Distended left renal vein: CT/sonographic normal variant

Area of Science:

• Vascular anatomy
• Radiology
• Urology

Background:

• The left renal vein (LRV) commonly exhibits caliber variations.
• These variations are often attributed to extrinsic compression.
• The "nutcracker" phenomenon describes LRV compression between the aorta and superior mesenteric artery (SMA).

Purpose of the Study:

• To investigate the prevalence and anatomical basis of LRV caliber variations.
• To assess the relationship between LRV caliber and the aorta, superior vena cava, and duodenum.
• To explore a potential association between a distended LRV and varicocele.

Main Methods:

• Retrospective analysis of 72 patients.
• Evaluation of imaging studies (CT and sonography) for LRV caliber.
• Correlation with anatomical structures: aorta, superior vena cava, duodenum.
• Assessment for varicocele presence.

Main Results:

• Significant caliber variations in the LRV were frequently observed.
• The compression appears related to the aorta posteriorly and the SMA anteriorly.
• The third part of the duodenum may also contribute to the compression.
• Preliminary evaluation suggested a possible link between distended LRV and varicocele.

Conclusions:

• The "nutcracker" effect is a common cause of LRV caliber variation.
• Anatomical relationships involving the aorta, SMA, and duodenum are crucial.
• Further research is warranted to confirm the association between LRV distention and varicocele.