Which is best method for instillation of topical therapy to the upper urinary tract? An in vivo porcine study to evaluate three delivery methods

Abstract

Purpose:To compare the staining intensity of the upper urinary tract (UUT) urothelium among three UUT delivery methods in an in vivo porcine model.Materials and methods:A fluorescent dye solution (indigo carmine) was delivered to the UUT via three different methods: antegrade perfusion, vesico-ureteral reflux via in-dwelling ureteric stent and retrograde perfusion via a 5F open-ended ureteral catheter. Twelve renal units were tested with 4 in each method. After a 2-hour delivery time, the renal-ureter units were harvested en bloc. Time from harvesting to analysis was also standardised to be 2 hours in each arm. Three urothelium samples of the same weight and size were taken from each of the 6 pre-defined points (upper pole, mid pole, lower pole, renal pelvis, mid ureter and distal ureter) and the amount of fluorescence was measured with a spectrometer.Results:The mean fluorescence detected at all 6 predefined points of the UUT urothelium was the highest for the retrograde method. This was statistically significant with p-value less than <0.05 at all 6 points.Conclusions:Retrograde infusion of UUT by an open ended ureteral catheter resulted in highest mean fluorescence detected at all 6 pre-defined points of the UUT urothelium compared to antegrade infusion and vesico-ureteral reflux via indwelling ureteric stents indicating retrograde method ideal for topical therapy throughout the UUT urothelium. More clinical studies are needed to demonstrate if retrograde method could lead to better clinical outcomes compared to the other two methods.

<p>Optimal Management of Upper Tract Urothelial Carcinoma: Current Perspectives</p>

“…In an attempt to reduce potential confounding factors of a lack of natural ureteral peristalsis and continuous urine production, and the absence of intra-abdominal pressure found in this ex-vivo study, 41 Liu et al investigated the staining intensity of the three methods in the collecting system at 6 pre-defined points (upper pole, mid pole, lower pole, renal pelvis, mid ureter, distal ureter) in an in-vivo porcine model. 42 Retrograde approach via an open-ended ureteric catheter resulted in the highest mean fluorescence detected at all the 6 pre-defined points compared to the other 2 methods and this was significant on statistical analysis. 42 More clinical studies are needed to determine which is the best method among the three.…”

“…42 Retrograde approach via an open-ended ureteric catheter resulted in the highest mean fluorescence detected at all the 6 pre-defined points compared to the other 2 methods and this was significant on statistical analysis. 42 More clinical studies are needed to determine which is the best method among the three.…”

New Approach Methods to Evaluate Health Risks of Air Pollutants: Critical Design Considerations for In Vitro Exposure Testing

“…Aspiration and instillation exposure routes are similar in that they involve the introduction of substances to the throat. Aspiration involves the introduction of substances into the region of the pharynx whereas instillation requires substances to be introduced directly into the trachea [27,28]. These methods have become widely used as they allow for greater control over dosage and location compared to other exposure routes, such as inhalation, though these routes have certain limitations.…”

UGN-101 (mitomycin gel): a novel treatment for low-grade upper tract urothelial carcinoma

“…24 One animal study suggested that retrograde instillation via ureteral catheter provided the best retention and coverage of the renal pelvis. 25 As discussed, the major barriers to effective administration of MMC lie in achieving an appropriate dwell time, and assuring drug distribution throughout the entire collecting system. 11 It remains unclear whether the reported outcomes and recurrence rates are reflective of true treatment response, or poor administration technique.…”