The MR system is an imaging device, and is intended to provide the physician with physiological and clinical information, obtained non-invasively and without the use of ionizing radiation. The MR system produces transverse, coronal, sagittal, oblique, and curved cross-sectional images that display the internal structure of the head, body, or extremities. The images produced by the MR system reflect the spatial distribution of protons (hydrogen nuclei) exhibiting magnetic resonance. The NMR properties that determine the image appearance are proton density, spin-lattice relaxation time (T1), spin-spin When interpreted by a trained physician, these images provide relaxation time (T2), and flow. information that can be useful in diagnosis determination.

Head, Body, Spine, Extremities Anatomical Region: Nucleus excited: Proton Diagnostic uses:
Diagnostic uses:

2D T1- / T2-weighted imaging T1. T2, proton density measurements MR Angiography image processing

Imaging capabilities:
2D, 3D Spin Echo (SE)
2D, 3D Fast Spin Echo (FSE)
2D Inversion Recovery (IR)
2D. 3D Fast Inversion Recovery (FIR)
2D,3D Gradient Echo (GE)
2D, 3D Steady state acquisition with rewinded GE (SARGE)
2D, 3D RF-spoiled SARGE (RSSG)
2D, 3D Time-reversed SARGE (TRSG)

MR Angiography (half echo, high resolution/high definition, sloped slab profile, magnetization transfer contrast)

2D, 3D TOF
2D, 3D TOF RSSG
ECG, Peripheral Gating
RF Coil Uniformity

Adaptive Image post-processing

ACR/NEMA/DICOM 3 compliant

Aids in the performance of minimally invasive, diagnostic, and therapeutic procedures of the head, body and extremities which may be facilitated by real-time MR guidance. Such procedures must be performed with MRI-compatible instrumentation, as selected and evaluated by the clinical user.

Device Description

The AIRIS and AIRIS II MRI Magnetic Resonance Diagnostic Devices are being enhanced by one additional RF Coil (PA/QD Shoulder Coil) to increase the clinical utility of the AIRIS and AIRIS II in the stationary configuration. The Shoulder Coil can operate either in the quadrature mode or in the phased array mode with the AIRIS II, and in the quadrature mode only with the AIRIS. The coil is available in Large and Standard sizes for both MRI systems, to accommodate a wide variety of physical patient sizes, and to achieve maximal coil filling factors.

AI/ML Overview

The provided document is a 510(k) Summary for a new RF Coil (PA/QD Shoulder Coil) for existing MRI systems (AIRIS and AIRIS II). This submission is for an enhancement to an already cleared device, primarily adding a new accessory. Therefore, the document does not contain a comprehensive clinical study with acceptance criteria and performance metrics in the way one would expect for a novel diagnostic algorithm or a new primary imaging modality.

Instead, the submission focuses on demonstrating substantial equivalence to the predicate device, meaning it asserts that the new coil performs similarly and introduces no new safety or effectiveness concerns. The "acceptance criteria" here are implicitly tied to the performance characteristics of the predicate MRI systems and the ability of the new coil to function within those established parameters.

Here's an attempt to answer your questions based on the provided text, acknowledging the limitations of a 510(k) for an accessory:

Acceptance Criteria and Device Performance Study for the PA/QD Shoulder Coil

As this 510(k) submission (K992650) is for an additional RF Coil (PA/QD Shoulder Coil) for existing, cleared MRI systems (Hitachi AIRIS and AIRIS II), the "acceptance criteria" and "study" described are focused on demonstrating that the new coil functions as intended within the established safety and performance envelope of the predicate devices. The submission emphasizes substantial equivalence to the predicate MRI systems and their existing coils, rather than a de novo clinical trial with specific diagnostic performance metrics.

The implicit acceptance criteria are that the new shoulder coil allows the AIRIS and AIRIS II systems to continue to produce high-quality diagnostic images of the shoulder joint, consistent with the performance of the predicate devices for other anatomical regions or with previous coils. The performance is "proven" through the assertion that the device's technological characteristics are identical to the predicate device in terms of fundamental MR physics and imaging capabilities, and that the new coil enhances clinical utility without altering the core functional mechanism or safety profile.

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

Acceptance Criteria Category	Description (Implicit)	Reported Device Performance (Implicit)
Image Quality & Functionality	The PA/QD Shoulder Coil, when used with AIRIS/AIRIS II, produces diagnostic quality images of the shoulder articular anatomy and other large joints, consistent with the intended use of the MR system. This implies sufficient signal-to-noise ratio, resolution, and artifact suppression for clinical diagnosis.	"The PA/QD Shoulder Coil provides imaging of the shoulder articular anatomy and other large joints." "The AIRIS and AIRIS II MRI Magnetic Resonance Diagnostic Devices are being enhanced by one additional RF Coil (PA/QD Shoulder Coil) to increase the clinical utility of the AIRIS and AIRIS II in the stationary configuration." The document implies that the coil functions as expected to deliver images with the same diagnostic capabilities and characteristics as the predicate system for the specified anatomical region.
Technological Equivalence	The fundamental scientific principles, physical and performance characteristics, imaging capabilities, and operation with MR systems are identical or substantially equivalent to the predicate MRI systems and their existing coils.	"DEVICE TECHNOLOGICAL CHARACTERISTICS: Identical to the Predicate Device." "AIRIS and AIRIS II software did not need to be revised in order to support full functionality of this PA/QD Shoulder Coil." This confirms that the new coil operates within the established technical framework. "MR system produces transverse, coronal, sagittal, oblique, and curved cross-sectional images that display the internal structure..."
Safety	The addition of the PA/QD Shoulder Coil does not introduce new safety concerns (e.g., related to SAR, heating, or magnetic field interactions) beyond those already characterized for the predicate MRI system.	While not explicitly stated as "safety results," the fact that the submission states "PRODUCT/TECHNOLOGICAL CHARACTERISTICS Identical to the Predicate Device." and received FDA clearance without specified safety concerns implies that safety was deemed equivalent to the predicate. RF Coil Uniformity is listed as an imaging capability, which contributes to image quality and implicitly to safe operation.
Intended Use	The coil performs within the defined intended uses for the AIRIS/AIRIS II MR system.	The "Indications for Use" section explicitly states: "The PA/QD Shoulder Coil provides imaging of the shoulder articular anatomy and other large joints." The overall intended use of the MR system ("to provide the physician with physiological and clinical information... useful in diagnosis determination") remains unchanged and is extended to the shoulder via this coil.

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

The document does not describe a specific clinical "test set" or a formal clinical study with patient data in the realm of diagnostic performance. For an accessory like an RF coil, "testing" would typically involve engineering verification and validation (e.g., phantom imaging, signal-to-noise measurements, image uniformity, SAR testing) to ensure it meets technical specifications and functions correctly with the existing MRI system. Such technical data is not detailed in this 510(k) summary, which is a high-level overview. There is no mention of country of origin or retrospective/prospective data.

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

Not applicable. As no clinical "test set" and corresponding ground truth determination are described, there is no mention of experts for this purpose.

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

Not applicable. No clinical test set or adjudication method 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 submission is for an MRI coil, not an AI-powered diagnostic tool, and no MRMC study or AI component is mentioned.

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

Not applicable. This is for an MRI coil, not a standalone algorithm.

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

Not applicable, as no clinical ground truth determination is described in this summary. The "ground truth" for an MRI coil would be its ability to accurately reflect the NMR properties of the tissue it images, which is assessed through technical performance and image quality.

8. The sample size for the training set

Not applicable. No training set is mentioned as this device is not an AI/machine learning model.

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

Not applicable. No training set or ground truth establishment for a training set is mentioned.

Summary

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992650

OCT 8 1999

Attachment 1

510(k) Summary of Safety and Effectiveness

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SUBMITTER INFORMATION: 1.0

1.1	Submitter:	Hitachi Medical Systems America1959 Summit Commerce ParkTwinsburg, OH 44087PH: 330 425-1313FX: 330 425-1410
1.2	Contact:	James Jochen Rogers
1.3	Date:	August 5, 1999
2.0	DEVICE NAME:
2.1	Classification Panel:	Radiology
2.2	Classification Number:	892.1000 Magnetic Resonance Diagnostic Device
2.3	Product Nomenclature:	System, Nuclear Magnetic Resonance Imaging
2.4	Product Code(s):	90LNH90MOS (Magnetic Resonance Specialty Coil)
2.5	Trade/Proprietary Name:	AIRIS, AIRIS II
2.6	PREDICATE DEVICE(s):	Hitachi AIRIS, AIRIS II

DEVICE DESCRIPTION: 3.0

FUNCTION 3.1
Identical to the AIRIS 510(k) K980691. Identical to the AIRIS II 510(k) K984278.

The AIRISand AIRIS II MRI Magnetic Resonance Diagnostic Devices are being enhanced by one additional RF Coil (PA/QD Shoulder Coil) to increase the clinical utility of the AIRIS and AIRIS II in the stationary configuration. The Shoulder Coil can operate either in the quadrature mode or in the phased array mode with the AIRIS II, and in the quadrature mode only with the AIRIS. The coil is available in Large and Standard sizes for both MRI systems, to accommodate a wide variety of physical patient sizes, and to achieve maximal coil filling factors. Part numbering is as follows:

MRI System	Imaging Mode	Coil Size	Part Number
AIRIS II	Phased Array	Standard	MR-PSC-51
	Phased Array	Large	MR-PSC-52
	Quadrature	Standard	MR-QSC-51
	Quadrature	Large	MR-QSC-52
AIRIS	Quadrature	Standard	MR-QSC-51
	Quadrature	Large	MR-QSC-51

AIRIS and AIRIS II software did not need to be revised in order to support full functionality of this PA/QD Shoulder Coil.

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SCIENTIFIC CONCEPTS 3.2

Magnetic Resonance (MR) is based on the fact that certain atomic nuclei have electromagnetic properties which cause them to act as small spinning bar magnets. The most ubiquitous of these nuclei is hydrogen, which makes it the primary nucleus used in current imaging experiments in magnetic resonance. When placed in a magnetic field, there is a slight net orientation or alignment of these atomic nuclei with the magnetic field. The introduction of a short burst of radiofrequency (RF) excitation of wavelength specific to the magnetic field strength and to the atomic nuclei under consideration can cause a reorientation of the proton's magnetization vector. When the RF excitation is removed, the proton relaxes and returns to its original orientation. The rate of relaxation is exponential, and varies with the character of the proton and its adjacent molecular environment. This reorientation process is characterized by two exponential relaxation times called T1 and T2 which can be measured.

These relaxation events are accompanied by an RF emission or echo which can be measured and used to develop a representation of these emissions on a three dimensional matrix. Spatial localization is encoded into the echo by varying the RF excitation and by appropriately applying magnetic field gradients in x, y, and z directions, and changing the direction and strength of these gradients. Images depicting the spatial distribution of NMR characteristics of the nuclei under consideration can be constructed by using image processing techniques similar to those used in CT.

For magnetic fields up to 1.5T. the RF frequencies commonly used range up to 65MHz. The RF fields have pulse powers from several watts to greater than 10 kilowatts, and repeat at rates from once every few seconds to greater than fifty per second. The timevarying magnetic gradient fields have a typical duration of sub-millisecond to several milliseconds.

3.3 PHYSICAL AND PERFORMANCE CHARACTERISTICS

MR is currently of great interest because it is capable of producing high quality anatomical images without the associated risks of ionizing radiation. In addition, the biological properties that contribute to MR image contrast are different from those responsible for x-ray image contrast. In x-ray imaging, differences in x-ray attenuation, largely based on differences in electro density are responsible for the contrast observed in x-ray images. In MR imaging, differences in proton density, blood flow, and relaxation times T1 and T2 all may contribute to image contrast. In addition, by varying the duration and spacing of the RF pulses, images may be produced in which the contrast is primarily dependent on T1 relaxation, T2 relaxation, proton density, or a combination of all three.

4.0 DEVICE INTENDED USE:

The MR system is an imaging device, and is intended to provide the physician with physiological and clinical information, obtained non-invasively and without the use of ionizing radiation. The MR system produces transverse, coronal, sagittal, oblique, and curved cross-sectional images that display the internal structure of the head, body, or extremities. The images produced by the MR system reflect the spatial distribution of protons (hydrogen nuclei) exhibiting magnetic resonance. The NMR properties that determine the image appearance are proton density, spin-lattice relaxation time (T1), spin-spin relaxation time (T2), and flow. When interpreted by a trained physician, these images provide information that can be useful in diagnosis determination.

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Head, Body, Spine, Extremities Anatomical Region:
. Proton Nucleus excited:
. Diagnostic uses:
- 2D T1- / T2-weighted imaging T1, T2, proton density measurements
- MR Angiography
  - image processing
· Imaging capabilities:
2D Spin Echo (SE); also with rephase
2D Gradient Field Echo (GE); also with rephase (2D GR)
2D Steady state acquisition with rewinded GE (SARGE);
- also with RF spoiling, rephasing
2D Inversion Recovery (IR)
2D Fast Spin Echo (FSE); also with rephase
2D Fast Inversion Recovery (FIR)
2D Dual Slice acquisition (SEDS)
3D Spin Echo (SE)
3D Gradient Field Echo (GE)
3D Steady state acquisition with rewinded GE (SARGE); also with RF spoiling, rephasing
MR Angiography (2D TOF, 3D TOF, half echo, high resolution/high definition, sloped slab profile, magnetization transfer contrast)
MR Fluoroscopy
RF Coil Uniformity
Adaptive Image post-processing
ACR/NEMA/DICOM 3 compliant
Aids in the performance of minimally invasive, diagnostic, and therapeutic procedures of the head, body, and extremities which may be facilitated by real-time MR guidance. Such procedures must be performed with MRI-compatible instrumentation, as selected and evaluated by the clinical user.

DEVICE TECHNOLOGICAL CHARACTERISTICS: 5.0

Identical to the Predicate Device.

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Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

OCT 8 1999

James Jochen Rogers Manager, Regulatory Affairs Hitachi Medical Systems America, Inc. 1959 Summit Commerce Park Twinsburg, Ohio 44087

Re:

K992650 PA/QD Shoulder Coil for Airis and Airis II Dated: August 5, 1999 Received: August 6, 1999 Regulatory class: II 21 CFR 892.1000/Procode: 90 MOS

Dear Mr. Rogers:

We have reviewed your Section 510(k) notification of intent to market the device referenced above and we have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the Current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General requlation (21 CFR Part 820) and that, through periodic QS inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your device in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.

This letter will allow you to begin marketing your device as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4613. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification"(21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597, or at its internet address "http://www.fda.gov/cdrh/dsma/dsmamain.html".

Sincerely yours,

Capt. Daniel G. Schultz, M.D.

Capt. Daniel G. Schultz, M.D. Acting Director, Division of Reproductive, Abdominal, Ear, Nose and Throat, and Radiological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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K992650 510(k) Number (if known): _

Device Name: Additional RF Coil for AIRIS, AIRIS II (PA/QD Shoulder Coil)

Indications for Use:

The PA/QD Shoulder Coil provides imaging of the shoulder articular anatomy and other large joints.

Head, Body, Spine, Extremities Anatomical Region: Nucleus excited: Proton Diagnostic uses:
Diagnostic uses:

2D T1- / T2-weighted imaging T1. T2, proton density measurements MR Angiography image processing

Imaging capabilities:
2D, 3D Spin Echo (SE)
2D, 3D Fast Spin Echo (FSE)
2D Inversion Recovery (IR)
2D. 3D Fast Inversion Recovery (FIR)
2D,3D Gradient Echo (GE)
2D, 3D Steady state acquisition with rewinded GE (SARGE)
2D, 3D RF-spoiled SARGE (RSSG)
2D, 3D Time-reversed SARGE (TRSG)

MR Angiography (half echo, high resolution/high definition, sloped slab profile, magnetization transfer contrast)

2D, 3D TOF
2D, 3D TOF RSSG
ECG, Peripheral Gating
RF Coil Uniformity

Adaptive Image post-processing

ACR/NEMA/DICOM 3 compliant

Aids in the performance of minimally invasive, diagnostic, and therapeutic procedures of the head, body and extremities which may be facilitated by real-time MR guidance. Such procedures must be performed with MRI-compatible instrumentation, as selected and evaluated by the clinical user.
(PLEASE DO NOT WRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use
(Per 21 CFR 801-109

OR Over-the-Counter Use
/ Semm

(Optional Format 1-2-96)

(Division Sign-Off)
Division of Reproductive, Abdominal, ENT,
and Radiological Devices
510(k) Number K992650

(Optional Format 1-2-96)

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.