Selective adrenal phlebography.

Abstract

Catheterization of the adrenal veins is potentially a useful clinical tool since it permits not only detailed visualization of the inner glandular vasculature but also sampling of effluent hormones. Bucht (1) , was the first investigator to study the left adrenal vein angiographically in man; since that time there have been surprisingly few subsequent articles (2, 3) on this subject. We have developed a technic for catheterizing with facility both adrenal veins in man. On the basis of three years experience, we now feel that adrenal phlebography does indeed have wide clinical application. Anatomy The intraglandular venous circulation is complex and incompletely understood (4, 5). The cortex and medulla are drained in series by sinusoids, venules, and muscular veins which join to form the central vein. This then becomes the adrenal vein as it exits on the ventral groove of the gland. It should be noted that the main venous branches are cuffed by invaginated folds of cortex and that even the central vein is surrounded by a thin layer of cortex. At the corticomedullary junction, there is a rich plexus of sinusoids which is drained independently into the medullary veins by relatively few channels. The adrenal capsular plexus is drained by the many venae comitantes, which accompany the small capsular ramifications of the adrenal arteries into renal capsular veins, lumbar veins, phrenic veins, and others. Direct intervenous anastomotic connections linking the central vein with capsular veins and their branches have also been frequently observed. Our own injection studies with oily and aqueous contrast media confirm these findings (Fig. 1). Although it is assumed that under normal conditions the major adrenal output of medullary and cortical hormones drains into the central vein, it is also reasonable to suggest that the capsular veins represent an excellent alternative pathway in times of stress or in disease. Well developed eccentric longitudinal muscle bundles characteristically present in the central vein and its larger tributaries are presumed to play a dominant role in the control and expulsion of glandular hormones. The right adrenal vein is very short and enters usually in a cephalad direction into the right posterolateral border of the inferior vena cava at the level of T12 or upper border of L1. The left adrenal vein after joining the left phrenic vein empties into the superior border of the left renal vein opposite the gonadal vein. Exceptions to this standard anatomy textbook description have recently been emphasized by Gagnon (6) and Johnstone (7). These authors found not only examples of multiple adrenal veins but also instances in which the right vein emptied into the renal or hepatic vein and the left into lumbar and renal veins and even into the portal system.