PREOPERATIVE EVALUATION OF LIVING DONOR KIDNEY VARIATIONS WITH MULTIDETECTOR COMPUTED TOMOGRAPHY AND COMPARISON OF RESULTS WITH INTRAOPERATIVE FINDINGS

Öz

OBJECTIVE: The aim of this study was to evaluate the renal vascular and collecting system variations in living kidney donors using multidetector computed tomography (MDCT) and to compare the data with the findings detected during retroperitoneoscopic donor nephrectomy. MATERIAL AND METHODS: Between January 2015 and October 2021, 652 living donors who underwent retroperitoneoscopic donor nephrectomy at our center and had preoperative MDCT imaging were included in the study. Arterial, venous, and collecting system variations in the kidneys were detected in MDCT, and the results were compared with the intraoperative findings. RESULTS: Left nephrectomy was performed in 72.7% (474 individuals) of the donors, and right nephrectomy was performed on the remaining 178 donors (27.3%). While 99 (15.1%) of the 652 transplanted kidneys had double arteries, 11 (1.6%) had three arteries, and 1 (<1%) had four arteries; early arterial segmentation was detected in 14 (2.1%) kidneys. According to laparoscopic findings, there were double renal veins in 26 (4%) donor kidneys and three renal veins in 3 (0.4%) kidneys. Also structural venous variation was seen in 8 donors and collector system variation was seen in 6 donors. The sensitivity, specificity, positive-negative predictive value and accuracy of MDCT in detecting the presence of accessory arteries were; 97.3%, 98.5%, 93.1%, 99.4% and 98.3%, respectively. Its accuracy in detecting arterial counts was calculated as 98%. The sensitivity, specificity, positive-negative predictive value and accuracy rates of MDCT in detecting numerical variation in veins were; 100%, 99.8%, 96.5%, 100% and 99.8%, respectively. The accuracy in detecting the count of veins was calculated as 99.8%. 100% success was achieved in detecting arterial early segmentation, late venous confluence and collecting system variations. CONCLUSIONS: MDCT performed with the right technique is a very accurate method for the evaluation of renal vascular and collecting system variations in living-donor candidates for kidney transplantation.

Anahtar Kelimeler

• Living donor
• MDCT
• Artery
• Vein
• Collector system
• Variation

CANLI BÖBREK DONÖR VARYASYONLARININ ÇOK KESİTLİ BİLGİSAYARLI TOMOGRAFİ İLE PREOPERATİF DEĞERLENDİRİLMESİ VE SONUÇLARIN İNTRAOPERATİF BULGULAR İLE KARŞILAŞTIRILMASI

Öz

AMAÇ: Bu çalışmayla, çok kesitli bilgisayarlı tomografi (ÇKBT) kullanarak canlı böbrek donörlerinde renal vasküler ve toplayıcı sistem varyasyonlarını değerlendirmek ve verileri retroperitonoskopik donör nefrektomisinde saptanan bulgular ile karşılaştırmak amaçlanmıştır. GEREÇ VE YÖNTEM: Çalışmaya, Ocak 2015 ile Ekim 2021 arasında merkezimizde retroperitonoskopik donör nefrektomisi olan ve operasyon öncesi uygun protokol ile gerçekleştirilmiş ÇKBT görüntülemesi mevcut olan 652 donör dahil edildi. Böbreklerdeki arteryel, venöz ve toplayıcı sistem varyasyonları ÇKBT incelemesiyle değerlendirilip not edilerek sonuçlar operasyon bulguları ile karşılaştırıldı. BULGULAR: Donörlerin %72,7’sine (474 kişi) sol nefrektomi, kalan 178 donöre (%27,3) ise sağ nefrektomi yapıldı. Nakledilen 652 böbreğin 99’unda (%15,1) çift arter, 11’inde (%1,6) üç arter ve 1’inde (%<1) dört arter mevcut iken; 14 (%2,1) böbrekte erken arteryel segmentasyon saptandı. Laparoskopik bulgulara göre 26 (%4) donör böbrekte çift renal ven, 3 (%0,4) böbrekte üç adet renal ven mevcut iken; 8 donörde yapısal venöz varyasyon ve 6 donörde toplayıcı sistem varyasyonu görüldü. Aksesuar arter varlığını saptamada, ÇKBT’nin duyarlılık, özgüllük, pozitif-negatif öngörü değeri ve doğruluk oranları sırasıyla %97,3; %98,5; %93,1; %99,4 ve %98,3 olarak bulundu. Arter sayılarını saptamadaki doğruluğu ise %98 olarak hesaplandı. Venlerdeki sayısal varyasyonu saptamada ÇKBT’nin duyarlılık, özgüllük, pozitif-negatif öngörü değeri ve doğruluk oranları sırasıyla %100; %99,8; %96,5; %100 ve %99,8 olarak bulundu. Ven sayılarını saptamadaki doğruluğu ise %99,8 olarak hesaplandı. Arteryel erken segmentasyon, geç venöz konfluens ve toplayıcı sistem varyasyonlarını tespit etmede ise %100 başarı sağlandı. SONUÇ: Doğru teknik ile gerçekleştirilen ÇKBT, canlı donör böbrek nakli için donör adaylarında renal vasküler ve toplayıcı sistem varyasyonlarının değerlendirilmesi için oldukça doğru bir yöntemdir.

Anahtar Kelimeler

• Canlı donör
• ÇKBT
• Arter
• Ven
• Toplayıcı sistem
• Varyasyon

Kaynakça

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