Retro-renal colon: role in percutaneous access

Area of Science:

• Radiology
• Urology
• Anatomy

Background:

• Upper urinary tract procedures are frequently performed with patients in the prone position.
• Colon perforation is a known complication, with retrorenal colon incidence ranging from 10-20% in prone positioning.
• Computed tomography (CT) scans are the preferred imaging modality for evaluating retrorenal colon.

Purpose of the Study:

• To determine the occurrence of retrorenal colon at the study center.
• To assess the risk of colon injury during percutaneous kidney puncture at various levels.

Main Methods:

• A hospital-based, descriptive observational study.
• Review of CT abdomen scans in supine and prone positions for 700 patients from January 2013 to December 2013.
• Definition of retrorenal colon based on anatomical landmarks described by Prassopoulos et al.

Main Results:

• Retrorenal colon was identified in 2% of patients in supine position and 6.8% in prone position.
• The study included 350 patients in each position.
• Common indications for CT scans included pain abdomen, calculus disease, and carcinoma bladder.

Conclusions:

• The observed incidence of retrorenal colon suggests a potentially low occurrence, though the study sample size is limited.
• Multicenter, large-scale population-based studies are recommended to establish the definitive incidence and injury risks associated with retrorenal colon.