The invention relates to medical devices and methods of use thereof, such as for example, ureteroscopy. In one embodiment, the device is a safety ureteral access sheath and interventional catheter insertion with a force meter and a force disengagement mechanism. In another embodiment, the invention provides a method of examination or treatment for a condition in a subject, comprising providing a device comprising a ureteral access sheath (UAS) operably linked to a force meter and a force disengagement mechanism, and using the device to examine or treat the subject.