The risk factors associated with colonic injury during percutaneous renal stone surgery – a literature review

Objective: A focused literature review was conducted of colonic injuries occurring during percutaneous nephrolithotomy (PCNL) procedures to determine the importance of patient position, identifiable risk factors and methods to avoid colonic injury. Method: A MEDLINE literature search was performed from PubMed and Scopus databases to retrieve all articles relating to colonic injuries occurring during PCNL. Incidence of colonic injury, patient management, position, side of stone and recognised risk factors were compiled for analysis. Results: Of the 35,054 PCNLs carried out, 87 colonic perforations were identified, which results in a 0.25% chance of perforation. A total of 65.5% (57/87) of colonic perforations occurred during left-hand punctures, and 54.0% (47/87) occurred in the prone position. Retrorenal colon, posterior colon, previous renal tract surgery, horseshoe kidney and mobile kidneys were the most common risk factors identified. Discussion: The risk of colonic perforation during PCNL was 0.25% across these studies. It more commonly occurred in the prone position and on the left-hand side. Only four perforations were noted to be in the supine position. A retrorenal colon is implicated as the most common identifiable risk factor. Careful preoperative work-up, planning and intraoperative use of ultrasound combined with fluoroscopy is the best method of preventing a colonic injury. Level of evidence: Not applicable for this multicentre audit.

Percutaneous nephrolithotomy: implementation of digital insertion and dissection as an adjunct to the technique

BACKGROUND: Percutaneous nephrolithotomy (PCNL) was established as a minimally invasive treatment option for kidney stones in the 1970s and is considered a safe and effective procedure, with stone clearance rates of 78-95%. The ideal puncture should maximize the effectiveness of the procedure in terms of stone-free status and minimize the risk of complications. CLINICAL CASE: We present the case of a 36-year-old male patient with bilateral lower back pain. A CT urography scan was performed that revealed bilateral lithiasis. The stone on the right side was consistent with an incomplete staghorn stone and a right retrorenal colon was identified. Left flexible nephrolithotripsy and subsequent right percutaneous nephrolithotomy were performed. A puncture was made under fluoroscopic guidance supported by previous digital dissection of all layers of the abdominal wall until gaining access to the retroperitoneum. Colonic lesion was prevented and a tunnel through which the renal unit could be palpated was formed. CONCLUSIONS: The technique of digital insertion and dissection offers safe access to the renal unit that is useful in patients presenting with risk factors for a potential complication. KEYWORDS: Digital; Kidney; Lithiasis; Percutaneous nephrolithotomy.

Bilateral retrorenal colon-a case report

Ascending and descending colon normally lie in anterior pararenal space anterior to kidneys. Extension of colon behind kidney is rare. It is more frequently found on the left side behind lower pole of the left kidney. Bilateral retrorenal colon is rare. Its detection is important prior to Retrorenal, Percutaneous nephrolithotomy (PCNL) to avoid complications. We report a case of bilateral retrorenal colon detected incidentally in a case of obstructive jaundice.