(136 days)
The Dermal Cooling System is a cryosurgical instrument intended for use in dermatologic procedures for the removal of benign lesions of the skin and for use when cooling is intended for the temporary reduction of pain, swelling, inflammation, and hematoma from minor surgical procedures.
The Dermal Cooling System is intended to be used by trained healthcare professionals.
The Dermal Cooling System is a cryosurgical device used to cool the skin, without the use of cryogenic gases or liquids, for the removal of benign skin lesions and for use when cooling is intended for the temporary reduction of pain, swelling, inflammation, and hematoma from minor surgical procedures. Surface contact cooling is achieved using a thermoelectric cooler (TEC), with an integrated aluminum plate, to lower the temperature of the skin. It is intended for use in a healthcare facility such as a clinic or doctor's office.
The Dermal Cooling System is comprised of the following components:
- control unit – houses user interface display, the system controller, and the power converters
- chiller – provides circulating coolant to the handpiece to remove heat from the TEC
- handpiece - contains the TEC, temperature sensors, the aluminum cooling plate, and user interface elements
- isolation transformer – isolates system from AC mains power
- cart – houses the isolation transformer, chiller, and control unit
The control unit initiates the treatment parameters and receives feedback from temperature sensors in the handpiece during the procedure. The user interface provides the mechanism for selection of the treatment plan, initiation of treatment, and display of treatment status.
The non-sterile, reusable handpiece contains the TEC which cools the aluminum contact plate to the treatment temperature, while the circulation of fluid past the TEC allows for the removal of heat. Thermistors affixed to the aluminum contact plate monitor the temperature at the treatment site.
The Dermal Cooling System has three operational modes: cooling off, pre-cool, and treatment. Cooling off represents the resting state; no power is supplied to the TEC in the handpiece. Pre-cool is the state during which the aluminum contact plate in the handpiece is cooled prior to treatment. Treatment is the normal treatment state in which the contact plate temperature is controlled to a pre-defined temperature defined in the treatment plan, as selected from the user interface on the control unit. The minimum temperature is -30°C and the maximum temperature is 40°C; the maximum treatment duration is 300 seconds.
The user interface is the means by which the user can view system status and state of each operational mode. The software provides three primary functions: allowing the user to select a treatment plan; establishing communications with the TEC controller and monitoring and displaying treatment progress.
Use of a TEC with closed-loop temperature feedback for cooling, as provided by the Dermal Cooling System, allows the selected temperature to be precisely and accurately maintained throughout the treatment. The TEC controller in the control unit communicates to the TEC module in the handpiece, maintaining the temperature defined in the treatment plan selected by the user. As heat is removed from the skin through contact with the aluminum plate, it is then transferred through the TEC module to the heat exchanger, which is fluid cooled. The chiller maintains a continuous flow of coolant which is circulated through the heat exchanger to carry heat way from the TEC module. The Dermal Cooling System generates sufficient thermal power to cool the aluminum contact plate to a pre-set temperature over a pre-set time. The temperature of the cooling surface, as measured by the thermistor affixed to the aluminum contact plate, is fed into the TEC controller which modulates power to the TEC such that the surface temperatures are precisely controlled. The Dermal Cooling System has an automatic shut-off feature if the temperature for the TEC and cooling plate are out of range.
The Dermal Cooling System operates from standard 120 VAC (60 Hz) power to provide controlled, active cooling at the skin interface throughout the procedure.
Here's an analysis of the provided text regarding acceptance criteria and the study:
The document describes the Dermal Cooling System, a cryosurgical instrument. The information provided focuses on the substantial equivalence determination for an expanded indication, rather than a detailed study proving the device meets acceptance criteria in a traditional sense for a novel device's performance. Instead, it demonstrates that the device already meets performance necessary for the expanded indication by comparing it to predicate devices and inherent capabilities.
Here's a breakdown of the requested information based on the provided text:
1. A table of acceptance criteria and the reported device performance
| Test | Test method/Requirement | Acceptance criteria | Reported Device Performance |
|---|---|---|---|
| System Validation | System performance when subjected to varied contours and body geometries | System is able to cool skin's surface to between +2°C and +4°C and maintain temperature for 10 minutes | Passed |
| System Validation | System performance when subjected to varied contours and body geometries | Handpiece does not stick to tissue and no visible blanching | Passed |
2. Sample size used for the test set and the data provenance
The document does not specify a distinct "test set" with a particular sample size for the System Validation tests. The evaluation appears to be based on bench testing of the device itself rather than a study involving a cohort of subjects. Therefore, information on data provenance (country of origin, retrospective/prospective) is not applicable in the context of human subject testing.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
Not applicable. The ground truth for the "System Validation" tests was established through direct measurement and observation of the device's physical performance (temperature, sticking, blanching) during bench testing, not through expert interpretation of data.
4. Adjudication method for the test set
Not applicable, as the evaluation was based on direct physical measurements and observations during bench testing, not subjective interpretation requiring adjudication.
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
Not applicable. This device is a physical cryosurgical instrument, not an AI-powered diagnostic or assistive tool for human readers. Therefore, an MRMC study is not relevant to its evaluation.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This is a physical medical device, not an algorithm. Its "standalone" performance is its direct operational capability, as assessed by the bench tests.
7. The type of ground truth used
For the "System Validation" tests, the ground truth was based on direct physical measurements and observations of the device's temperature control capabilities and interaction with simulated tissue (implied by "varied contours and body geometries" and "handpiece does not stick to tissue and no visible blanching"). This is a form of engineering/performance validation rather than a clinical ground truth like pathology or outcomes data.
8. The sample size for the training set
Not applicable. The document does not describe the development of a machine learning model or algorithm that would require a training set. The device's operation is based on established engineering principles (thermoelectric cooling with closed-loop temperature feedback).
9. How the ground truth for the training set was established
Not applicable, as there is no training set for a machine learning model described.
§ 878.4350 Cryosurgical unit and accessories.
(a)
Identification —(1)Cryosurgical unit with a liquid nitrogen cooled cryoprobe and accessories. A cryosurgical unit with a liquid nitrogen cooled cryoprobe and accessories is a device intended to destroy tissue during surgical procedures by applying extreme cold.(2)
Cryosurgical unit with a nitrous oxide cooled cryoprobe and accessories. A cryosurgical unit with a nitrous oxide cooled cryoprobe and accessories is a device intended to destroy tissue during surgical procedures, including urological applications, by applying extreme cold.(3)
Cryosurgical unit with a carbon dioxide cooled cryoprobe or a carbon dioxide dry ice applicator and accessories. A cryosurgical unit with a carbon dioxide cooled cryoprobe or a carbon dioxide dry ice applicator and accessories is a device intended to destroy tissue during surgical procedures by applying extreme cold. The device is intended to treat disease conditions such as tumors, skin cancers, acne scars, or hemangiomas (benign tumors consisting of newly formed blood vessels) and various benign or malignant gynecological conditions affecting vulvar, vaginal, or cervical tissue. The device is not intended for urological applications.(b)
Classification. Class II.