Angiographic Techniques

Postmortem angiography is among the most important applications of roentgenologic methods in the autopsy room. For con-trastmedia, see Chapter 15. Because of its importance, postmortem coronary angiography is described here. Similar methods, applied to other organ systems, have been presented in Chapters 4-6.

POSTMORTEM CORONARY ANGIOGRAPHY Many contrast media have been used in the past (7,8) but barium sulfate with gelatin is now preferred (9,10), although iodinated dyes can also be used (11). For quantitative studies, a radioisotope dilution method has been reported (12). Double-contrast techniques and in situ angiography (Fig. 12-4) have also been described (13-15). Radiopaque dyes used clinically are applicable to the coronary arteries at autopsy (Chapter 15). A setup for controlled-pressure coronary angiography is shown in Fig. 12-5. For this procedure, the heart is removed with 2-4 cm of the major vessels attached. Postmortem clots are removed by irrigation with saline. Cannulas of suitable size are placed into the coronary ostia. Care is taken to identify an independent ostium. Ligatures are placed around the coronary arteries and are tied as near as possible to the origins.

The cannulated heart is suspended in isotonic saline or Kaiserling I solution at about 45°C. The coronary arteries are perfused at a low pressure with isotonic saline. This is continued for several minutes, with use of100-200 mL, until the return through the coronary sinus is free of blood.

The previously prepared barium-gelatin mixture (Chapter 15) is drawn into two 30-mL syringes. These are attached, via three-way stopcocks, to the apparatus shown in Fig. 12-5, and the actual injection is begun. Care is taken to avoid introduction of air bubbles at any stage of the procedure. While the system is kept supplied with contrast medium by way of the syringes, the pressure is increased almost simultaneously to a maximum of 110 mm Hg. Lacerated vessels may require ligation at this stage, but these are rare in our experience. A control roentgeno-gram can be prepared at this time. The heart chambers may be irrigated to remove any contrast material that enters into the lumens. With the coronary cannulas still in place and maintaining a pressure of 100-120 mm Hg, the chambers are packed with formalin-soaked cotton to their approximate normal size and shape and the specimen is immersed in cold Kaiserling I or formalin solution (Chapter 14). The heart is cooled for 1-3 h to permit the gelatin to set and then roentgenograms are prepared.

Angiography may underestimate the severity of obstruction if the narrowed region is compared to an adjacent segment that is considered normal but is actually stenotic. Conversely, microscopy can overestimate the degree of narrowing if the effect

Fig. 12-2. Shielded autopsy room for roentgenologic examination. In the background is a Machlett Super Dynamax Tube and a Picker X-ray table. In adjacent room to the left, a 300-mA Keleket X-ray machine with a 125-kV generator is installed. In the foreground is a mobile autopsy table with a separate service island.

Fig. 12-2. Shielded autopsy room for roentgenologic examination. In the background is a Machlett Super Dynamax Tube and a Picker X-ray table. In adjacent room to the left, a 300-mA Keleket X-ray machine with a 125-kV generator is installed. In the foreground is a mobile autopsy table with a separate service island.

Fig. 12-3. Autopsy rack for postmortem roentgenography with transportable X-ray machines. This rack is 198 by 40 cm and consists of an aluminum frame (upper) with channels that permit the X-ray casette to slide to the desired position. The casette is inserted at the end of the rack and can be moved by hand from below (lower). The rack is covered with X-ray Bakelite, 0.64 cm thick. The Bakelite seams are watertight so that autopsies can be done on this rack and contamination of the inside can be kept to a minimum.

Fig. 12-3. Autopsy rack for postmortem roentgenography with transportable X-ray machines. This rack is 198 by 40 cm and consists of an aluminum frame (upper) with channels that permit the X-ray casette to slide to the desired position. The casette is inserted at the end of the rack and can be moved by hand from below (lower). The rack is covered with X-ray Bakelite, 0.64 cm thick. The Bakelite seams are watertight so that autopsies can be done on this rack and contamination of the inside can be kept to a minimum.

Fig. 12-4. Normal coronary angiogram in situ. The sternum was split in the midline and about 300 mL of barium sulfate-gelatin mixture was injected into the ascending aorta without pressure regulation, by hand with a large syringe. Superior portion of ascending aorta has been clamped off.

Fig. 12-5. Setup for controlled pressure injection of contrast medium into coronary arteries. In this instance, each syringe contains chromopaque of a different color and is connected to one of the coronary orifices and the pressure-regulating system. The heart is suspended in Kaiserling solution or saline in the container on the right, which is in an ice-water bath. The two independent pressure-regulating systems with manometers are on the left.

Fig. 12-5. Setup for controlled pressure injection of contrast medium into coronary arteries. In this instance, each syringe contains chromopaque of a different color and is connected to one of the coronary orifices and the pressure-regulating system. The heart is suspended in Kaiserling solution or saline in the container on the right, which is in an ice-water bath. The two independent pressure-regulating systems with manometers are on the left.

of compensatory dilatation of atherosclerotic segments is not considered (16). Thus, coronary angiography does not replace microscopy. Although arteriography localizes obstructive lesions, microscopy is still necessary to determine its nature—for example, chronic atherosclerosis vs acute plaque rupture with stenosis.

The arteries of the extremities can be studied by angiography with a pressure-controlled system (17), resembling the system used with coronary arteries. As mentioned in Chapter 3, phlebography and lymphangiography (Fig. 12-6) can also be performed at autopsy. Intraosseus phlebography can be used for

Fig. 12-6. Postmortem lymphangiography showing dilated lymphatics in the hepatoduodenal ligament and the anterior mediastinum in a patient with liver cirrhosis and congestive heart failure. The lymphatics drain in the subclavian vein as shown by the presence of contrast medium in this vessel. Adapted with permission from ref. (18).

Fig. 12-6. Postmortem lymphangiography showing dilated lymphatics in the hepatoduodenal ligament and the anterior mediastinum in a patient with liver cirrhosis and congestive heart failure. The lymphatics drain in the subclavian vein as shown by the presence of contrast medium in this vessel. Adapted with permission from ref. (18).

the evaluation of thrombosis of deep leg veins, but the method is a bit cumbersome (19).

ANGIOGRAPHY OF OTHER ORGANS Pulmonary angiography and bronchography is described in Chapter 4; the demonstration of esophageal varices and mesenteric angiography is presented in Chapter 5; in Chapter 6, cerebral arteriography, venography, and ventriculography are discussed; and in Chapter 15, the use of angiographic methods in the study of museum specimens is shown. Roentgenologic and other imaging techniques in specific clinical or forensic diseases and conditions are also shown in Part II.

Blood Pressure Health

Blood Pressure Health

Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...

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