Protean Drainage Patterns of the Left Renal Vein: A Cadaveric and Retrospective Clinical Study on the Surgical Implications and Technical Feasibility.

BACKGROUND: The diverse drainage patterns of the left renal vein (LRV), often with asymptomatic congenital anomalies, present considerable challenges in renal and retroperitoneal surgical contexts. The potential for significant bleeding and subsequent renal compromise upon vascular injury highlights the need for increased surgical awareness. OBJECTIVE: This study investigates the LRV's variable anatomical drainage patterns and morphometry. It also evaluates the embryological factors contributing to these variations and discusses their surgical implications and technical considerations. METHODS: Anatomical dissections were conducted on 21 adult human cadavers within the Department of Anatomy. Concurrently, a retrospective analysis was conducted on 15 patients who underwent various retroperitoneal surgical interventions in the Urology Department. Demographic variables and intraoperative findings were recorded and analyzed. RESULTS: Dissection analysis predominantly identified preaortic LRVs in 18 cadavers. Notable anatomical variations included a circumaortic left renal vein (CLRV), a delayed preaortic confluence of extrahilar duo LRVs, and an extrahilar tetramerous confluence with a retroiliac topography. The majority of LRVs usually end in the inferior vena cava. However, an extrahilar tetramerous variant had an unusual drainage pathway. Out of 15 cases, three (20%) had a retroaortic left renal vein (RLRV). One patient with a nonfunctioning kidney had type 1 RLRV, and another patient with pelvic ureteric junction obstruction had type 4 retroiliac left renal vein (RILRV). In both of these patients, symptoms were relieved after surgery. In a young patient with left varicocele and microscopic hematuria who had type 2 RLRV, symptoms resolved spontaneously after a few months. CONCLUSION: A thorough understanding of the variable anatomical drainage patterns of the LRV is crucial for surgeons. Accurate preoperative identification can provide valuable insights, potentially leading to improved surgical outcomes in renal procedures.

Bilateral High Trifurcation of the Common Carotid Artery and Variable Emergence of the Lower Branches of the External Carotid Artery: A Cadaveric Case Report.

Trifurcation of the common carotid artery in the neck region is a rare anatomical variation. In the present study, we reported a rare case having the combination of anomalies of the bilateral high common carotid arteries trifurcation and variable origin of lower branches of the external carotid artery during routine dissection of the head and neck region of a 60-year-old male cadaver in the Department of Anatomy. Both on the left and right sides of the neck region, the common carotid artery gave off three terminal branches: internal carotid artery, external carotid artery, and ascending pharyngeal arteries. Further, we also observed the presence of bilateral linguofacial trunks (common arterial trunks) that emerged from the external carotid arteries and also the left superior thyroid artery that originated directly from the left common carotid artery. Even though the embryogenesis of the variable origin of such arterial trunks is not apparent, it is very indispensable to have sound knowledge and better comprehension of the accurate anatomical architecture of such a rare combination of carotid arterial system anomalies for correct interpretation of the vascular imaging that pave the pathway for successful execution of surgical interventions in the neck region because of its utmost clinical implication.