(654 days)
Adjunctive use in the palliative treatment of post-operative pain and edema in superficial soft tissue.
SofPulse (912-M10, Roma3 and Torino II) devices are shortwave diathermy medical devices which apply to the body electromagnetic energy at a radio frequency (RF) of 27.12 MHz for the treatment of medical conditions by means other than the generation of deep heat within body tissues, i.e., by athermal means. The SofPulse models were designed to deposit mean radio frequency energy in tissue which is equivalent to that of the predicate MRT device. All of the SofPulse options deliver the RF signal to the tissue farget via inductive coupling with an applicator coil. SofPulse devices are portable and treatment can occur directly through dressings, clothing, casts, compression garments or supports.
Here's an analysis based on the provided document, addressing your questions about the acceptance criteria and study details for the Ivivi SofPulse device (K070541):
Summary of Device and Regulatory Context:
The Ivivi SofPulse (Models 912-M10, Roma3, and Torino II) is a shortwave diathermy medical device (now reclassified as nonthermal shortwave therapy, SWT) that applies electromagnetic energy at a radio frequency of 27.12 MHz. It's intended for "adjunctive use in the palliative treatment of post-operative pain and edema in superficial soft tissue" by athermal means. This device was determined to be substantially equivalent to the predicate device, MRT (K903675).
1. Table of Acceptance Criteria and Reported Device Performance
The provided document describes a 510(k) submission, which primarily focuses on demonstrating substantial equivalence to a predicate device, rather than establishing specific acceptance criteria (e.g., a certain sensitivity, specificity, or clinical outcome threshold) as would be seen for a novel device or a device requiring a PMA.
For devices demonstrating substantial equivalence, the "acceptance criteria" are implicitly met by demonstrating that the new device is as safe and effective as the predicate device. The performance is compared to the predicate's established characteristics.
Therefore, the table below presents the technological characteristics of the SofPulse and its predicate, which served as the basis for determining substantial equivalence.
| Characteristic | Acceptance Criteria (Predicate: MRT K903675) | Reported Device Performance (SofPulse K070541) |
|---|---|---|
| Underlying Technology | Deposit athermal RF energy in tissue | Deposit athermal RF energy in tissue |
| How Energy Deposited | Induction (coil applicator) | Induction (coil applicator) |
| Non-thermal Means | Yes | Yes |
| Risk | Low | Negligible (via Risk Analysis) |
| Carrier Frequency | 27.12 MHz | 27.12 MHz |
| Mean Duty Cycle | 2.3% | 2.5% |
| Energy Deposited Per Pulse | 6.8 µWs/cm³ | 6.5 µWs/cm³ |
| Treatment Duration | 5 - 30 min | 5 - 30 min |
| Power Source | Mains only | Battery or Mains |
| Portability | Yes | Yes |
| Intended Use/Indications For Use | Adjunctive use in the palliative treatment of post-operative pain and edema in superficial soft tissue. | Adjunctive use in the palliative treatment of post-operative pain and edema in superficial soft tissue. |
Study Proving Acceptance Criteria:
The document states: "Equivalence of performance of the SofPulse and MRT was demonstrated with bench testing in saline tissue equivalents and with an animal model validated for evaluation of pain and edema." This implies these studies were conducted to show that the SofPulse performs comparably to the predicate MRT device across the listed technological characteristics and intended effects on pain and edema.
2. Sample Size Used for the Test Set and Data Provenance
The document explicitly mentions:
- Bench testing in saline tissue equivalents: No sample size is provided for this. These are typically in-vitro, controlled experiments.
- Animal model validated for evaluation of pain and edema: No sample size is provided for the animal study (e.g., number of animals). The document does not specify the species or country of origin for the animal model.
- Data Provenance: Not explicitly stated (e.g., country of origin, retrospective/prospective). However, animal model studies are prospective by nature.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The document does not suggest the use of human experts to establish "ground truth" for the test set in the way one would for diagnostic imaging. Instead, the "ground truth" for demonstrating equivalence in an animal model would likely be objective physiological measurements of pain and edema (e.g., paw swelling, behavioral responses to pain stimuli, biochemical markers). Therefore, information about experts and their qualifications in this context is not applicable.
4. Adjudication Method (e.g., 2+1, 3+1, none) for the Test Set
The concept of an "adjudication method" (like 2+1 or 3+1) is relevant for clinical studies where human readers or evaluators make subjective judgments that need to be reconciled. Since the studies mentioned are bench testing and an animal model, such an adjudication method would not be applicable.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No. The document describes bench testing and an animal model study, not an MRMC study. MRMC studies are typically performed for diagnostic devices where human reader performance is a key metric.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
The device is a therapeutic (nonthermal shortwave therapy) device, not a diagnostic algorithm. Therefore, the concept of "standalone performance" for an algorithm without human-in-the-loop is not applicable here. The device operates independently on the patient, but its effectiveness is clinically evaluated, not algorithmically.
7. The Type of Ground Truth Used
Based on the description of the studies:
- Bench Testing: Ground truth would be based on physical measurements (e.g., RF energy deposited, duty cycle measured by instrumentation) in a controlled environment (saline tissue equivalents).
- Animal Model: Ground truth would be based on objective biological/physiological measurements of pain and edema relief (e.g., quantified reduction in swelling, validated pain scales/responses, inflammatory markers).
8. The Sample Size for the Training Set
The document does not mention a "training set." This term is typically used in the context of machine learning or AI development. The studies mentioned (bench testing, animal model) are for verification and validation of the device's performance against its predicate, not for training a model.
9. How the Ground Truth for the Training Set Was Established
As there is no mention of a training set, this question is not applicable.
§ 890.5290 Shortwave diathermy.
(a)
Shortwave diathermy for use in applying therapeutic deep heat for selected medical conditions —(1)Identification. A shortwave diathermy for use in applying therapeutic deep heat for selected medical conditions is a device that applies to specific areas of the body electromagnetic energy in the radiofrequency (RF) bands of 13.56 megahertz (MHz) or 27.12 MHz and that is intended to generate deep heat within body tissues for the treatment of selected medical conditions such as relief of pain, muscle spasms, and joint contractures, but not for the treatment of malignancies.(2)
Classification. Class II (performance standards).(b)
Nonthermal shortwave therapy —(1)Identification. A nonthermal shortwave therapy is a prescription device that applies to the body pulsed electromagnetic energy in the RF bands of 13.56 MHz or 27.12 MHz and that is intended for adjunctive use in the palliative treatment of postoperative pain and edema of soft tissue by means other than the generation of deep heat within body tissues as described in paragraph (a) of this section.(2)
Classification: Class II (special controls). The device is classified as class II. The special controls for this device are:(i) Components of the device that come into human contact must be demonstrated to be biocompatible.
(ii) Appropriate analysis/testing must demonstrate that the device is electrically safe and electromagnetically compatible in its intended use environment.
(iii) Non-clinical performance testing must demonstrate that the device performs as intended under anticipated conditions of use. Non-clinical performance testing must characterize the output waveform of the device and demonstrate that the device meets appropriate output performance specifications. The output characteristics and the methods used to determine these characteristics, including the following, must be determined:
(A) Peak output power;
(B) Pulse width;
(C) Pulse frequency;
(D) Duty cycle;
(E) Characteristics of other types of modulation that may be used;
(F) Average measured output powered into the RF antenna/applicator;
(G) Specific absorption rates in saline gel test load or other appropriate model;
(H) Characterization of the electrical and magnetic fields in saline gel test load or other appropriate model for each RF antenna and prescribed RF antenna orientation/position; and
(I) Characterization of the deposited energy density in saline gel test load or other appropriate model.
(iv) A detailed summary of the clinical testing pertinent to use of the device to demonstrate the effectiveness of the device in its intended use.
(v) Labeling must include the following:
(A) Output characteristics of the device;
(B) Recommended treatment regimes, including duration of use; and
(C) A detailed summary of the clinical testing pertinent to the use of the device and a summary of the adverse events and complications.
(vi) Nonthermal shortwave therapy devices marketed prior to the effective date of this reclassification must submit an amendment to their previously cleared premarket notification (510(k)) demonstrating compliance with these special controls.