The HI STAR system is indicated for use a general purpose MR imager that produces transverse, sagittal, coronal, and oblique cross-sectional images of internal structures of the human body, head, and extremities. Contrast in these images reflect the intrinsic oroperties of the hydrogen proton, proton density, T1, and T2, and the extrinsic parameters of the applied imaging sequences. The indications for the HI STAR do not differ significantly from the predicate, or legally marketed devices.

Device Description

The Health Images HI STAR is a proton (H-1) Magnetic Resonance Imaging device. The HI STAR has been designed to produce transverse, sagittal, coronal, and oblique section images of the head, body and extremities of the human body. Contrast in these images is produced primarily by T1, T2, and proton density tissue characteristics. This imager employs conventional MRI imaging techniques in which the application of a combination of pulsed radio frequency energy and magnetic gradient fields is applied to the body to generate MR proton echo signals. These multidimensionally coded signals are converted by Fourier transform into 2D and 3D image sets.

AI/ML Overview

Here's an analysis of the provided text regarding acceptance criteria and the study that proves the device meets those criteria:

It's important to note that this document is a 510(k) Summary from 1997, specifically for a Magnetic Resonance Imager (MRI). The nature of acceptance criteria and supporting studies for such a device at that time, and compared to a more modern AI/software-as-a-medical-device (SaMD) submission, will be different. This document focuses on hardware performance and safety rather than diagnostic accuracy of an AI algorithm.

1. A table of acceptance criteria and the reported device performance

The document provides "Safety Parameters" and "Imaging Performance Parameters" which function as acceptance criteria for the MRI device.

Parameter Criterion	Acceptance Criteria (FDA Limit/Standard)	Reported Device Performance (HI STAR)
Safety Parameters
Maximum Static Magnetic Field	≤ 2 tesla	0.6T
Rate of Magnetic Field Strength change	≤ 20 T/second	< 20 T/s
SAR (whole body, First Controlled)	< 1.5 W/kg, averaged over whole body	< 1.5 W/kg
SAR (whole body, Second Controlled)	1.5 ≤ SAR < 4.0 W/kg, averaged over whole body	1.5 ≤ SAR < 4.0 W/kg
Acoustic Noise Levels	< 105 dB (A weighted average over 1 hour)	< 92 dBA
Imaging Performance Parameters	Standard	Data (HI STAR)
Specification Volume (Head)	Manufacture	25.6 cm DSV
Specification Volume (Body)	Manufacture	48 cm DSV
Signal-to-noise Ratio (Body Coil)	NEMA MS-1	103
Signal-to-noise Ratio (Head Coil)	NEMA MS-1	62
Signal-to-noise Ratio (MRA Coil)	NEMA MS-6	50
Signal-to-noise Ratio (Wrist Coil)	NEMA MS-6	117
Signal-to-noise Ratio (Neck Coil)	NEMA MS-6	108
Signal-to-noise Ratio (Spine Coil)	NEMA MS-6	62
Signal-to-noise Ratio (Breast Coil)	NEMA MS-6	100
Signal-to-noise Ratio (Bilateral TMJ)	NEMA MS-6	133
Signal-to-noise Ratio (Extremity Coil)	NEMA MS-6	49
Signal-to-noise Ratio (Shoulder Coil)	NEMA MS-6	108
Signal-to-noise Ratio (GPS Coils)	NEMA MS-6	95 (29.2x15.2cm), 98 (19x19cm), 80 (12.7x12.7cm), 133 (6.4x6.4cm)
Image Uniformity (Body Coil)	NEMA MS-2	12%, Specification Volume 48 cm
Image Uniformity (Head Coil)	NEMA MS-2	6%, Specification Volume 25.6 cm
Slice Thickness, Separation	AAPM-28	10% of specified
Resolution (Body)	AAPM-28	1.5 mm
Resolution (Head)	AAPM-28	1 mm
Geometric Distortion (Body)	NEMA #2	< 5% @ 31 cm
Geometric Distortion (Head)	NEMA #2	< 5% @ 15.5 cm

2. Sample size used for the test set and the data provenance

The document states: "Sample images included with this submission were obtained on R &D systems at Health Sample Includio war this oubmisers. Each volunteer signed a consent form. There were no adverse reactions noted on any of the participants."

Sample Size: The exact number of "volunteers" is not specified. It refers to "sample images" and "each volunteer," implying a limited, unnamed number.
Data Provenance: The images were obtained on R&D systems at Health Images itself. It was collected from "volunteers" who signed consent forms, suggesting these were healthy volunteers rather than patients with specific pathologies. The study appears to be prospective in nature, as images were "obtained" for the submission, rather than retrospective analysis of existing data. The country of origin is implicitly the United States, given the submitter's address and FDA context.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts

This information is not provided in the document. For an MRI device submission of this nature (hardware performance), the "ground truth" for imaging parameters (SNR, uniformity, resolution, distortion) is typically established through quantitative measurements using phantoms and standardized protocols (e.g., NEMA standards), not expert interpretation of clinical images. The safety parameters are also measured quantitatively against established limits.

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

This is not applicable and therefore not provided. Adjudication methods are relevant for studies requiring multiple expert interpretations to establish a consensus ground truth for diagnostic AI, which is not the type of study described here.

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

This is not applicable and therefore not provided. This document pertains to the performance of an MRI machine itself, not an AI-assisted diagnostic tool. There is no mention of human readers or AI assistance in the context of diagnostic interpretation.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

This is not applicable and therefore not provided. This document is for an MRI hardware device, not a standalone AI algorithm.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

The "ground truth" for the performance metrics appears to be based on:

Physical measurements against industry standards/specifications: For imaging parameters like SNR, image uniformity, slice thickness, resolution, and geometric distortion, the device's performance is compared against NEMA and AAPM standards. These involve quantitative measurements using phantoms, not clinical ground truth like pathology or expert consensus.
Quantitative measurements against regulatory limits: For safety parameters such as magnetic field strength, SAR, and acoustic noise, physical measurements are taken and compared directly to FDA limits and IEC standards.

8. The sample size for the training set

This is not applicable and therefore not provided. This document describes an MRI hardware device, not a machine learning model that requires a training set.

9. How the ground truth for the training set was established

This is not applicable and therefore not provided. As there is no training set for an AI algorithm mentioned, there is no ground truth established for one.

Summary

{0}------------------------------------------------

K964778

FEB 2 4 1997

Attachment H

510 (k) Summary / Safety and Effectiveness

510 (k) Summary, Safety and Effectiveness

{1}------------------------------------------------

The following information is in accordance with 21 CFR 807.92

Submitter's Name, Address, Telephone Number , Contact Person, Preparation Date

Health Images, Inc. 8601 Dunwoody Place Building 200 Atlanta, GA 30350 (770) 642-9869 ext. 2057 Richard Halbach, Dir. of Clinical Research & Regulatory Affairs

November 25, 1996

Name of the Device and Classification Name/Number

HI STAR, Magnetic Resonance Imager. The FDA has reclassified these devices, 90LNH, to Class II.

Predicate Devices

Manufacturer	Commercial Name	Description
Health Images	HI-Standard	0.6T whole body MRI imager,superconducting magnet
Health Images	HI-Standard/CalibreIRIS sequence	0.6T whole body MRI imager,superconducting magnet, IRISSilicone Specific Sequence
Health Images	HI STAR	0.6T whole body MRI imager,superconducting magnet
Elscint	Gyrex 2T Prestige	Spectral Fat Suppression, FSE
Philips	Gyroscan NT, 1T	Spectral Fat Suppression

Description of the Device

{2}------------------------------------------------

194466

Device Characteristics

Parameter	Example
Type of magnet	Superconducting,passive/active shim
Static field strength	0.6T
Type of RF coils	Transmit/Receive - quadratureBody
	Receive - quadratureHead, MRA, Neck,Spine, WristReceive - linearBilateral TMJ, VolumeExtremity, Bilateral Breast,ShoulderGeneral Purpose Surface(body & extremity)29.2 cm x 15.2 cm(11.5 x 6.0 inch)19.0 cm x 19.0 cm(7.5 x 7.5 inch)12.7 cm x 12.7 cm(5.0 x 5.0 inch)6.4 cm x 6.4 cm(2.5 x 2.5 inch)
Data acquisition modes	Single slice, Multi-slice, Multi-angle oblique, 3D Volume,Physiologic Gating
Pulse Sequences	Spin Echo, Field Echo, TurboField Echo, Multi-spin Echo,Inversion Recovery, MRA, FSE
Additional Contrast Techniques	IRIS (Silicone Specific), FatSat,Magnetization Transfer
Reconstruction Technique	Fourier transform
Type of installation:	Mobile, Fixed
Slice selection method:	Selective Gradient,3D phase encode
Display Matrix	Variable up to 1024 x 1024

{3}------------------------------------------------

In plane 64 - 512, increment of Acquisition Matrix 8 2D, 1 - 256 slices, increment of Number of slices, 1 3D, 12 - 256 increment of 2 Range and Increment Window and level Post processing Rotate image Mirror image Zoom image Pan image Add and Subtract images HI-Q image processing noise reduction function Transverse, Sagittal, Coronal, Slice orientation Single and multiple oblique From Contiguous up to 320 mm, Interslice spacing, minimum, maximum, increment of 0.5 mm

....

{4}------------------------------------------------

Intended Uses

Safety Parameters

Parameter	FDA Limit	HI STAR	Test Standard
Maximum Static MagneticField	≤ 2 tesla	0.6T	Manufacturer
Rate of Magnetic FieldStrength change	≤ 20 T/second	< 20 T/s	IEC 601-2-33
SAR	< 1.5 W/kg, averaged overwhole body (First ControlledOperating Level)	< 1.5 W/kg	IEC 601-2-33
	1.5 ≤ SAR < 4.0 W/kg,averaged over wholebody (Second ControlledOperating Level)	1.5 ≤ SAR < 4.0W/kg	IEC 601-2-33
Acoustic Noise Levels	< 105 dB (A weighted averageover 1 hour)	< 92 dBA	NEMA MS-4

Imaging Performance Parameters

Parameter	Data	Standard
Specification Volume	Head 25.6 cm DSVBody 48 cm DSV	Manufacture
Signal-to-noise Ratio
Body Coil	103	NEMA MS-1
Head Coil	62	NEMA MS-1
MRA Coil	50	NEMA MS-6
Wrist Coil	117	NEMA MS-6
Neck Coil	108	NEMA MS-6
Spine Coil	62	NEMA MS-6
Breast Coil	100	NEMA MS-6
Bilateral TMJ Coil	133	NEMA MS-6
Extremity Coil	49	NEMA MS-6
Shoulder Coil	108	NEMA MS-6

{5}------------------------------------------------

Parameter	Data	Standard
General PurposeSurface Coils29.2 cm x 15.2 cm(11.5 x 6.0 inch)19.0 cm x 19.0 cm(7.5 x 7.5 inch)12.7 cm x 12.7 cm(5.0 x 5.0 inch)6.4 cm x 6.4 cm(2.5 x 2.5 inch)	959880133	NEMA MS-6
Image Uniformity
Body Coil	12%, Specification Volume 48 cm	NEMA MS-2
Head Coil	6%, Specification Volume 25.6 cm	NEMA MS-2
Slice Thickness, Separation	10% of specified	AAPM-28
Resolution	Body 1.5 mmHead 1 mm	AAPM-28
Geometric Distortion	Body < 5% @ 31 cmHead < 5% @ 15.5 cm	NEMA #2

Sample images included with this submission were obtained on R &D systems at Health Sample Includio war this oubmisers. Each volunteer signed a consent form. There were no adverse reactions noted on any of the participants.

Regulation Number and Section

§ 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.