Aneurysm of the left ascending lumbar communicating vein: Its prevalence and possible association with nutcracker phenomenon

Abstract

Purpose To evaluate abdominal computed tomography (CT) studies in respect of the prevalence of the left ascending lumbar communicating vein (ALCV) and ALCV aneurysm and to identify possible causes of aneurysm development in the ALCV. Methods Contrast-enhanced abdominal CT examinations were retrospectively investigated for the prevalence of the ALCV in the adult population. In patients with ALCV, the diameters of the following vessels were measured: ALCV, left renal vein (LRV) at two levels, compression ratio of the LRV (CR), left gonadal vein, right and left ascending lumbar veins (ALVs). The aortomesenteric angle was also measured for preaortic LRVs. ALCV aneurysm was noted during the assessment. Results Evaluation was made of 500 patients. ALCV was found in 240 patients (48%), more common in patients with retroaortic LRV and circumaortic LRV than in patients with preaortic LRV (p = 0.003). The mean diameter of the ALCV was 3.85 ± 2.06 mm. ALCV and the left gonadal vein merged to form a common vein draining into the LRV in 23 patients with preaortic LRV (9.6%). Of the patients with ALCV, 19 (8%) had aneurysm. The diameter of the left ALV and CR were significantly greater in patients with aneurysm than in patients without (p = 0.001 and 0.032, respectively). Patients with ALCV aneurysm had a significantly narrower aortomesenteric angle (p = 0.004). Conclusion The results of this study indicated that a narrower aortomesenteric angle and a greater CR might play a role in the development of ALCV aneurysm.