In vitro, in vivo, and clinical tests of a novel flexible ureteroscope for the diagnosis and treatment of kidney and ureteral diseases.

Although we observed that two of the three performance parameters of the novel ureteroscope 'HF-EH' were inferior to those of the conventional ureteroscope, we successfully used HF-EH to perform retrograde intrarenal surgeries in patients. Further studies on performance and durability are warranted for making HF-EH commercially available.