MRT-35A V9.0

K964608 · Toshiba America Mri, Inc. · LNH · Feb 4, 1997 · Radiology

Device Facts

• Record ID: K964608
• Device Name: MRT-35A V9.0
• Applicant: Toshiba America Mri, Inc.
• Product Code: LNH · Radiology
• Decision Date: Feb 4, 1997
• Decision: SESE
• Submission Type: Traditional
• Regulation: 21 CFR 892.1000
• Device Class: Class 2

Intended Use

1. Anatomical region: Head, Body, Spine, Neck, TMJ, and Heart 2. Nuclei excited: Hydrogen 3. Diagnostic Uses: 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 Story

MRT-35A v9.0 is an incremental hardware and software upgrade to the existing MRT-35A 0.35T superconducting MRI system. The upgrade replaces the version 8 computer system with architecture and user software derived from the Flexart™ and Visart™ systems. The device utilizes a 0.35T static magnetic field to excite hydrogen nuclei for diagnostic imaging. It performs 2D/3D imaging, MR angiography, and MR fluoroscopy. The system is operated by trained clinical staff in a radiology environment. Output consists of diagnostic images used by physicians to visualize anatomical structures and pathologies. The upgrade maintains existing magnet, gradient system, and coil set specifications, ensuring continuity in clinical diagnostic capabilities while updating the processing platform.

Clinical Evidence

Bench testing only. Performance validated using sample phantom images and clinical images for all new sequences. Conformance demonstrated for Signal-to-Noise ratio, Uniformity, Slice Profiles, Geometric Distortion, and Slice Thickness/Interslice Spacing.

Technological Characteristics

0.35T superconducting magnet MRI system. Upgrade replaces computer architecture and user console electronics. Operates via hydrogen nuclei excitation. Static field strength 0.35T; rate of change 6.83 T/sec; RF power deposition 0.3 W/kg. Software architecture based on Flexart™ system. No changes to gradient system or coil sets.

Indications for Use

Indicated for whole-body diagnostic magnetic resonance imaging, including head, abdomen, heart, pelvis, spine, blood vessels, limbs, and extremities, utilizing hydrogen nuclei excitation for fluid visualization, 2D/3D imaging, MR angiography, and MR fluoroscopy.

Regulatory Classification

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).

Special Controls

*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.

Predicate Devices

• MRT-35A with Version 8.0 series upgrade (K945798, K961842)
• Flexart™ (K933018, K962138)

Reference Devices

• Visart™

Submission Summary (Full Text)

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K964608

510(k) Summary

FEB - 4 1997

1. DEVICE NAME: Magnetic Resonance Device Accessory
Model Number: MRT-35A v9.0
Trade/Propriety Name: MRT-35A v9.0

2. ESTABLISHMENT REGISTRATION: 2936923

3. U.S. Agent Name and Address: Toshiba America MRI, Inc.
280 Utah Avenue
South San Francisco, California 94080

Contact Person: Steven M. Kay
[phone]

4. Manufacturing Site: Toshiba America MRI, Inc.
280 Utah Avenue
South San Francisco, California 94080

5. DATE OF SUBMISSION: November 15, 1996

6. DEVICE DESCRIPTION

The MRT-35A v9.0 is a modification of the MRT-35A system which uses a 0.35T superconducting magnet. The MRT-35A v9.0 is an incremental upgrade to an MRT-35A system which is configured with version 8 hardware and software. The 9.0 upgrade replaces the version 8 computer system. The computer architecture, operational characteristics and user software follow the same design considerations cleared by Flexart™ and Visart™ systems. This 9.0 upgrade makes no change to the MRT-35A version 8 series magnet, gradient system or coil set.

7. SAFETY PARAMETERS

| | MRT-35A
9.0 Upgrade | MRT-35A
8.0 Upgrade | Flexart™ |
| --- | --- | --- | --- |
| Maximum static field strength: | 0.35 T | same | 0.5 T |
| Rate of change of magnetic field: | 6.83 T/sec | same | 11 T/sec |
| Max. radio frequency power deposition: | 0.3 W/kg | 0.34 W/kg | <0.256 W/kg |
| Acoustic Noise levels: | 110.4 db
(max) | 101.6 db
(max) | 100.2 db
(max) |

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# 510(k) Summary (cont'd)

## 8. IMAGE PERFORMANCE PARAMETERS

| | | MRT-35A
9.0 Upgrade | MRT-35A
8.0 Upgrade | Flexart™ |
| --- | --- | --- | --- | --- |
| Specification Volume: | Head: | 10cm dsv | 10cm dsv | 10.4cm dsv |
| | Body: | 20cm dsv | 20cm dsv | 10.4cm 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.

## 9. INTENDED USE

1. Anatomical region: Head, Body, Spine, Neck, TMJ, and Heart
2. Nuclei excited: Hydrogen
3. Diagnostic Uses: 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. EQUIVALENCE INFORMATION

Toshiba America MRI, Inc. (TAMI) believes the MRT-35A v9.0 is substantially equivalent to the MRT-35A with Version 8.0 series upgrade and Flexart™ diagnostic magnetic resonance systems because it consists of hardware and software modifications that do not introduce new questions of safety or efficacy, nor does it introduce new indications for use. The MRT-35A Version 8 upgrade was cleared by K945798 and its latest software Version 8.5CD is described in K961842. The Flexart™ was cleared by K933018 and its latest software V3.1 is described in K962138. Operationally, the MRT-35A version 9.0 upgrade is based on the software technology of the Flexart™. The MRT-35A Version 9.0 Upgrade makes no change however, to the superconducting magnet, gradient coil, gradient power, MRT-35 coil set or patient couch from the prior MRT-35A upgrade: Version 8. The computer system, applications software, sequences and user console electronics compose is changed in the MRT-35 9.0 Upgrade and these components are based on those found in Flexart™. Manufacturing Practices requirements and software development procedures are unchanged from those already in effect for the Flexart™.