Radiologic anatomy of the right adrenal vein: preliminary experience with MDCT.

OBJECTIVE. The purpose of our study was to determine how frequently the right adrenal vein could be unequivocally identified on MDCT and the spectrum of anatomic variations seen in the right adrenal vein. MATERIALS AND METHODS. Contrast-enhanced MDCT was performed in 104 patients with thoracoabdominal vascular disease using an 8-MDCT scanner. Both axial and multiplanar images were reviewed by two radiologists. The following points regarding the right adrenal vein were evaluated: degree of visualization; relationship to accessory hepatic or other veins; anatomy, including location of the orifice in relation to the surrounding structures; direction from the inferior vena cava; and length and diameter. RESULTS. The right adrenal vein was detected in 79 (76%) of 104 patients. The right adrenal vein formed a common trunk with the accessory hepatic vein in six (8%) of the 79 patients. The orifice was craniocaudally located between the level of vertebrae T11 and L1. Among the 73 patients, the right adrenal vein joined the inferior vena cava in the right posterior quadrant in 71 patients (97%) and in the left posterior quadrant in two (3%). The transverse direction from the inferior vena cava was posterior and rightward in 56 patients (77%) and posterior and leftward in 17 (23%); the vertical direction from the inferior vena cava was caudal in 65 (89%) and cranial in eight (11%) patients. The length and diameter averaged 3.8 and 1.7 mm, respectively. CONCLUSION. MDCT enabled the identification of the right adrenal vein and delineation of its anatomy, including its position and relationship to surrounding structures.