A novel ex vivo model For percutaneous renal surgery

Abstract

Objective To lessen the learning curve of percutaneous renal lithotripsy(PCNL),we introduced a novel ex-vivo learning and training model for PCNL under fluoroscopy and ultrasonography-guided access. Methods The model was set up nailing an adult porcine kidney with＞3 cm ureter (freshly removed from the slaughtering factory),with a full thickness flap of the thoracic wall or abdomen wall with two ribs,to a board.The porcine kidney was placed within the flap with the catheterized ureter outside.The kidney was enclosed by the flap so as to create a roodel for percutaneous renal surgery;with the ribs overlying the upper portion of the kidney.The model was fixed to the board by two nails.Artificial stone material was implanted in the renal pelvis.Fluoroscopy guidance access:Retrograde pyelography via injection of contrast medium into the ureteral catheter images the collecting system. After the long axis of the target calyx is identified,the C-arm is rotated 30 degrees toward the surgeon,placing the C-arm axis in the same posterior plane of the kidney.The needle is advanced in the plane of the fluoroscopic beam,and the appropriate needle placement is determined by obtaining a bull's-eye sign on the fluoroscope screen. Rotating the C-arm to a vertical position monitors the depth of the needle penetration. Ultrasonography guidance access:The renal pelvis can he filled with normal saline through a catheter to simulate hydronephrosis and the target calyx is identified under ultrasonography guidance.The tract dilation and stone disintegration were followed.After training,the kidney can be opened to examine the target calyx and the complication of dilation. Results Altogether,126 urologists attended a urologic endoscopic technique training course.Of the 126 trainees,104 (82.5%) successfully performed the whole percutaneous procedure.At the end of training,114 (90.5 %) of the 126 attendees rated the porcine kidney model for simulation of percutaneous renal surgery as very helpful or helpful.Conclusions This biological training model simulates realistically the clinical procedure of PCNL with respect to trainee experience in a low stress environment that provides an opportunity for repetitive performances in order to learn basic technical skills for the clinical procedure of PCNL in the future. Key words: Percutaneous nephrolithotomy; Models,anatomic; Training programs