To assess whether morphometric and clinical parameters influence accessibility to the upper calyx through a lower calyx tract during supine percutaneous nephrolithotomy (SPCNL).
Data for 114 consecutive SPCNLs performed between 6/2014-3/2016 in an academic medical center were analyzed. Successful approachability was defined as rigid nephroscopic access to the upper calyx introduced through a lower calyx access as attested by direct visualization of the upper calyx papillae and position of the nephroscope on intraoperative pyelography. Demographic, morphometric and clinical parameters were assessed. Analysis of variance, Fisher's exact, chi-square tests, univariate and multivariate models were applied.
Successful approach was achieved in 94 (82%) patients. In univariate analyses previous kidney operations (p = 0.03), body weight (p = 0.04) and acute lower calyx access to the upper calyx axis angle (p = 0.01E-13) correlated with failed access. Multivariate analyses revealed that an acute angle was the sole independent factor for failed access (OR 1.4, p < 0.05; 95% CI 1.021-2.035). Limitations include the inability to objectively determine the mobility of the kidney as a co-factor in successful approachability.
SPCNL offers effective endoscopic accessibility through a lower calyx access. Previous kidney operations and body weight tend to negatively influence this accessibility. An acute angle between the lower calyx and the upper calyx is the single independent factor associated with failed accessibility.
Journal of endourology. 2017 Mar 14 [Epub ahead of print]
Mario Sofer, Yazeed Barghouthy, Yuval Bar-Yosef, Ishay Mintz, Silvia Proietti, Ronit Tsemah, Amir Horkin, Haim Matzkin, Guido Giusti
Tel-Aviv Sourasky Medical Center, Tel-Aviv University, Endourology Unit, Tel-Aviv, Israel ; ., Tel-Aviv Sourasky Medical Center, Tel-Aviv University, Urology, Tel-Aviv, Israel ; ., Tel-Aviv Sourasky Medical Center, Tel-Aviv University, Urology, Tel-Aviv, Israel ; ., Tel-Aviv Sourasky Medical Center, Urology, Tel-Aviv, Israel ; ., IRCCS San Raffaele Scientific Institute, Ville Turro Division, Dept of Urology , Viale Stamira d' Ancona , Milano, Italy , 28100 ; ., Tel-Aviv Sourasky Medical Center, Urology, Tel-Aviv, Israel ; ., Maagar Mochot Interdisciplinar Research Institute , Ramat-Gan, Israel ; ., TEL-Aviv Sourasky Medical Center, Tel-Aviv University, Tel-Aviv, Israel ; ., Ospedale San Raffaele, 9372, Department of Urology, IRCCS San Raffaele Scientific Institute, Ville Turro Division, Milan, Italy , via Stamira D'Ancona 20 , Milano, Italy , 20127.