Adherent Perinephric Fat Is a Surgical Risk Factor in Laparoscopic Single-Site Donor Nephrectomy: Analysis Using Mayo Adhesive Probability Score

The host-related risk factors for surgical difficulty of partial nephrectomy include the presence of thick and adherent adipose tissue surrounding the kidney (adherent perinephric fat [APF]). The kidney and perirenal fat must be isolated in donor nephrectomy. Thus, APF is an important surgery-related factor. We analyzed whether the Mayo adhesive probability (MAP) score is related to APF and surgical outcomes in laparoscopic single-site donor nephrectomy (LESS-DN). Forty-six donors who underwent LESS-DN were selected. Determination of APF was based on a retrospective review of video-recorded surgical procedures during anterior perinephric fat dissection. The MAP score was evaluated from computed tomography images. Data regarding patient characteristics and operative outcomes were collected. We then examined the MAP score, APF, and related factors. Eleven patients (23.9%) had APF. The patients were divided into 2 groups (MAP score of 0 points and ≥ 1 point). The 2 groups showed significant differences in sex, age, body mass index, history of hypertension, and history of dyslipidemia. The operation time was significantly longer and the estimated blood loss volume was higher in patients with a MAP score of ≥ 1. Eight of 9 patients with a MAP score of ≥ 1 had APF. The only significant differences between patients with and without APF were in the body mass index, history of hypertension, and history of dyslipidemia. The operation time was significantly longer and the estimated blood loss volume was larger in patients with APF. The MAP score could be useful when predicting surgical difficulty in patients undergoing LESS-DN.