Imaging of the whole body (including the head, abdomen, heart, pelvis, spine, blood vessels, limbs and extremities), fluid visualization, 2D/3D Imaging, MR Angiography, MR. Fluoroscopy

Device Description

The VISART™ consists of two model upgrades to the MRT-150A system which provide increased gradient field strength, more ergonomic computer architecture, improved scan parameter specifications and a lighter magnet than the MRT-150A.

AI/ML Overview

This is a pre-amendment 510(k) submission for the VISART™ Magnetic Resonance Device, MRT-150A/H1 and MRT-150A/F1 models. The submission primarily focuses on demonstrating substantial equivalence to an existing device (MRT-150A) by highlighting hardware and software upgrades that improve performance without introducing new safety or effectiveness questions. The provided text, however, does not contain details about a specific study testing device performance against defined acceptance criteria in the manner typically seen for algorithmic or AI-based devices.

The submission describes general increases in imaging performance parameters and safety parameters compared to the predicate device. It also mentions that "Sample phantom images and clinical images were presented for all new sequences demonstrating conformance with consensus standards requirements for Signal-to-Noise ratio Uniformity, Slice Profiles, Geometric Distortion and Slice Thickness/Interslice Spacing." This indicates that some form of evaluation was performed, but the specifics of a structured study with statistical outcomes are not detailed.

Given the information provided, I cannot fully answer your request in the format you've outlined for an AI/algorithm-driven device's acceptance criteria and study. However, I can extract the relevant information as much as possible based on the provided text.

Here's an attempt to address your request based on the available information:

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't explicitly state "acceptance criteria" for the upgraded models in a quantitative, pass/fail manner. Instead, it highlights improvements over the predicate device (MRT-150A) and states conformance with "consensus standards requirements."

Parameter	Acceptance Criteria (Implied / Stated Conformance)	Reported Device Performance (MRT-150A/H1 & MRT-150A/F1)
Safety Parameters
Max. Static Field Strength	Not explicitly stated, but "Same" as predicate (1.5T) is presented as acceptable.	1.5T (Same as MRT-150A)
Rate of Change of Magnetic Field ($\tau$=1000ms)	Not explicitly stated, but an improved rate is presented as acceptable and less than IEC standard.	13.3 T/sec. (Improved from 7.5 T/sec. of MRT-150A)
Max. Radio Frequency Power Deposition	Not explicitly stated, but an improved/reduced value is presented as acceptable.	<0.4 W/kg (Improved from <1.0 W/kg of MRT-150A)
Acoustic Noise Levels	NEMA guidelines conformance. User is cautioned to have patient wear acoustic noise protection.	105.3 dB (Maximum for MRT-150A/H1), 103.9 dB (Maximum for MRT-150A/F1). Measured in accordance with NEMA guidelines.
Imaging Performance
Head Specification Volume	Improved from predicate (10 cm dsv)	16cm dsv (Improved from 10 cm dsv of MRT-150A)
Body Specification Volume	Improved from predicate (20 cm dsv)	28cm dsv (Improved from 20 cm dsv of MRT-150A)
Image Quality (SNR, Uniformity, Slice Profiles, Geometric Distortion, Slice Thickness/Interslice Spacing)	Conformance with consensus standards requirements.	"Sample phantom images and clinical images were presented for all new sequences demonstrating conformance with consensus standards requirements."

2. Sample Size Used for the Test Set and Data Provenance

The document states: "Sample phantom images and clinical images were presented for all new sequences."

Sample Size: Not specified. The term "sample" implies a subset, but no numbers are given.
Data Provenance: Not specified. Given the manufacturing site is in Japan, the clinical images could be from Japan, but this is not stated. It is also not specified if the data was retrospective or prospective.

3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of those Experts

This information is not provided in the summary. The document mentions "consensus standards requirements" for image quality, suggesting that expert review or adherence to established scientific norms formed the basis of evaluation, but details on individual experts are absent.

4. Adjudication Method for the Test Set

This information is not provided in the summary.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done

No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done or at least not reported in this summary. The submission focuses on hardware and software upgrades and their performance characteristics, not on human reader performance with or without AI assistance.

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

This submission pertains to an MRI device, not an AI algorithm. Therefore, the concept of a "standalone algorithm" performance as typically understood for AI devices does not apply here. The performance evaluation was for the imaging system itself.

7. The Type of Ground Truth Used

For image quality parameters (SNR, Uniformity, Slice Profiles, Geometric Distortion, Slice Thickness/Interslice Spacing), the ground truth was implicitly based on:

Phantom images: Objective measurements against known phantom properties.
Clinical images: Presumably evaluated by experts against established diagnostic criteria or visual inspection for quality, demonstrating "conformance with consensus standards requirements." The exact nature of this "ground truth" (e.g., pathology, outcomes data) for clinical images is not specified.

8. The Sample Size for the Training Set

This information is not applicable as the document describes an MR imaging device and its upgrades, not the development of a machine learning algorithm with a training set.

9. How the Ground Truth for the Training Set was Established

This information is not applicable for the same reason as above.

Summary

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

K961092

JUN 1 4 1996

510(k) Summary

SUMMARY OF SAFETY AND EFFECTIVENESS

MRT-150A/H1 and MRT-150A/F1 Model Name: 1. Magnetic Resonance Device Device Name: VISARTTM Trade/Proprietary Name:
1. Establishment Registration: #2020563

1 11 11 16 11

TOSHIBA AMERICA MEDICAL SYSTEMS, INC. U.S. Agent Name and Address: 3. 2441 Michelle Drive P.O. Box 2068 Tustin, CA 92681-2068

Contact Person: Steven M. Kay (714) 730-5000

Toshiba Corporation Manufacturing Site: 4. 1385 Shimoishigami Otawara-shi, Tochigi-Ken Japan 324

5. DATE OF SUBMISSION: March ? 1996

DEVICE DESCRIPTION 6.

7. SAFETY PARAMETERS

	MRT-150A	MRT-150/H1	MRT-150/F1
Maximum static field strength:	1.5T	Same	Same
Rate of change of magnetic field ( $\tau$ = 1000ms):	7.5T/sec,	13.3T/sec.	13.3T/sec.
Max. Radio frequency power deposition:	<1.0W/kg	<0.4W/kg	<0.4W/kg
Acoustic Noise levels:	85 - 100 dB(Typical)	105.3 dB(Maximum)	103.9 dB(Maximum)

Acoustic noise data was measured in accordance with NEMA guidelines. The user is cautioned to have the patient wear acoustic noise protection during scanning.

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

510(k) Summary (cont'd)

SUMMARY OF SAFETY AND EFFECTIVENESS

IMAGING PERFORMANCE PARAMETERS 8.

Specification volume:	MRT-150A	MRT-150/H1	MRT-150/WF1
Head:	10 cm dsv	16cm dsv	16cm dsv
Body:	20 cm dsv	28cm dsv	28cm dsv
Sample phantom images and clinical images were presented for all new sequences demonstrating conformance with consensus standards requirements for Signal-to-Noise ratio Uniformity, Slice Profiles, Geometric Distortion and Slice Thickness/Interslice Spacing.

INTENDED USE 9.

Anatomical Region:	Head, Body, Extremity, Spine, Neck, TMJ, and Heart
Nuclei excited:	Hydrogen
Diagnostic Use:	Imaging of the whole body (including the head, abdomen, heart, pelvis, spine, blood vessels, limbs and extremities), fluid visualization, 2D/3D Imaging, MR Angiography, MR. Fluoroscopy

10. EQUIVALENCY INFORMATION

Toshiba America Medical Systems, Inc. (TAMS) believes the VISART™ is substantially equivalent to the MRT-150A because it consists of hardware and software upgrades that improve the performance of the MRT-150A, without introducing new questions of safety or The MRT-150A was cleared by K903768A. The improved computer system efficacy. architecture and user interface were cleared with the Flexart™ via K933018. The increased gradient field strength is less than the IEC standard and that of other manufacturers systems currently on the market. New surface coils for this system received prior market clearance from the Agency. The new magnet offers siting and shipping advantages, but does not change the system's performance characteristics. Software upgrades provide for improved image quality, but do not change the intended uses of the device. MR Fluoroscopy is similar to the same function that was cleared for the MRT-35A. Good Manufacturing Practices requirements are unchanged from those already in effect for the MRT-150A.

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.