Difficult Access in Endourology: Anatomical Challenges and Contemporary Management.

PURPOSE OF REVIEW: This review provides a comprehensive overview of difficult access in endourology. This focuses on anatomical factors that complicate endoscopic management of upper and lower urinary tract diseases and discussing strategies to manage these challenges. RECENT FINDINGS: Advances in preoperative imaging, three-dimensional reconstruction, flexible digital ureteroscopes, suction-assisted ureteral access sheaths, thulium fibre laser technology, miniaturized percutaneous techniques, and image-guided navigation have significantly improved management in patients with complex anatomy. Improved understanding of congenital and acquired anatomical variations has facilitated individualized surgical planning. Difficult access is a major determinant of operative success and complications in endourology. Anatomical challenges-including narrow ureters, tortuous ureters, lower pole anatomy, calyceal diverticula, horseshoe kidneys, urinary diversion, obesity, spinal deformity, and previous surgery-require preoperative assessment and selective intraoperative strategies. This review summarizes current evidence, practical technical solutions, emerging technologies, and future directions to optimize access, improve stone-free rates, minimize complications, and enhance patient outcomes in complex endourological cases.