Iatrogenic upper urinary tract injuries during ureteroscopy for urolithiasis: a comprehensive review on incidence, mechanisms and preventative strategies

The incidence of urolithiasis is increasing globally, with a prevalence of 13% in North America and 9% in Europe. Ureteroscopy is a minimally invasive approach for treating conditions affecting the upper urinary tract, including urolithiasis, for which its efficacy and safety is well recognized. There is a risk of complications associated with ureteroscopy, including iatrogenic mechanical ureteric injuries. These injuries are multifactorial in nature, with ureteroscopes and auxiliary endoscopic equipment having an important role, in addition to patient and stone factors. Excessive friction and insertion forces during ureteroscope and ureteric access sheath insertion, apparatus malfunction or thermal injuries during laser lithotripsy might cause injury to the upper urinary tract. Ureteric avulsion is a serious event, which necessitates further intervention such as ureteric reimplantation or nephrectomy. Ureteric mucosal injuries can be managed with a period of ureteric stenting, although stent-related symptoms can be challenging for patients. The ability of endoscopic equipment to injure the ureter is an area that requires further study to reduce incidence and minimize patient morbidity. In this article, we review the operative mechanisms that contribute to iatrogenic mechanical ureteric injuries and discuss preventative strategies.