Evaluation of portal vein variations in multidetector CT

Abstract

Aim: It is important for surgeons to have a comprehensive knowledge of vascular anatomy when performing liver interventions. For example, liver transplantation requires a vast understanding of vascular anatomy and variations. This study aimed to evaluate the intrahepatic branching pattern of the portal vein to find out unknown variations. Methods: Multidetector computed tomography images of the abdomen region were used from the PACS archives of Selcuk University Medical Faculty Hospital. Images of 838 patients (464 females and 374 males) who had no hepatic pathologies were examined. Images were evaluated in terms of the presence of variations, and the cases were divided into groups, all of which were compared in terms of gender. Results: A previously unknown variation of the portal vein was detected in 4.9% of the patients: The left portal vein curved reversely after its origination from the main portal vein, supplying liver segments II and IV, after which it branched to supply segment III. In addition, four types of previously known variations of the portal vein were detected. Normal anatomic branching of portal vein was detected in 82.6% of the patients. Conclusion: A previously unknown variation was detected. Awareness of this variation and other known variations is significant in hepatic transplantation, surgery, and interventions.

Keywords

• Portal vein
• Multidetector CT
• Variation of the Portal Vein
• Couinaud segmentation
• Liver

Vena porta varyasyonlarının multidetector CT’de değerlendirilmesi

Öz

Amaç: Cerrahların, karaciğer müdahalelerini gerçekleştirirken kapsamlı bir vasküler anatomi ye sahip olmaları gereklidir. Karaciğer transplantasyonu operasyonu vasküler anatomi ve varyasyonlar hakkında iyi bir bilgi gerektirir. Bu çalışma amacı, bilinmeyen varyasyonları bulmak için portal venin intrahepatik dallanma paterninin değerlendirilmesidir. Yöntemler: Bu kesitsel çalışma, çok yönlü BT (MDCT) kullanan bir araştırma makalesidir. Karaciğer patolojisi olmayan 838 hastanın (464 kadın ve 374 erkek) çok dedektörlü BT görüntüleri incelendi. Görüntüler varyasyon varlığı açısından değerlendirildi. Sonuç olarak, vakalar gruplara ayrıldı. Tüm gruplar cinsiyete göre analiz edildi. Bulgular: Hastaların %4,9'unda daha önce bilinmeyen bir portal ven varyasyonu tespit edildi: sol portal ven, ana portal venden çıktıktan sonra ters yönde eğrilir. Karaciğerin II ve IV segmentlerini besler ve segment III'ü besler. Ayrıca, portal damarın önceden bilinen dört çeşidi de tespit edildi. Hastaların %82,6'sında portal vende normal anatomik dallanma bulundu. Sonuç: Önceden bilinmeyen bir varyasyon tespit edildi. Bu varyasyonun ve diğer bilinen varyasyonların farkında olunması, karaciğer transplantasyonu, cerrahi ve girişimlerde çok önemlidir.

Anahtar Kelimeler

• Portal ven
• Multidetector BT
• Portal ven varyasyonu
• Couinaud segmentasyonu
• Karaciğer

Kaynakça

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