The New Digital Flexible Ureteroscopes: ‘Size Does Matter’ – Increased Ureteric Access Sheath Use!

Abstract

Objectives: To evaluate whether the use of sheaths to access the ureter has increased after the introduction of new digital ureterorenoscopes in patients undergoing flexible ureteroscopy. Methods: 140 patients with kidney stones were randomised to be scoped with either an old-generation fibre-optic flexible ureteroscope (DUR-8, Elite, ACMI; distal tip diameter = 6.75 Fr) or a new-generation digital LCD flexible ureteroscope (Invisio D-URD flexible ureteroscope; distal tip diameter = 8.7 Fr). We recorded the necessity to use a sheath to access the ureter, sheath-related and postoperative complications, and whether or not a JJ stent was left behind. Results: 157 (80 fibre-optic and 77 digital) ureterorenoscopies were performed. Ureteral access sheaths were used significantly more frequently with digital scopes (p = 0.00174). Two patients in the digital scope group had a small distal ureteric perforation from the introducer sheath compared with none in the fibre-optic scope group. Conclusions: A statistically significant increase in sheath use was observed in the new-generation digital flexible ureteroscopy group. Despite the improvement in image quality, better durability and improved stone clearance, there are some potential drawbacks of these scopes. The increased distal tip diameter can result in increased use of ureteric access sheaths and this may increase morbidity and expense.

Renal Subcapsular Hemorrhage Complicating Ureterolithotripsy: An Unknown Complication of a Known Day-to-Day Procedure

“…The renal capsule then gradually separates from the parenchyma, and thus the hematoma is formed [7,9]. Another probable etiology of hemorrhage can be explained by injury due to guidewire access during ureteroscopy [5,10]. …”

CUA Guideline: Management of ureteral calculi

“…80 With the introduction of flexible digital ureteroscopes, with typical tip diameters of 8.4 to 8.7Fr broadening to a 9.9Fr shaft, there is an increasing need for ureteral orifice dilation and access sheath use. 81 In addition, the greater diameter may result in a higher likelihood of being unable to access and treat stones in the proximal ureter or renal pelvis/calyces. However, based on the available studies comparing larger digital flexible ureteroscopes with fibreoptic flexible ureteroscopes, the larger diameter did not affect stone-free rates and the digital ureteroscope resulted in shorter operative times.…”

Aftermath of Grade 3 Ureteral Injury from Passage of a Ureteral Access Sheath: Disaster or Deliverance?

“…Irrigation fluid flow rate increases up to sevenfold with increasing sheath diameter, 9 and the larger sheath facilitates passage of the larger digital or dual channel ureteroscopes while enabling the removal of stone fragments up to 4 mm in diameter. 10 …”