Ureteral diameter linked to ureteral injury during sheath placement

The proximal ureteral diameter is a significant predictor of high-grade ureteral injury during ureteral access sheath placement, with a smaller diameter increasing the risk and severity of such injury, according to a recent study.

The authors prospectively enrolled 68 patients in this study from July 2014 to September 2015. Participants underwent preoperative noncontrast computerized tomography and had a 12Fr to 14Fr ureteral access sheath placement without presenting.

Subsequently, two urologists and one radiologist measured the proximal ureteral diameter. Two endourologists evaluated ureteral wall injuries using the 5-grade classification.

Of the patients, 64 (94.1 percent) had a successful sheath placement. Forty-six of these individuals (71.9 percent) had evidence of any type of injury to the ureter wall, and 12 (26.1 percent) suffered from high-grade injuries. Among those who had a high-grade injury, the ureteral diameter was significantly smaller compared to individuals who had low-grade injuries (mean, 3.29±0.46 vs 4.5±0.97 mm; p<0.001).

In addition, multivariate analysis revealed that narrower proximal ureteral diameter correlated with a higher risk of high-grade ureteral injury (odds ratio, 2.8, 95 percent confidence interval, 1.9–3.4; p<0.001), regardless of age, gender, body mass index, and middle and distal ureteral diameter.

“[P]reoperative measurement of the ureteral diameter is recommended for ureteral access sheath placement to predict the risk of ureteral injury,” the authors said.