(128 days)
The MyoScience Cryo-Touch is used to produce lesions in peripheral nervous tissue by the application of cold to the selected site for the blocking of pain. The Cryo-Touch is nog indicated for treatment of central nervous system tissue.
The MyoScience Cryo-Touch is a hand-held, single patient-use disposable, cryogenic device used to destroy nervous tissue or produce lesions in peripheral nervous tissue by the application of cold to the selected site for the purposes of blocking pain. The Cryo-Touch has been developed for applications in cryoanalgesia. Cryoanalgesia for intractable pain involves the location and freezing of the nerve associated with the pain. The device is based on introduction of a cryoprobe cooled by the cryogenic fluid (liquid nitrous oxide (N₂Q)) to the selected site and activation of the freeze control. An iceball forms around the tip of the needle assembly and the adjacent nerve. The Cryo-Touch may be used with a standard off-the-shelf nerve stimulator device in applications where precise nerve location is desired.
The MyoScience Cryo-Touch is a cryogenic surgical device intended to produce lesions in peripheral nervous tissue by applying cold to block pain. The submission, K100447, describes modifications to a previously cleared device (K083493), specifically the addition of a proprietary internal filter and an enhanced target treatment temperature of -65°C.
1. A table of acceptance criteria and the reported device performance
The provided document does not explicitly state quantitative acceptance criteria in a table format with specific thresholds (e.g., "temperature must be -65°C +/- 2°C"). Instead, it describes general design requirements and performance goals. However, the key performance aspect highlighted for the modified device is its ability to achieve a specific temperature.
| Acceptance Criterion (Implicit) | Reported Device Performance |
|---|---|
| System Performance (General) | Met design requirements for system performance. |
| Temperature Profiling during Simulated Use Conditions | Met design requirements for temperature profiling. |
| Target Treatment Temperature within Range of Predicate Devices | Delivers a target treatment temperature of -65°C. This temperature is within the range of the other predicate devices (Cryo-PaC, Painblocker WA5000, and Neurostat), which target -55°C to -80°C. |
| Cryolesioning Effects on Peripheral Nerves | Evaluated impact on physiologic function and histologic changes in a preclinical rat model. |
| Safety (Biocompatibility) | Identical to predicate device, implying biocompatible patient-contacting materials. |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
- Sample Size: The document does not specify a distinct "test set" sample size for the verification testing. For the preclinical animal study, it mentions "a rat model" but does not provide the number of animals used.
- Data Provenance:
- Verification testing: Performed internally by MyoScience. The country of origin is not specified, but MyoScience is based in Redwood City, CA, USA, suggesting the testing was likely conducted in the USA.
- Preclinical animal study: Performed using a "rat model." The location of the study is not specified.
- Nature of data: Both verification testing and the preclinical animal study were prospective in nature, designed specifically to evaluate the device.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
This information is not provided in the submission. The studies described are non-clinical (device performance verification and animal study) and do not involve human expert interpretation for "ground truth" in the way a diagnostic AI device would.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
This information is not applicable/not provided as the described studies are non-clinical and do not involve human expert adjudication of a test set in the context of diagnostic accuracy.
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, a multi-reader, multi-case (MRMC) comparative effectiveness study was not performed. This submission is for a therapeutic cryogenic surgical device, not a diagnostic imaging AI algorithm that would typically involve human readers. The study focuses on the device's physical performance and biological effect, not on human interpretation or decision-making.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
This question is not applicable as the device is a physical surgical instrument, not a standalone algorithm. The device's performance is inherently "standalone" in terms of its mechanical and thermal operation.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
- Verification Testing: The "ground truth" for system performance and temperature profiling would be based on engineering specifications and established measurement standards, comparing measured physical parameters to pre-defined design requirements.
- Preclinical Animal Study: The "ground truth" for evaluating the impact of cryotreatment on peripheral nerves would be based on physiological function assessments and histological changes observed in the rat model. This involves direct observation and analysis of biological tissue and function.
8. The sample size for the training set
This information is not applicable/not provided. This device does not employ machine learning or AI that would require a "training set." The development relies on engineering design, physical principles, and biological testing.
9. How the ground truth for the training set was established
This information is not applicable/not provided as there is no training set for this device.
§ 882.4250 Cryogenic surgical device.
(a)
Identification. A cryogenic surgical device is a device used to destroy nervous tissue or produce lesions in nervous tissue by the application of extreme cold to the selected site.(b)
Classification. Class II (performance standards).