Eyelids

The ophthalmic surgeon's most common biopsy is the eyelid. To most intents and purposes the laboratory management is that of a biopsy of skin. However, the problem for the ophthalmologist is gaining adequate clearance for malignant lesions as a wide excision of a lid lesion may deprive the patient of sufficient lid cover for the eye resulting in a lack of lubrication and protection from abrasion and infection. To this end, marking the orientation of the specimen and the limits of excision is of great importance.

It is best practice that the surgeon draws a diagram of the area and marks the lateral or medial, superior or inferior margins of the biopsy specimen with sutures and records the marks made on the diagram. The deep limit can be marked with dye in the laboratory.

The most common tumours of the eyelid are basal cell carcinoma and squamous cell carcinoma. Other tumours to be considered are malignant melanoma, sebaceous gland tumour and Merkel cell carcinoma. In some oculo-plastic operations a series of biopsies from the margins of excision may be sent to the laboratory for frozen section and report, in order to ascertain whether or not excision of a malignant lesion is complete. This is difficult work, relying on cooperation between surgeon and the laboratory to identify correctly the orientation of the specimens.

Orbital bone (roof)

Fornix

Upper eyelid

Anterior chamber Cornea Iris

Lower eyelid

Ciliary body

Zonular ligament

Lens

Orbital bone (roof)

Fornix

Ciliary body

Zonular ligament

Lens

Upper eyelid

Anterior chamber Cornea Iris

Lower eyelid

Orbital bone (floor)

Posterior chamber (vitreous) Retina

Choroid Sclera Dura and meninges

Optic nerve

Filtration angle trabecular meshwork Fornix Schlemm's canal

Orbital bone (floor)

Upper eyelid

Upper eyelid

Iris

Figure 20.1. Anatomy of the eye.

Iris

Figure 20.1. Anatomy of the eye.

The gamut of benign tumours include: squamous papillomas, keratoses, naevi, inclusion cysts, chalazion and molluscum contagiosum.

The eyelid biopsy is often a wedge resection of the lid. A central section through the eyelid to ascertain the deep limit of excision and a superior or inferior limit of excision are taken. The lateral blocks are cut through from the lateral or medial aspect towards the centre. This allows all six limits of excision to be judged (Figure 20.2).

0 0

Post a comment