Ureteroscopy-assisted retrograde nephrostomy for an obese patient
A 63-year-old female with a left renal calculus was referred to our hospital. Radiography revealed a renal calculus (23 × 16 mm), as shown in Figure and . She had no remarkable previous or family history including obesity (158 cm, 85 kg). Her body mass index was 34.0 kg/m2 and laboratory data showed no remarkable findings. In February 2011, she was admitted to Department of Urology, Ohguchi Higashi General Hospital for PCNL to treat the left renal calculus.\nUnder general and epidural anesthesia, the patient was placed in a Galdakao-modified Valdivia position.[] A flexible ureteroscopy (Flex-X2, Karl Storz, Tuttlingen, Germany) was inserted through an 12 Fr (inner diameter) ureteral access sheath (FlexorÒ, 12 Fr, 35 cm, COOK Urological, IN, USA) inserted into the ureter. We carefully observed the target calculus and defined the appropriate position to puncture. A Lawson retrograde nephrostomy puncture wire (Cook Urological) was then set into the flexible URS. The scope was advanced to the desired calyx again and the puncture wire was driven along the route from the middle calyx to the exit skin. To avoid injury to the spleen, intestines, liver, and pleural cavity, the puncture was performed under ultrasonography. The puncture wire passed through the muscle easily and “tented” the skin at the posterior axillary line under fluoroscopic guidance. The skin was incised and the needle was delivered. Next, the dilator was placed over the puncture wire and advanced through the skin, subcutaneous fat, abdominal wall musculature, and perinephric fat until it reached the renal parenchyma under the URS. A 30 Fr percutaneous nephro access sheath (X-ForceÒ, Nephrostomy Balloon Dilation Catheter, BARD, NJ, USA) was passed over the balloon under continuous visualization with the URS. After inserting the nephro access sheath into the renal collecting system, calculus fragmentation was undertaken using the Swiss Litho ClastÒ lithotripter (EMS, Nyon, Switzerland) through a rigid nephroscope (percutaneous nephroscope, KarlStortz). The operation time was 171 minutes and no major or minor complications were noted. A postoperative kidney-ureter-bladder (KUB) film is shown in . Stone analysis revealed calcium phosphate and calcium oxalate.