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Updated: Aug 2, 2025

Photoselective Vaporesection of the Prostate via an End-firing Lithium Triborate Crystal Laser
Published on: May 9, 2018
Change in Prostate Volume and Symptom Improvement in Men Treated With Rezūm Water Vapor Therapy
Dean Elterman1, Naeem Bhojani2, Bilal Chughtai3
1Division of Urology, University Health Network, University of Toronto, Toronto, Ontario, Canada.
Objective:
To evaluate the change in prostate volume (PV) and relationship to improvement in urinary symptom scores following Rezūm therapy.
Methods:
Quality of life outcomes and PV were assessed at baseline and 12months postprocedure. Percent change from baseline in outcomes and PV were calculated, as was the number of Rezum injection to baseline PV ratio. Association between total number of injections and changes in outcomes and PV were evaluated using linear regression models.
Results:
A total of 49 men (mean age=67.8; standard deviation=9.4) underwent the procedure between April 2019 and September 2020, with a median baseline PV of 71.5 cc (range 24-150) and median number of vapor injections of 11.0 (range 4-21). At 12months, the median percent change in PV was - 34.0% (interquartile range: -49.2%, -16.7%), with 45/49 (91.8%) patients having reduced volume. Among the 45 patients with reduced volume at 12months, every 10% increase in volume reduction was associated with a 7.5% (95% confidence interval, 1.4%-13.6%; P = .02) improvement in the International Prostate Symptom Score. There was no significant association between total number of injections or injection to baseline volume ratio and change in PV.
Conclusion:
In this cohort of men treated with Rezūm therapy for benign prostatic hyperplasia, it was demonstrated that there is a correlation between greater PV reduction and greater symptomatic improvement. This study showed no association between more injections or the ratio of injections to PV changes, refuting the claim that more injections are better.
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