Koo KC, et al. - This study was aimed to gauge the effectiveness of preoperative α-blockade for reducing ureteral access sheath (UAS) insertion forces (UASIF). Researchers also assessed the upper limit required to avoid ureteral injury in such cases. Maximal UASIF could be reduced by preoperative α-blockade and slow sheath placement. A smaller diameter sheath possibly served as an alternative or the procedure could be ceased and followed later by pre-stented retrograde intrarenal surgery (RIRS), if the UASIF exceeded 600 g.