(71 days)
The Hammersmith Endocavitary Coils do not change the intended use of the Picker MR system with which they are used.
Picker MR systems are intended for use as NMR devices that produce images that: (1) correspond to the distribution of protons exhibiting NMR, (2) devend upon NMR parameters (proton density, flow velocity, spin-lattice relaxation time T1, spin-spin relaxation time T2) and (3) display the soft tissue structure of the head and whole body. When interpreted by a trained physician, these images vield information that can be useful in the determination of a diagnosis.
The Hammersmith Endocavitary Coils are indicated for use in the following anatomic regions and with the designated nuclei:
Anatomic Regions: The Anus or Prostate by insertion into the rectum, and the Cervix by insertion into the vagina Nuclei Excited: Hydrogen
These three separate receive-only coils are for imaging the anus, prostate and cervix. The coils are designed to be inserted in either the rectum or vagina before imaging. The Hammersmith Endocavitary Coils are similar to the Philips Endo-Cavitary Coil in that they are reusable. However, unlike the Philips Endo-cavitary MRI Coil, they are rigid structures that do not contain an inflatable latex balloon. This difference in the design eliminates the need for limiting the number of times the Hammersmith Coils can be used, allows for fixed tuning and matching, and reduces the image artifacts due to susceptibility effects from air. Instead, the shape and dimensions of the Hammersmith Endocavitary Coils are similar to ultrasound probes used in endocavitary applications.
This document is a 510(k) premarket notification for a medical device called "Hammersmith Endocavitary Coils." It does not describe a study to prove acceptance criteria in the way an AI/ML device submission would. This submission focuses on demonstrating substantial equivalence to a predicate device, which is a different regulatory pathway.
Therefore, many of the requested categories for AI/ML device studies are not applicable or cannot be extracted from this document, as it predates modern AI/ML medical device regulations and practices.
Here's a breakdown of what can be extracted and what cannot:
1. A table of acceptance criteria and the reported device performance
This document does not present acceptance criteria in the typical format of a performance study with quantitative metrics and thresholds. Instead, it demonstrates "substantial equivalence" based on various design and operational parameters compared to a predicate device.
| Parameter | Hammersmith Endocavitary Coils | Predicate Device: Philips Endo-Cavitary MRI Coil (K930193) |
|---|---|---|
| Compatible MRI Systems | Picker Edge, Vista, Asset, Eclipse, Polaris and Apollo. | Philips Gyroscan ACS Series II and Gyroscan T5 series II systems. |
| Mode of Operation | Receive-Only. | Receive-Only. |
| Antenna Configuration | Linear. | Linear. |
| Tuning/Impedance Matching | Fixed tuning and matching. Factory set. | Tuned for each patient. |
| Method of Decoupling | Active diode decoupling. | Decoupling diode switch |
| Coil Enclosure | Rigid Acrylonitrile resin. | Flexible coil loop inside a non-permeable latex balloon. |
| Coil Stabilization | External immobilization positioning device. | Inflate balloon on coil with luer-lock syringe. |
| Number of Receive Channels | One. | One. |
| Cleaning and Disinfection Method | Cleaning: MetriZyme detergent. Disinfectant: Cidex Dip. Covered with sheath. | Cleaning: Detergent. Disinfectant: Cidex Dip. Covered with sheath. |
| Use Limits | None. | Used up to 50 times within one year of manufacturing. |
| Indications for use | Anus or Prostate by insertion into the rectum and Cervix by insertion into the vagina. | Prostate or Uterus by insertion into the rectum. |
| Contraindications | Any exclusion for a normal digital examination. | Severe hemorrhoids, recent surgery in the area of the rectum, inflammatory bowel disease, Crohn's disease and any exclusion for normal endorectal examinations. |
Regarding "reported device performance": The document doesn't provide specific numerical performance metrics (e.g., signal-to-noise ratio, spatial resolution values) but rather asserts that the coil does not change the intended use of the Picker MR system and yields information that can be useful in the determination of a diagnosis when interpreted by a trained physician. The performance is implicitly "substantially equivalent" to the predicate device.
2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
This document does not describe a clinical study with a "test set" in the context of an AI/ML device. The "proof" of meeting acceptance criteria is through the substantial equivalence comparison to a legally marketed predicate device, not a performance study on a specific dataset.
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)
Not applicable. No "ground truth" establishment in the context of an AI/ML device evaluation is described. The device is a hardware component (an MRI coil).
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable. No test set or adjudication process is described.
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 is not an AI-assisted device.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This is a hardware device (MRI coil), not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
Not applicable. No "ground truth" in the AI/ML sense is mentioned. The device's safety and effectiveness are established through demonstrating substantial equivalence to a predicate device.
8. The sample size for the training set
Not applicable. No training set is involved as this is a hardware device, not an AI/ML algorithm.
9. How the ground truth for the training set was established
Not applicable. No training set or ground truth establishment is described.
§ 892.1000 Magnetic resonance diagnostic device.
(a)
Identification. A magnetic resonance diagnostic device is intended for general diagnostic use to present images which reflect the spatial distribution and/or magnetic resonance spectra which reflect frequency and distribution of nuclei exhibiting nuclear magnetic resonance. Other physical parameters derived from the images and/or spectra may also be produced. The device includes hydrogen-1 (proton) imaging, sodium-23 imaging, hydrogen-1 spectroscopy, phosphorus-31 spectroscopy, and chemical shift imaging (preserving simultaneous frequency and spatial information).(b)
Classification. Class II (special controls). A magnetic resonance imaging disposable kit intended for use with a magnetic resonance diagnostic device only is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 892.9.