiving maximal tolerated medical therapy for their glaucoma, they should be seen more frequently. A patient with a stable optic nerve head, IOP, and visual fields may be seen every 4 to 6 months. Patients are usually placed on maximal medical therapy, however, due to evidence of more progressive or unstable disease. As a result, examinations ranging from every 2 to 4 months may be in order. These exams should document not only IOP but also the optic nerve head for any changes, even if through an undilated pupil. If progressive changes in the cup or nerve fiber layer are evident, as revealed by physical examination and perhaps structural imaging, then repeat visual field testing is appropriate. In today's environment of managed care, it is important to remember that insurance companies should not determine when a patient with progressive glaucomatous changes should have functional testing however, the financial consequence of unreimbursible diagnostic evaluation...

When Medical Therapy Fails

A surgical procedure is indicated when medical therapy no longer adequately controls IOP. While some feel surgery should be the initial treatment for glaucoma, most clinicians in the United States use LTP, either with an argon laser (argon LTP ALT ) or a frequency-doubled Q-switched Nd YAG (neodymium-doped yttrium aluminum garnet) laser (selective LTP SLT ), and trabeculectomy when medical therapy fails. Although the Glaucoma Laser Trial has shown at least equal efficacy for initial medical therapy and for initial ALT, ALT causes a permanent anatomic alteration of the body and has potential significant adverse effects.22 Although the likelihood of such serious ALT side effects is small, most clinicians in the United States favor reserving ALT until after medical therapy has failed. An even stronger statement can be made for withholding filtering surgery until after the failure of medical therapy and ALT. Filtration surgery is at least as effective at IOP reduction Which procedure to...

Clinical Assessment

Variable diplopia or ptosis most often prompt an ophthalmologic evaluation. Patients with these symptoms are evaluated for signs and symptoms of generalized myasthenia such as facial weakness, dysphonia, arm or leg weakness, chewing weakness, and respiratory difficulties. In ocular myasthenia, however,

Special Therapeutic Situations

Certain discrete glaucomas and difficult clinical problems require the use of multiple medications or require medications to be used in conjunction with laser treatment or filtration surgery. The specific medications used may differ from those used in primary open-angle glaucoma. Directed therapy, when applicable, should be a strong consideration in treatment. Directed therapy is conceptually simple. It merely means devising specific treatments for specific diseases. This fundamental tenet of medicine has been applied infrequently in the treatment of glaucoma. The simplification of glaucoma into congenital, open-angle, and angle-closure glaucoma has led us to focus on glaucoma as the disease and intraocular pressure (IOP) as its treatable aspect. Specific glaucomas, however, lead to trabecular dysfunction by specific series of events. In theory, intervention could be applied at each of these steps. Little emphasis has been placed on preventive treatment or disease-specific therapy,...

Determinism Versus Volition

The issues surrounding the free-will determinism debate as they apply to the notion of addiction and drug use are fully discussed in Davies (1996, 1998). It is sufficient to say that choice of a paradigm within which to study humankind is exactly that a choice. The wish to conceptualise people in a certain way in order to study them is not an act of science based on empirical observation and inductive reasoning a la Popper (Popper, 1959) but a choice based on what you wish to achieve and how you wish to frame your questions. Determinism is not truth. An excellent book by Fernandez-Armesto (1997) outlines the different species of knowledge espoused by different societies and exposes the myopia behind the view that the Western empirical view of knowledge represents some absolute 'truth'.

Other Special Situations

Initial surgical treatment should not be delayed in an attempt to achieve medical control of IOP in infants with congenital glaucoma. Medications are primarily used preoperatively to allow corneal edema to clear, improving visualization at the time of examination under anesthesia and surgery, and to help control any damage that might occur in the interim preoperatively (see also Chapter 13). If trabeculotomies and or goniotomies fail and trabeculectomy is believed to be required, some surgeons would attempt medical control at this point. Miotics can induce visually disabling myopia in the young patient and are not recommended for infants. Older children are better able to tolerate topical medications. Again, parents should be carefully apprised of potential side effects of any glaucoma agents being used. If psychological or behavioral difficulties arise, a trial of discontinuing successive potentially causative medications should be undertaken. 12.4.2...

Types Of Agerelated Visual Diseases And Their Impact On Society

The predominant causes of age-related visual impairment and blindness vary between the developed and developing countries, and even within various demographic and ethnic groups within single countries (Thylefors et al., 1995). There are many causes of visual loss in elderly patients, including diabetic retinopathy, stroke, and retinal vascular occlusive disease, along with other age-related visual diseases including pterygia and presbyopia. However, in most populations the greatest causes of blindness and vision loss in the elderly include cataracts, glaucoma, and age-related macular degeneration (Congdon, Friedman, and Lietman, 2003 Buch et al., 2004). Cataracts are the leading cause of blindness across the world, blinding 17 million persons worldwide. Cataracts are usually correctable by surgery in developed countries, with about 5 of the American population over 40 years old having undergone cataract surgery. However, they remain a significant cause of visual disability even in...

Clinical Features and Natural History

Source Modified from Glaser JS, Bachynski BN. Intranuclear disorders of eye movement. In Glaser JS (ed) Neuro-ophthalmology, 2nd edn. Philadelphia Lippincott, 1990 402, with permission.166 Source Modified from Glaser JS, Bachynski BN. Intranuclear disorders of eye movement. In Glaser JS (ed) Neuro-ophthalmology, 2nd edn. Philadelphia Lippincott, 1990 402, with permission.166 Affected fundi demonstrate a diffuse pigmentary retinopa-thy that characteristically involves the posterior pole as well as the periphery and generally consists of a salt-and-pepper pattern of pigment clumping. Commonly both rod and cone function are reduced on electroretinography,341 and although it has been noted that only 40 of patients have decreased visual acuity or night blindness,54 photoreceptor function can diminish insidiously with time.

Pregnancy and Pediatric Patients

Glaucoma in younger individuals is less common and is managed differently compared with adults. In young adults, pregnancy and lactation can be considerations in medical management decisions. Pediatric glaucoma is treated primarily surgically, and medications are usually in a supportive role, often to bridge the gap to surgery and clear the cornea prior to surgery. Although long-term response to medical therapy can be achieved in children, glaucoma medications are often used as adjunctive therapy after surgical treatments. The effectiveness and side effect profiles for some medications are significantly different in very young patients, which can influence management decisions. In this chapter, we review glaucoma medical therapy considerations in pregnancy, lactation, and pediatric patients.

On the Accuracy of Quantitative Measurements in Image Intensifier Systems

Image-intensifier tubes, built with electron focusing lenses, may have five aberrations distortion of image caused by the input phosphor screen, astigmatism, curvature of image field, spherical aberration, or coma. Aberration caused by the curvature of an input phosphor surface changes the shape of images more than any other type of distortion. The discrepancy in size may reach even 20 in the periphery. Thus, the accuracy of measurement of abnormalities depends on its location within the image. Pathology viewed in the image periphery appears wider than that viewed in the central part of the image.

Compliance with Ocular Medication

One of the most difficult challenges in treating glaucoma is ensuring patient compliance with medication. Compliance can be defined as taking a therapeutic regimen prescribed by a physician. Compliance is more than simply following the doctor's orders.'' It requires an active role on the part of the patient to schedule and attend office appointments, fill prescriptions, and take medicines as prescribed. Implied in the concept of compliance is the understanding that the patient will report any medication side effects or other concerns to the physician without independently altering the regimen. It is important to define three other terms related to medical therapy defaulting, persistence, and adherence. Defaulting is defined as failure to comply, that is, not following a therapeutic regimen. Persistence is a measure of time that the patient is taking a medication the time between starting and discontinuing a particular drug. Adherence is a measure of doses taken, that is, the extent to...

Risk Factor Surveillance and Medical Room Utilization

Room was limited to simple manual tallies. Because these encounters were documented on a paper record, there was no ready way to generate reports by type of complaint or diagnosis, view other data about students during a consultation (such as attendance, vision screening, immunization records), or track students over time, especially if the student moved within the school system, a relatively common occurrence. To address this, an ambitious effort was undertaken to automate the school health record. The Automated School Health Record (ASHR) also produces reports, so that the nurse can generate, for example, a list of all children who failed the vision exam, or have asthma or diabetes.

Prevalence Of Noncompliance

It is difficult to estimate what percentage of patients with glaucoma fail to take their medications as prescribed, primarily because we lack a foolproof method of detecting noncompliance. Published studies report noncompliance rates of 28 to 59 among glaucoma patients.2-7'13-15 The large range can be attributed to differences in the definitions of compliance used and in the measurement techniques employed. Rather than classifying patients as either compliant or noncompliant using an arbitrary criterion, it may be more informative to measure the level of compliance (adherence). One study used an electronic monitor to measure compliance to a treatment regimen of pilocarpine taken four times daily.10 Monitor data indicated that patients administered a mean standard deviation of 76 24.3 of prescribed doses. The same patients reported taking a mean standard deviation of 97.1 5.9 of their doses. These data indicate that noncompliance is common and support the belief that patients who admit...

Scope Of Ethical Issues Addressed In This Chapter

G, a 79-year-old widowed, white woman, has been admitted to the short-stay unit of a comprehensive geriatric health care center after discharge from the hospital for hip replacement. She has been discharged to the short-stay unit as part of a contract arrangement between the hospital and the geriatric health care center. Her care plan includes postsurgical follow-up, physical therapy, and planning for the future. Her medical problems include mild heart failure and moderate visual impairment, secondary to macular degeneration. She also has moderate right-side hearing loss. Her poor eyesight contributed to the fall that resulted in her broken hip. This fall occurred at home, where Mrs. G lives alone. She has lived in this home for 50 years and alone in this home since her husband died 10 years ago. She has three children, her oldest, a son, and two daughters, all of whom are married with children of their own. She is closest to her youngest child, who is 49 and has three teenage...

Myotonic dystrophy dystrophia myotonica

Myotonic dystrophy is an inherited autosomal dominant condition. There is muscular weakness and wasting which can produce a rather 'drooping expression'. Myotonia may be present, which may be apparent due to the delay in the patient releasing his her grip upon shaking hands. It can be demonstrated by a delay in opening and closing fists repetitively or by difficulty in opening eyes after tight closure. The other features include frontal balding, ptosis, cataracts and cardiac conduction defects.

Clinical Considerations

In patients with diabetes, retinal blood vessels frequently become leaky and exude fluid into the retina (particularly in the macula), leading to loss of visual acuity. It is the leading cause of blindness in the developed world and may be reduced by strict regulation of blood glucose levels.

Detection Of Noncompliance

There is no gold-standard technique for detecting poor compliance thus, in the day-to-day office practice of glaucoma, detection of noncompliance is exceedingly difficult. Methods used to detect noncompliance in clinical studies, such as electronic medication monitors, pill counts, and blood tests for drug or metabolite levels,10,13,55-57 are expensive and may not be applicable to ophthalmic medications. Physicians are usually unable to accurately gauge the level of compliance in their own patients, even those who have been under their care for years.3,10,55,58 The value of asking a patient about compliance is relatively low because most patients will tell their doctor ''what the doctor wants to hear'' instead of accurately reporting their adherence.3,7,10,15,56,57,59-61 If a patient admits to poor compliance, he or she is likely to be telling the truth. Questionnaires have been developed to determine compliance with medical regimens.62 It is possible that these will be useful in...

Strategies To Improve Compliance

As described above, compliance diminishes as the frequency and complexity of dosing increases. One of the most effective approaches a physician can have toward glaucoma therapy is to keep the regimen as simple as possible. One way is to prescribe daily dosing of medications instead of twice daily when possible. Using the lowest number of medications to achieve the desired therapeutic effect is also helpful, and this is aided by combination eye drops such as 1. Explain glaucoma and rationale for treatment. 1. Reemphasize information about glaucoma on return visits. 14.5.3 Patient Education. Too frequently, physicians assume that, because they have explained the disease process of glaucoma at the initial diagnosis, the patients will retain the information. In fact, most patients do not recall instructions given during any one outpatient visit68 and may be especially prone to forget instructions given at an initial visit because of nervousness, shock at...

Agerelated Macular Degeneration

A 2002 Cochrane review assessed the effects of antioxidant vitamin and or mineral supplementation on the progression of ARMD and found that evidence of effectiveness is currently dominated by one large trial that showed modest benefit in people with moderate to severe signs of the disease who were administered antioxidant vitamins and zinc together (Evans 2002). More recently, results of the Age-Related Eye Disease Study were published (AREDS 2001 ), which showed that high-dose vitamins C and E, beta-carotene, and zinc supplementation delayed the progression from intermediate to advanced disease by 25 over 5 years. The 11 centre, doubleblind, prospective study involved 3640 volunteers aged between 55 and 80 years who were randomly divided into four treatment groups, receiving either antioxidant supplements (500 mg vitamin C, 400 international units (IU) vitamin E, and 1 5 mg beta carotene daily), zinc oxide and cupric oxide (80 mg elemental zinc, 2 mg elemental copper daily),...

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