(507 days)
The LipoSonix system delivers high intensity focused ultrasound (HIFU) energy that can disrupt subcutaneous adipose tissue (SAT) to provide a non-invasive approach to achieve a desired aesthetic effect. The LipoSonix system is specifically indicated for non-invasive waist circumference reduction.
The LipoSonix system is a cart-based system intended for non-invasive waist circumference reduction. The LipoSonix system uses ultrasound energy to disrupt subcutaneous adipose tissue (soft tissue). The system consists of a base, a treatment head (which contains the transducer) and a treatment arm in one unit.
Here's a breakdown of the acceptance criteria and study information for the LipoSonix® system Model 1, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Objective) | Reported Device Performance |
|---|---|
| Primary Endpoint: Superiority to sham control in reducing waist circumference. | The 59 J/cm² treatment group demonstrated a 1.01 cm greater waist circumference reduction as compared to sham. The least square (LS) mean change from baseline to 12 weeks of the waist circumference in the same 59 J/cm² group was -2.44 cm. On average, a mean change of approximately 2.55 cm (1 inch) compared to baseline was demonstrated in the 59 J/cm² treatment group. |
| Safety: Low incidence of serious adverse events (SAEs) or unanticipated adverse device effects (UADEs), with adverse events being mostly mild, short-lived, and resolving without incident. | AEs were mostly mild, short-lived in duration, and resolved without incident. There were no serious adverse events (SAEs) or unanticipated adverse device effects (UADEs) related to treatment with the investigational device through 24 weeks post-treatment. |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the exact sample size for the "test set" in the traditional sense of a split dataset for algorithm evaluation. However, it indicates that the device was evaluated in a "multicenter, randomized study." The specific number of participants in this study is not provided, nor is the country of origin. Given the context of a 510(k) submission, it's a prospective clinical trial.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not explicitly provided in the document. For a device like this, waist circumference measurements are typically taken by trained clinical staff using standardized protocols, rather than requiring expert consensus in the same way an imaging diagnostic might.
4. Adjudication Method for the Test Set
The document does not specify an adjudication method for the study results. Measurements like waist circumference are generally objective, and while there might be quality control checks on the measurement process, an adjudication panel for "ground truth" isn't typically used in this context.
5. 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
No, an MRMC comparative effectiveness study was not done. The LipoSonix system is a treatment device, not a diagnostic imaging device that involves human readers interpreting results. Therefore, the concept of "human readers improve with AI" does not apply here.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
Yes, the performance data presented is for the LipoSonix system as a standalone treatment device. The study evaluates the device's ability to reduce waist circumference compared to a sham control, without human-in-the-loop intervention in the treatment application itself (though a human operates the device).
7. The Type of Ground Truth Used
The ground truth used was objective measurement data: "waist circumference reduction" measured from baseline to 12 weeks, as well as adverse events monitored throughout the study.
8. The Sample Size for the Training Set
The document does not mention a "training set" in the context of an algorithm. The LipoSonix system is a physical device that delivers ultrasound energy, not an AI/algorithm-based diagnostic or predictive tool that requires a training set in the machine learning sense. The clinical study described evaluates the device itself, not a learned algorithm.
9. How the Ground Truth for the Training Set Was Established
As no training set (in the machine learning sense) is mentioned or relevant for this type of device, the method for establishing ground truth for a training set is not applicable.
§ 878.4590 Focused ultrasound stimulator system for aesthetic use.
(a)
Identification. A Focused Ultrasound Stimulator System for Aesthetic Use is a device using focused ultrasound to produce localized, mechanical motion within tissues and cells for the purpose of producing either localized heating for tissue coagulation or for mechanical cellular membrane disruption intended for noninvasive aesthetic use.(b)
Classification. Class II (special controls). The special control for this device is FDA's “Class II Special Controls Guidance Document: Focused Ultrasound Stimulator System for Aesthetic Use.” See § 878.1(e) for the availability of this guidance document.