(137 days)
The Sonata® Sonography-Guided Transcervical Fibroid Ablation System 2.1 is intended for diagnostic intrauterine imaging and transcervical treatment of symptomatic uterine fibroids, including those associated with heavy menstrual bleeding.
The Sonata® System 2.1 provides radiofrequency (RF) ablation of uterine fibroids using a transcervical approach that is uterine sparing, without incisions or material uterine distension. The system enables a clinician to deliver radiofrequency energy to fibroid tissue resulting in thermal fixation and coagulative necrosis of the tissue. The system combines two technologies - ultrasound for visualization, and radiofrequency energy for ablative therapy - in a single integrated handpiece. The Sonata® System 2.1is comprised of medical equipment, software, and various single-use and reusable instruments.
Here's a breakdown of the acceptance criteria and the study information for the Gynesonics Sonata® Sonography-Guided Transcervical Fibroid Ablation System 2.1, based on the provided FDA 510(k) summary:
The document (K193516) is a 510(k) premarket notification for the Sonata® Sonography-Guided Transcervical Fibroid Ablation System 2.1. It asserts substantial equivalence to a predicate device (Sonata® System, K173703) rather than presenting a novel device requiring a full clinical trial for de novo acceptance criteria. Therefore, the "acceptance criteria" here largely refer to the successful demonstration of the modified device's performance against its specifications and existing standards, and its equivalence to the predicate device's established safety and effectiveness.
1. Table of Acceptance Criteria and Reported Device Performance
Since this is a 510(k) submission asserting substantial equivalence and not a clinical trial establishing new efficacy, the "acceptance criteria" are generally met by demonstrating that the updated device performs equivalently or better than the predicate device and meets relevant performance standards.
| Aspect of Performance / Acceptance Criteria | Reported Device Performance (Sonata® System 2.1) | Original (Predicate) Performance (Sonata® System K173703) |
|---|---|---|
| Ablation Dimensions (via SMART Guide) | Consistent with established Ablation Zone (AZ) and Thermal Safety Border (TSB) in ex vivo non-perfused bovine tissue model. | Developed from ex vivo bench ablation data and in vivo peri- and pre-hysterectomy studies. |
| Acoustic Output (ISPTA) | 72.5 mW/cm² (under regulatory limit of 720 mW/cm²) | 162 mW/cm² (under regulatory limit of 720 mW/cm²) |
| Acoustic Output (MI) | 1.2 (under regulatory limit of 1.9) | 1.7 (under regulatory limit of 1.9) |
| Ultrasound Clinical Measurement Accuracy | Meets stated product specification for ultrasound clinical measurement accuracy. | (Not explicitly detailed for predicate in this context, but implied to be met) |
| Electrical Safety & EMC | Complies with updated international standards (e.g., IEC 60601-1 Ed 4) | Complied with earlier versions of international standards (e.g., IEC 60601-1 Ed 3) |
| Biocompatibility | Established for all changed patient-contacting devices; complies with updated ISO 10993 standards. | Complied with earlier versions of ISO 10993 standards. |
| Human Factors (Treatment Tasks) | Summative HF testing validated safety and effectiveness of user interface, labeling, and training for intended users/use contexts. | (Not explicitly detailed for predicate in this context, but implied to be met with earlier design) |
| Human Factors (Reprocessing Tasks) | HF summative testing for reprocessing validated for predicate device, deemed applicable to subject device (due to minor changes). | Validated that the system's reprocessing aspects were safe and effective. |
| Sterilization Efficacy | Validated for components provided sterile (RFA Handpiece, Cable, sterile IUUS Probes). | Validated for predicate components. |
| Shelf Life | RFA Handpiece: 1 year; RFA Cable: 1 year; Dispersive Electrode: 3 years; Sterile IUUS Probe: 1 year. | (Not explicitly detailed for predicate in this context, but established) |
2. Sample Size Used for the Test Set and Data Provenance
The document primarily relies on bench testing for the modified components and leverages clinical data from the predicate device.
- Bench Testing: Sample sizes are not explicitly stated for most individual bench tests (e.g., "ex vivo testing," "type testing"). However, for the Human Factors (HF) Evaluation for Treatment, 15 gynecologists participated.
- Data Provenance:
- Bench testing: Primarily ex vivo (bovine tissue models) and in vitro (phantoms, component testing) conducted by the manufacturer, Gynesonics, Inc.
- Human Factors Evaluation: Conducted with representative users (gynecologists).
- Clinical Data (Leveraged): The document explicitly states "No additional clinical study data was needed to validate the Sonata® System 2.1." It leverages clinical data from the predicate device, K173703, which was based on an IDE study (G140114, NCT02228174) with n = 147 subjects across 22 centers. This predicate clinical data would be considered prospective from the original study. The country of origin for the predicate clinical study is not specified in the provided text.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
- Bench Testing: "Ground truth" for bench tests is generally based on metrology, physical measurements, and adherence to engineering specifications and international standards. This does not involve human experts establishing ground truth in the diagnostic sense.
- Human Factors Evaluation: 15 gynecologists participated in the HF study. Their qualifications are described as "representative of typical users involved with performing RFA for fibroids and impacted by device changes." Specific years of experience or board certifications are not provided in this summary.
- Clinical Data (Leveraged from Predicate): For the predicate clinical study (n=147), ground truth would have been established through standard clinical diagnostic methods for uterine fibroids (imaging, pathology, physician assessment of symptoms and outcomes). The number and qualifications of experts involved in establishing this clinical ground truth are not detailed in this 510(k) summary, as it's leveraging previously cleared data.
4. Adjudication Method for the Test Set
- Bench Testing: Adjudication is typically against pre-defined specifications and standards; it does not involve expert consensus in the way a diagnostic study would.
- Human Factors Evaluation: The HF study assesses the device's usability and user-related risks. The "ground truth" here is whether the device can be used safely and effectively by typical users without critical errors. This is usually determined by observing user performance against a task list and assessing identified use errors by a Human Factors team. An explicit "adjudication method" like 2+1 or 3+1 is not applicable for this type of study.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and Effect Size of Human Readers Improve with AI vs. Without AI Assistance
- No, an MRMC comparative effectiveness study was not done.
- The Sonata® System 2.1 is an interventional medical device for fibroid ablation, not an AI-assisted diagnostic imaging device. Therefore, the concept of "human readers improve with AI vs. without AI assistance" is not applicable in this context. The integrated ultrasound is for real-time visualization and guidance during the procedure, not primarily for diagnostic interpretation by multiple readers.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
- The Sonata® System 2.1 is an interventional device with integrated imaging and ablation capabilities, inherently designed for human-in-the-loop operation. It's not a standalone diagnostic algorithm. The "SMART Guide" is a graphical overlay that assists the clinician, not an autonomous algorithm. Therefore, a standalone performance study without human-in-the-loop is not relevant or applicable for this device.
7. The Type of Ground Truth Used
- Benchmark Ground Truth: For the "SMART Guide" development and confirmation, ex vivo ablation dimensions in bovine tissue models served as a physical, measured "ground truth" to ensure the graphical representation (Ablation Zone, Thermal Safety Border) accurately reflects the physical effect of ablation.
- Conformance Ground Truth: For most other bench tests (electrical safety, biocompatibility, sterilization, mechanical testing), the "ground truth" is conformance to established international standards (e.g., ISO, IEC) and internal product specifications.
- Usability Ground Truth: For Human Factors studies, the ground truth is the demonstration that the device design, labeling, and training allow intended users to perform critical tasks safely and effectively, avoiding critical use errors.
- Clinical Ground Truth (Leveraged): For the predicate device's clinical trial (K173703), the ground truth for fibroid treatment effectiveness would have been based on clinical outcomes data (e.g., reduction in heavy menstrual bleeding, fibroid volume reduction, patient symptom scores) and potentially pathology for confirmed fibroid presence.
8. The Sample Size for the Training Set
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Training Set for SMART Guide (Algorithm/Graphical Overlay):
- Ex vivo testing with non-perfused bovine tissue models was used for preliminary development of the Ablation Zone (AZ) and Thermal Safety Border (TSB) dimensions. This would represent the "training" data for these graphical representations.
- In vivo peri- and pre-hysterectomy studies data were also used to "set final SMART Guide dimensions." The exact sample size for these in vivo studies specifically for SMART Guide development is not given, but they refer to the predicate's clinical experience. (Note: These would be considered part of the training/development of the SMART Guide, not necessarily the training of a machine learning algorithm).
-
No explicit "training set" in the machine learning sense is described for an AI algorithm for diagnostic purposes, as this is primarily a procedural device with graphical guidance, not an AI diagnostic tool.
9. How the Ground Truth for the Training Set Was Established
- For the SMART Guide:
- Ex vivo tissue models: Physical measurements of ablation zones created in bovine tissue.
- In vivo peri- and pre-hysterectomy studies: Clinical observation and potentially pathological examination of ablated tissue in human subjects. This would have been established through a combination of imaging (ultrasound, MRI), physician assessment, and potentially macroscopic/microscopic examination of excised tissue if a hysterectomy followed ablation. The specific methodology for establishing this "ground truth" for SMART Guide dimensions is not fully detailed in this 510(k) summary for the updated device, as it leverages prior work.
§ 884.4160 Unipolar endoscopic coagulator-cutter and accessories.
(a)
Identification. A unipolar endoscopic coagulator-cutter is a device designed to destroy tissue with high temperatures by directing a high frequency electrical current through the tissue between an energized probe and a grounding plate. It is used in female sterilization and in other operative procedures under endoscopic observation. This generic type of device may include the following accessories: an electrical generator, probes and electrical cables, and a patient grounding plate. This generic type of device does not include devices used to perform female sterilization under hysteroscopic observation.(b)
Classification. Class II (performance standards).