(90 days)
These low temperature thermoplastic sheets may be used to fabricate custom positioning and immobilization devices for radiation therapy. These sheets may be formed directly against the patient's skin to produce immobilizer for any part of the body. The immobilizer should be used any time precise, repeatable positioning of a patient is required.
This device consists of a thermoplastic material which is intended to be used in a handling frame by radiotherapists in fabricating custom supports, positioning and immobilization devices for the head, neck, breast, neck and chest and foot, and other parts of the body. The device in its application consists of a conforming net of rigid thermoplastic material effecting immobilization. This thermoplastic material is intended for the fabrication of custom supports, positioning and immobilizing devices for use in radiotherapy.
The Rehabilitation Division, Smith & Nephew, Inc. thermoplastic material for the radiotherapy positioning application will consist of Radio-plast material in 1/16 inch (1.6mm), 3/32 inch (2.4mm) and 1/8 inch (3.2 mm) thicknesses, in various perforation patterns, with perforation percentages of 42%. Radio-plast will be marketed for both in sheets and in precut shapes to fit various frames designed by MED-TEC, Inc. and other suppliers currently on the market.
The provided 510(k) summary for K981115 describes a thermoplastic material for radiotherapy positioning. This submission focuses on demonstrating substantial equivalence to an existing legally marketed device (Aquaplast), rather than providing detailed performance data from a clinical study with acceptance criteria.
Therefore, much of the requested information regarding acceptance criteria, specific test sets, expert consensus, and multi-reader multi-case studies is not applicable to this type of submission. The provided document details biocompatibility testing as its primary method of demonstrating equivalence.
Here's a breakdown of the available information based on your request:
Acceptance Criteria and Reported Device Performance
| Acceptance Criteria | Reported Device Performance (Radio-plast / Aquaplast) |
|---|---|
| Biocompatibility - Cytotoxicity (Elution Test): Meets requirements of USP 23 and ISO 10993-5 | Exhibited mild reactivity |
| Biocompatibility - Cytotoxicity (Agar Diffusion Test): Meets requirements of USP 23 and ISO 10993-5 | Exhibited slight reactivity |
| Biocompatibility - FHSA Primary Dermal Irritation: Non-irritating to skin | Found to be non-irritating to the skin of New Zealand rabbits |
| Biocompatibility - Dermal Sensitization: Weak potential for sensitization | Found to have a weak potential for sensitization |
| Immobilizing Characteristics: Substantially equivalent to Aquaplast | Consists of the same material under different proprietary names; shown to be substantially equivalent. |
| Radiation Attenuation: Equivalent to 1.5 times its thickness of water | Approximately equivalent to 1.5 times its thickness of water (determined using a teletherapy type cobalt 60 beam) |
Study Details
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Sample size used for the test set and the data provenance:
- The document does not specify a "test set" in the context of clinical images or patient data.
- For biocompatibility testing, New Zealand rabbits were used for the FHSA Primary Dermal Irritation and Dermal Sensitization tests. The sample size for these animal tests is not explicitly stated.
- The data provenance for the biocompatibility tests is presumably from internal lab testing or contracted testing. Country of origin is not specified. The studies are implicitly prospective for the specific tests performed.
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable. This device is a material, not an AI or diagnostic imaging device that requires expert ground truth for interpretation of medical images. The "ground truth" for biocompatibility is established by the test methods themselves and established biological responses.
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Adjudication method (e.g. 2+1, 3+1, none) for the test set:
- Not applicable. This is not a study involving human interpretation of data requiring adjudication.
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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 is not an AI-assisted device.
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If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- Not applicable. This is a physical material, not an algorithm. However, the biocompatibility tests and radiation attenuation measurements are standalone evaluations of the material's properties.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc):
- For biocompatibility: Ground truth is established by the specified standards (USP 23, ISO 10993-5) and standardized animal testing protocols (e.g., FHSA, Magnusson, Kligman Maximization Test).
- For immobilizing characteristics and radiation attenuation: The ground truth is based on physical and material science measurements compared to the predicate device.
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The sample size for the training set:
- Not applicable. No "training set" in the context of machine learning or AI is relevant here.
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How the ground truth for the training set was established:
- Not applicable. See point 7.
§ 892.5050 Medical charged-particle radiation therapy system.
(a)
Identification. A medical charged-particle radiation therapy system is a device that produces by acceleration high energy charged particles (e.g., electrons and protons) intended for use in radiation therapy. This generic type of device may include signal analysis and display equipment, patient and equipment supports, treatment planning computer programs, component parts, and accessories.(b)
Classification. Class II. When intended for use as a quality control system, the film dosimetry system (film scanning system) included as an accessory to the device described in paragraph (a) of this section, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.