MP71-11 REZūM® SYSTEM WATER VAPOR TREATMENT FOR BENIGN PROSTATIC HYPERPLASIA: CHARACTERIZATION WITH MAGNETIC RESONANCE IMAGING AND 3D RENDERING

Abstract

You have accessJournal of UrologyBenign Prostatic Hyperplasia: Surgical Therapy & New Technology II1 Apr 2014MP71-11 REZūM® SYSTEM WATER VAPOR TREATMENT FOR BENIGN PROSTATIC HYPERPLASIA: CHARACTERIZATION WITH MAGNETIC RESONANCE IMAGING AND 3D RENDERING Lance Mynderse, Dennis Hanson, Richard Robb, Edwin Rijo Cedano, Dalibor Pacik, Gabriel Varga, Thayne Larson, and Christopher Dixon Lance MynderseLance Mynderse More articles by this author , Dennis HansonDennis Hanson More articles by this author , Richard RobbRichard Robb More articles by this author , Edwin Rijo CedanoEdwin Rijo Cedano More articles by this author , Dalibor PacikDalibor Pacik More articles by this author , Gabriel VargaGabriel Varga More articles by this author , Thayne LarsonThayne Larson More articles by this author , and Christopher DixonChristopher Dixon More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2014.02.2170AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES The Rezūm® System is a novel BPH transurethral therapy based on convective thermal energy transfer using water vapor (steam). The condensation of steam releases 540 calories of stored thermal energy / ml of H2O, releasing 208 calories of energy per 0.4 ml treatment, causing necrosis of the targeted areas. Historically, gadolinium-enhanced MRI has shown significant correlation with whole mount histopathology of the prostate following minimally invasive ablative therapies. The objectives were to validate the principle of phase-change convective thermal energy transfer to treat BPH patients, and assess the MRI detected lesion characteristics and prostate volume reduction. METHODS IRB approvals were obtained from 3 centers, and 65 men with BPH/LUTS enrolled in the pilot studies, 60 of which were consented for MRI review. One to 4 vapor injections / lobe, including the median lobe, if present, were delivered. Gadolinium-enhanced MRI’s were conducted at 1wk, 1, 3 and 6 mos to assess the location of the thermal lesions (TL) and perform volume measurements for total prostate (TPV), transition zone (TZV) and thermal lesions (TLV). MRI’s were analyzed and volumes computed via co-registered T2 and post-contrast T1 axial acquisitions using the Analyze® Image Visualization and Analysis System. RESULTS Thermal lesions were normally limited to the transition zone (TZ) and corresponded well to the targeted treatment locations. Mean TLV at 1 wk (n=54) was 8.9 cc (range 0.5-35.1cc) and decreased by 59% at 1 mo (n= 51) and by 92% at 3 mos (n=28) and 96% at 6 mos (n=27). Mean TZV at 1 wk (n=54) was 41.2cc (range 9.1-113cc) and decreased by 17.2% at 1 mo (n=51) and 26.2% at 3 mos (n=28) and 34% at 6 mos (n=28). Mean TPV at 1 wk (n=54) was 69.7cc (range 20-169cc) decreased by 13.6% at 1 mo (n= 51) and by 19.9% at 3 mos (n=28) and 27.3% at 6 mos (n=28). MRI analysis of the TL demonstrated an excellent anatomic safety profile. The MRIs of 2 patients demonstrated extra-prostatic TL at the bladder neck, likely from vapor delivered outside the TZ, visible at 1 wk and 1 mo, but totally resolved by 3 mos. No adverse clinical sequelae were evident in these patients. CONCLUSIONS The Rezūm® System creates significant thermal lesions. Prostate MRI studies: 1.) Validated the principle of convective heating to generate TL, 2.) Documented treated tissue volumes, 3.) Confirmed near complete resolution of imaged lesions by 6 mos, 4.) Demonstrated reduction in TPV from baseline supporting probable clinical benefit, and 5.) Confirmed a favorable safety profile of this technology. © 2014FiguresReferencesRelatedDetails Volume 191Issue 4SApril 2014Page: e794 Advertisement Copyright & Permissions© 2014MetricsAuthor Information Lance Mynderse More articles by this author Dennis Hanson More articles by this author Richard Robb More articles by this author Edwin Rijo Cedano More articles by this author Dalibor Pacik More articles by this author Gabriel Varga More articles by this author Thayne Larson More articles by this author Christopher Dixon More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...