(104 days)
The Rezūm System is intended to relieve symptoms, obstructions, and reduce prostate tissue associated with benign prostatic hyperplasia(BPH). It is indicated for men ≥ 50 years of age with a prostate volume 30 cm³ ≤ 150 cm³. The Rezūm System is also indicated for treatment of prostate with hyperplasia of the central zone and/or a median lobe.
The Rezūm System is designed to treat patients with bothersome urinary symptoms associated with benign prostatic hyperplasia (BPH). The Rezūm System utilizes radiofrequency current to generate "wet" thermal energy in the form of water vapor, which is then injected into the transition zone and/or median lobe of the prostate tissue in controlled 9-second doses. The vapor that is injected into the prostate tissue rapidly disperses through the interstitial space between the tissue cells. As the vapor cools, it condenses immediately on contact with tissue and the stored thermal energy is released, denaturing the cell membranes and causing cell death.
The denatured cells are absorbed by the body, which reduces the volume of prostate tissue adjacent to the urethra. The vapor condensation process also causes a rapid collapse of vasculature in the treatment zone, resulting in a bloodless procedure.
Following thermal therapy for BPH, small pieces of coagulated tissue may slough off and be expelled via urination. This sloughing process may continue for a few months post-procedure depending on the rate of healing.
The Rezūm System consists of the following:
• Rezūm Generator – reusable, non-sterile capital equipment, provided with one power cord
• Rezūm Delivery Device Kit – sterile, single-use kit containing the following disposable components:
- One sterile Delivery Device with cable and tubing
- One sterile syringe
- One sterile spike adaptor
- One sterile water vial
The provided FDA 510(k) clearance letter and summary for the Rezūm System (K250584) focuses on an expanded indication for use, specifically for larger prostate volumes, rather than establishing acceptance criteria for a new device's performance. The information provided describes studies demonstrating the comparable safety and effectiveness of the device for this expanded range, rather than defining specific performance metrics against pre-defined acceptance criteria for a novel device.
Since the document is for an expanded indication and not a de novo clearance, the acceptance criteria are implicitly that the device performs similarly in safety and effectiveness in the expanded patient population as it did in the previously cleared population. The study's goal was to demonstrate this similarity.
Here's an analysis based on the provided text, outlining what can and cannot be extracted regarding acceptance criteria and performance data:
Acceptance Criteria and Device Performance
The concept of "acceptance criteria" in this context is less about a numerical threshold for a novel device's performance (e.g., sensitivity > X%, accuracy > Y%) and more about demonstrating that the device's safety and efficacy profile remains acceptable and comparable within the expanded patient population.
Implicit Acceptance Criteria:
- Safety: No new or unexpected adverse events in patients with prostate volumes >80 cm³ and ≤150 cm³. The rates of adverse events, including serious complications, should be generally similar to those observed in patients with prostate volumes ≤80 cm³.
- Effectiveness: Significant and similar improvements in functional and quality of life outcomes in patients with prostate volumes >80 cm³ and ≤150 cm³ compared to patients with prostate volumes ≤80 cm³. No negative impact on sexual function.
Reported Device Performance (as demonstrated by the supporting studies):
- Safety: "Patients with prostate volumes >80 cm³ had generally similar rates of adverse events, including serious complications. No unexpected adverse events were reported, and all adverse events were consistent with those reported in the Rezūm System pivotal clinical study."
- Effectiveness: "Significant and similar improvements in functional and quality of life outcomes were demonstrated in both patient populations, with no negative impact to sexual function."
Table of (Implicit) Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria Category | Implicit Acceptance Criterion | Reported Device Performance (from supporting studies) |
|---|---|---|
| Safety Efficacy | No new or unexpected adverse events in patients with prostate volumes >80 cm³ and ≤150 cm³. Rates of adverse events, including serious complications, generally similar to patients with prostate volumes ≤80 cm³. | Patients with prostate volumes >80 cm³ had generally similar rates of adverse events, including serious complications. No unexpected adverse events were reported, and all adverse events were consistent with those reported in the Rezūm System pivotal clinical study. |
| Functional & QoL Outcomes | Significant and similar improvements in functional and quality of life outcomes in the expanded population compared to the previously cleared population. | Significant and similar improvements in functional and quality of life outcomes were demonstrated in both patient populations (prostate volumes >80cm³ and ≤80 cm³). |
| Sexual Function | No negative impact on sexual function in the expanded population. | No negative impact to sexual function was observed in the expanded population. |
Study Details:
The document describes two types of clinical evidence used to support the expanded indication:
- Systematic review and meta-analysis of clinical studies: This reviewed existing data on the Rezūm System for patients with prostate volumes >80 cm³ and compared outcomes to patients with prostate volumes ≤80 cm³.
- Manufacturer-sponsored prospective, non-randomized, single-arm study: This study specifically evaluated the safety and effectiveness of the Rezūm System in patients with prostate volumes >80 cm³ and ≤150 cm³. The results were compared to data from the Rezūm System's original "pivotal clinical study."
Based on the provided text, here's what can be answered for each point:
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Sample size used for the test set and the data provenance:
- Systematic Review/Meta-analysis: The text does not specify the exact sample size. It states it was a "systematic review and meta-analysis of clinical studies," implying a pooling of data from multiple studies. The data provenance (country of origin, retrospective/prospective) is not specified for the individual studies included in the meta-analysis, but they are existing clinical studies.
- Manufacturer-sponsored study: The text does not specify the exact sample size. It describes the study as "prospective, non-randomized, single-arm." It evaluates patients with prostate volumes >80 cm³ and ≤150 cm³. Data provenance is primarily domestic, as it's a manufacturer-sponsored study submitted to the FDA. It is prospective.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
The Rezūm System is a therapeutic device (for relieving symptoms and reducing prostate tissue), not a diagnostic algorithm. Therefore, "ground truth" in the typical sense of expert label annotations for images or diagnostic classifications is not directly applicable here. The outcomes (symptom relief, prostate tissue reduction, adverse events, quality of life, sexual function) are assessed directly from patient reports, objective measurements (e.g., prostate volume changes), and clinical evaluations by treating physicians. The text does not mention a specific "ground truth" panel of experts, nor would it typically be required for a therapeutic device study focused on clinical outcomes. -
Adjudication method (e.g., 2+1, 3+1, none) for the test set:
Not applicable (N/A). As a therapeutic device focusing on direct clinical outcomes, adjudication methods like those used for diagnostic algorithms (e.g., for image interpretation) are not described or typically relevant in this context. Clinical events and outcomes are recorded based on predefined criteria, and adverse events are typically reported and classified by investigators and reviewed by safety committees. -
If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:
Not applicable (N/A). This is a therapeutic device, not an AI-powered diagnostic tool. Therefore, a multi-reader multi-case study comparing human readers with and without AI assistance is not relevant to this submission. -
If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
Not applicable (N/A). This is a therapeutic medical device, not an algorithm. The Rezūm System is a physical device used in a procedure performed by a human clinician. -
The type of ground truth used (expert concensus, pathology, outcomes data, etc):
As explained in point 3, the concept of "ground truth" for a therapeutic device is different. For this submission, the "ground truth" and evidence of effectiveness and safety comes from:- Clinical Outcomes Data: Patient-reported symptoms, quality of life scores, measures of sexual function, and potentially objective measures like post-treatment prostate volume.
- Adverse Event Reporting: Documentation and classification of adverse events.
- Comparison to a Pivotal Clinical Study: The study for the expanded indication compared its outcomes to those established in the device's original pivotal clinical study.
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The sample size for the training set:
Not applicable (N/A). This is a therapeutic medical device; there is no "training set" in the context of machine learning or AI algorithms. The development of the device itself would have involved engineering, preclinical, and early human studies, but these are not referred to as a "training set." -
How the ground truth for the training set was established:
Not applicable (N/A), as there is no "training set" in the AI/ML context for this device.
§ 876.4300 Endoscopic electrosurgical unit and accessories.
(a)
Identification. An endoscopic electrosurgical unit and accessories is a device used to perform electrosurgical procedures through an endoscope. This generic type of device includes the electrosurgical generator, patient plate, electric biopsy forceps, electrode, flexible snare, electrosurgical alarm system, electrosurgical power supply unit, electrical clamp, self-opening rigid snare, flexible suction coagulator electrode, patient return wristlet, contact jelly, adaptor to the cord for transurethral surgical instruments, the electric cord for transurethral surgical instruments, and the transurethral desiccator.(b)
Classification. Class II (performance standards).