MAUDE Adverse Event Report: BOSTON SCIENTIFIC CORPORATION REZUM; UNIT, ELECTROSURGICAL ENDOSCOPIC (WITH OR WITHOUT ACCESSORIES)

Model Number	M006D2201-0032
Medical Device Problem Code	Adverse Event Without Identified Device or Use Problem (2993)
Health Effect - Clinical Codes	Hematoma (1884); Urinary Retention (2119)
Date of Event	04/24/2026
Type of Reportable Event	Serious Injury
Additional Manufacturer Narrative
(2026).Therapeutic efficacy of water vapor energy therapy performed with benign prostatic hyperplasia.133rd annual meeting of the japanese urological association 2026.Pp-20-07.
Event or Problem Description
It was reported to boston scientific via an abstract presented in the 133rd annual meeting of the japanese urological association 2026, that a study was conducted to investigate the efficacy and safety of patients who underwent rezum water vapor thermal therapy procedure to treat benign prostatic hyperplasia.A total of 58 patients, with median age of 73 years old, were treated with rezum between (b)(6) 2024 and (b)(6) 2025 at one institution in japan.Following procedure, 1 patient who was taking anticoagulants prior to procedure, and continued the anticoagulant therapy during procedure, required a bladder irrigation for hematoma removal after discharge.Additionally, 2 patients had an additional photo selective vaporization of the prostate surgery performed as there was insufficient improvement from the initial rezum therapy.Urinary retention was observed in 6 patients after removal of the catheter that was placed after rezum therapy; however, all patients improved after reinsertion and removal of the catheter.
Event or Problem Description
It was reported to boston scientific via an abstract presented in the 133rd annual meeting of the japanese urological association 2026, that a study was conducted to investigate the efficacy and safety of patients who underwent rezum water vapor thermal therapy procedure to treat benign prostatic hyperplasia.A total of 58 patients, with median age of 73 years old, were treated with rezum between june 2024 and july 2025 at one institution in japan.Following procedure, 1 patient who was taking anticoagulants prior to procedure, and continued the anticoagulant therapy during procedure, required a bladder irrigation for hematoma removal after discharge.Additionally, 2 patients had an additional photoselective vaporization of the prostate surgery performed as there was insufficient improvement from the initial rezum therapy.Urinary retention was observed in 6 patients after removal of the catheter that was placed after rezum therapy; however, all patients improved after reinsertion and removal of the catheter.
Additional Manufacturer Narrative
(2026).Therapeutic efficacy of water vapor energy therapy performed with benign prostatic hyperplasia.133rd annual meeting of the japanese urological association 2026.Pp-20-07 detailed product information was not provided to bsc.Because the product is unknown at this time, we are unable to provide the complete unique identifier (udi) # and other product specific information.If additional details become available, a supplemental report will be submitted.The device was not available for analysis; therefore, no physical or visual analysis of the product could be performed.There was no reported device performance allegation.A ship history review was conducted and identified the following 38166776, 38009796, and 38191866 as potential lot numbers.The device history record (dhr) review confirmed that the devices with lot numbers 38166776, 38009796, and 38191866, met all material, assembly and performance specifications.A labeling review was completed, and the allegations of hematoma and urinary retention are listed in the device's instructions for use as adverse events related to device or procedure.A risk review was completed and confirmed that the events of hematoma and urinary retention were defined in the risk documentation and have been accounted for during product risk analysis to support acceptable risk benefit for the product.Based on the analysis findings, an investigation conclusion code of adverse event related to procedure was assigned to this investigation.

• Brand Name: REZUM
• Common Device Name: UNIT, ELECTROSURGICAL ENDOSCOPIC (WITH OR WITHOUT ACCESSORIES)
• Manufacturer (Section D): BOSTON SCIENTIFIC CORPORATION; 300 boston scientific way; marlborough MA 01752
• Manufacturer (Section G): BOSTON SCIENTIFIC CORPORATION; 4100 hamline ave. n.; st. paul MN 55112
• Manufacturer Contact: farshad fahimi ; 4100 hamline avenue north; building c; saint paul, MN 55112
• MDR Report Key: 25261877
• Report Number: 2124215-2026-27832
• Device Sequence Number: 14807048
• Product Code: KNS
• UDI-Device Identifier: 00191506006785
• UDI-Public: (01)00191506006785
• Combination Product (Y/N): N
• Initial Reporter Country: JA
• PMA/510(K) Number: K191505
• Number of Events Summarized: 1
• Summary Report (Y/N): N
• Serviced by Third Party (Y/N): Unknown
• Reporter Type: Manufacturer
• Report Source: Other,Foreign,Literature,Health Professional
• Initial Reporter Occupation: Physician
• Type of Report: Initial,Followup
• Report Date (Section B): 06/23/2026

1 Device was Involved in the Event

1 Patient was Involved in the Event

• Is this an Adverse Event Report?: Yes
• Is this a Product Problem Report?: No
• Operator of Device: Health Professional
• Device Model Number: M006D2201-0032
• Device Catalogue Number: M006D2201-0032
• Was Device Available for Evaluation?: No
• Is the Reporter a Health Professional?: Yes
• Type of Report(Section G): Thirty-Day
• Initial Date Received by Manufacturer: 04/24/2026
• Supplement Date Received by Manufacturer: 05/28/2026
• Initial Report FDA Received Date: 05/22/2026
• Supplement Report FDA Received Date: 06/23/2026
• Is the Device Labeled for Single Use? (Y/N): Yes
• Is This a Single-Use Device that was Reprocessed and Reused on a Patient? (Y/N): No
• Usage of Device: Initial
• Patient Sequence Number: 1
• Outcome Attributed to Adverse Event: Required Intervention
• Patient Age: 73 YR
• Patient Sex: Unknown