A new single-use digital flexible ureteroscope (LithoVue) compares favorably in performance to reusable scopes, at least for routine urteroscopy, with a possible advantage of being more economical. The experience of two institutions using the single-use ureteroscope was reported at the AUA annual meeting in Boston.
In a retrospective review of the first 75 cases with the 7.7F disposable flexible digital ureteroscope at the University of Southern California Institute of Urology and Norris Comprehensive Cancer Center, Los Angeles, study authors found its use to be satisfactory for the treatment of renal stones.
“We found that for our general stone cases, it works great,” said Eli Thompson, MD, urology resident at the University of Southern California. “It’s ergonomic and lightweight, and you can really torque on it without the fear of losing your scope by sending it off for a pricey repair if you break it.
“In the past year, this has become our ‘go to’ scope for our standard stone cases,” added Dr. Thompson, who worked on the study with Matthew D. Dunn, MD, and colleagues.
The reasons for ureteroscopy were stone disease in 60 patients, ureteral stricture disease in five patients, and upper tract transitional cell carcinoma in 10 patients. Ureteroscopy was initiated easily in all but three cases, one due to distal ureteral narrowing that required balloon dilation and two due to proximal ureter narrowing that required stenting. Two patients with ureteroenteric anastomotic disease required antegrade ureteroscopy.
Visualization problems included mild interference in the video system during laser lithotripsy of calcium oxalate monohydrate stones that did not prevent treatment. Use of the single-use ureteroscope is incompatible with electrocautery; during fulguration of upper tract transitional cell carcinoma, the use of a 3F electrode resulted in system reboot.
There was difficulty identifying the true lumen past the stricture with distant focusing during ureteroenteric anastomotic stricture, which led to inaccurate incision of the soft tissue resulting in extravasation.
“The new disposable ureteroscope works well for routine ureteroscopy with laser lithotripsy,” the investigators concluded, but should not be used with electrocautery and should be avoided for antegrade incision of ureteroenteric anastomotic stricture.
Separately, investigators from the University of Melbourne and Austin Hospital in Australia focused their analysis on ex vivo performance and cost-effectiveness of the LithoVue ureteroscope. They performed an analysis of reusable flexible ureteroscope damage with two commonly used instruments—the Olympus URF-V and the Storz Flex-Xc—at their institution over 30 months, assuming an initial purchase cost of $26,372 Australian and fixed cleaning costs of $26.23 per case. Repair costs were averaged as if happening to a single scope.
They found 15 instances of major ureteroscope damage with 234 cases performed over the 30 months. (Damage was considered major when the cost exceeded $10,000 Australian.) The mean number of cases performed before damage was 15.6. The total cost of repairs was $162,628 Australian. Including purchase price and repair costs, mean cost per case was $695 Australian.
“After 28 cases, the cost of using and maintaining a reusable flexible ureteroscope was approximately $50,000 (Australian); that’s about $34,000 U.S. dollars,” said lead investigator Damien Bolton, MD, head of surgery at Austin Hospital, Heidelberg, Victoria, Australia. If the price of the single-use ureteroscope is $1,200 Australian or less, it will be more economical than reusable flexible ureteroscopes, whereas it would not be economical if the price exceeded $2,500 Australian.
“I don’t know if this will be the ureteroscope for every stone case at every institution, but where you have stone cases where you are at high risk of damaging your valuable reusable scope, this clearly has a role,” he told Urology Times.
“The cases that caused major damage tended to be staghorn stones or partial stags, or stones in lower pole calyses, so I would recommend to consider that if you have a patient in whom you feel that you’re going to damage your very expensive reusable scope, you might use a single-use scope instead if it’s going to cost you less than $2,000,” said co-author Derek Hennessy, MD, clinical fellow at Austin Hospital.
With an empty working channel, range of movement was superior with the single-use instrument. Flexion of the single-use scope is 285° compared with 180° with the URF-V and 283° with the Flex-Xc. Deflection was 286°, 270°, and 219° for LithoVue, URF-V, and Flex-Xc, respectively. At 100 cm, irrigation flow with the single-use ureteroscope was superior to that of the reusable scopes. This superiority was maintained with a 200-µm Holmium laser fiber and a 1.9F stone basket in the channel.
The single-use scope displayed satisfactory ergonomics, maneuverability, and image quality in the treatment of renal stones in three patients. Complete stone fragmentation and clearance was achieved in all cases.