Attachment_Number_Five_-_NMRF-7T-StatementOf_work_06292016_REV.docx

STATEMENT OF WORK

Project Title: Acquisition of a 7 T Human MRI Scanner for NIH MRI Research Facility (NMRF), National Institute of Neurological Disorders and Stroke (NINDS) Project Background

This project originates from the NIH MRI Research Facility (NMRF) in the intramural program of the National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH) in Bethesda, MD.

NMRF is trans-NIH resource for high-field human magnetic resonance imaging (MRI) and spectroscopy studies. Its function is to serve as a resource by which all NIH institutes can perform MRI studies that further the understanding of healthy and diseased brain anatomy, function and physiology. The NMRF currently operates a 3T human MRI system.

Over the last few years, MRI at 7 T has advanced significantly. To continue to support cutting- edge research performed by NIH researchers, it is necessary that the NMRF have the most modern equipment available to provide researchers with access to the latest equipment, tools, and techniques for their experiments.

Project Objective

Acquisition of a 7 T MRI system to replace the current 3 T MRI system. This system will be used for clinical and preclinical research.

Project Requirements

The NMRF/NINDS requires a 7 T MRI and spectroscopy system suitable for human studies that will consist of a 7 T superconducting magnet, active shim and gradient systems, radio frequency electronics and an operator console. The 0.5 mT contour of the magnet fringe field shall be contained within a 6.0 m x 9.7 m size room. The magnet shall be delivered to the site through a roof hatch of size 2.7 m x 3.3 m.

The requirements for each component are given below. However, the vendor is encouraged to offer a system with best possible specifications, and the proposed enhancements will be considered and evaluated during the technical review of the quotations.

1) Magnet

a) Superconducting and actively shielded magnet shall provide a field strength of 7.0 T (Tesla) in the horizontal direction.

b) The inner diameter of the room temperature bore of the magnet shall be at least 82 cm.

Attachment Number Five

c) Field homogeneity (fully shimmed with superconducting and/or passive shims) shall be less than 5 ppm peak-to-peak over a 45 cm diameter spherical volume (DSV) and the water spectral line-width shall be less than 0.1 ppm full width half height (FWHH) over a 25 cm DSV.

d) Drift of the main field shall be less than 0.05 ppm/hour and 0.005 ppm/hour without and with field drift compensation, respectively.

e) The magnet shall not consume liquid helium (zero boil-off) when the MRI system is not in use.

f) The vendor shall provide a switch to shut-off the main field quickly and safely in case of an emergency. The location of the switch is to be determined during system installation.

2) Room temperature shim and gradient coils

a) The room temperature active shim coil set shall consist of at least 11 channels (x, y, z, 5 second order, and 4 third order terms) and a power supply. The second order channels (z2, xz, yz, x2-y2 and xy), at full duty cycle, shall be able to generate field of at least 20 Hz/cm2 at the isocenter of the magnet. The third order shim set shall consist of z3, z2x, z2y and z(x2- y2) channels.

b) All room temperature active shims shall be under computer control within the software environment used to run the rest of the console.

c) The inner diameter of the gradient (along x, y, z axes) coil set shall be at least 60 cm.

d) The gradient amplifiers shall be capable of generating at least 45 mT/m magnetic field gradient along each axis with a slew rate of at least 200 T/m/s.

e) Field deviation due to gradient non-linearity shall be less than 8% at any location over a 300 mm diameter sphere.

f) Duty cycle at 100% power (all axes enabled) shall be at least 30%.

g) An eddy current compensation unit under computer control with at least B0, x, y, z shall be supplied. After eddy current calibration by the manufacturer, the residual amplitude of eddy currents terms at 1 ms after the gradients are switched-off shall be within 0.1%.

h) The gradient waveform control unit shall operate with at least 10 sec time resolution, 16 bit amplitude resolution and 128k word memory.

i) The gradient field stability will be better than 0.5% at maximum gradient strength on each axis.

j) The equivalent A-weighted sound level (LAeq) within the empty bore (at iso-center) of the 7T magnet and at bore entry shall be less than 110 dBA when using a 3 mm resolution (isotropic), minimum echo-spacing, single-shot EPI pulse sequence without acceleration with read gradient applied in any principal direction.

k) There shall be a hardware/software mechanism to protect the gradients and gradient amplifiers from overheating.

3) RF Electronics

a) Transmitter system

i) RF transmitter shall operate either as a single channel or a parallel transmit array of eight (8) independent channels at the 1H frequency at 7 T (~298 MHz).

ii) RF transmit amplifiers should supply at least 8 kW pulsed, linear, power at 298 MHz when operated in the single channel mode. In the parallel transmit mode, each transmit channel amplifier shall be capable of delivering at least 1 kW.

iii) RF transmitter shall contain at least one broadband channel covering the frequency range of 10-298 MHz for non-proton imaging and spectroscopy studies.

iv) The broadband power amplifier shall be capable of delivering at least 8 kW.

v) The 1H transmit system shall be configured to allow 1H decoupling during 31P and 13C spectroscopy studies.

vi) All RF channels shall be driven by independent waveform generators with at least 256 k waveform memory and capable of amplitude and phase modulation. Frequency and phase control shall be within 0.1 Hz and 0.05 degrees, respectively. A minimum of eight separate pulse shapes shall be able to be used within one pulse sequence. There shall be at least 40 dB amplitude gain and RF pulse timing resolution shall be at least 2 microseconds.

vii) RF transmit power monitoring shall be provided on all individual channels with an automatic mechanism to shutdown all amplifiers to ensure that the estimated local and average SAR remains below the FDA/IEC guidelines. In addition, a software mechanism shall be provided to limit the RF power to individual transmit elements.

b) Receiver system

i) The RF receiver shall contain at least 64 digital receivers capable of receiving MRI signal at 298 MHz in parallel.

ii) At least eight (8) of the receiver channels shall be broadband (10-298 MHz) capable of receiving MRI signals of nuclei such as 1H, 19F, 31P, 13C, and 23Na.

iii) Receivers shall have at least 500 kHz bandwidth with 16 bit dynamic range.

iv) The noise figure of the receiver preamplifiers shall be less than 0.5 dB. The total system noise figure shall be less than 1.5 dB for each receiver channel.

v) Selection of which receiver channel is used shall be under computer control. Software that enables all receivers to be used within the full range of imaging sequences shall be available.

c) RF coils and T/R switches

i) The vendor shall provide the following integrated RF coils suitable for 1H MRI of the human head:

· Single channel volume transmit and 32 channel receive array (1Tx/32Rx)

· Eight channel transmit array and 32 channel receive array (8Tx/32Rx)

· Single channel surface, receiver coil (5 cm diameter)

ii) Transmit-receive switches that will operate at 31P, 13C, and 23Na frequencies shall be provided.

iii) The vendor shall provide a mechanism to allow the use of customer developed RF coils.

d) External gating and Monitoring

i) There shall be the capability of gated acquisition of data with a minimum of two (2) independent external signals

ii) There shall be a minimum of 4 BNC TTL output lines.

iii) The system shall provide respiratory and cardiac monitoring with a real time output and internal recording (saved file on disk) for both signals.

4) Console

a) The vendor shall supply a state-of-the-art host computer with current scanner operation and image viewing software. The system shall come equipped with software for acquisition and processing of advanced neuro-MRI and spectroscopy (1H and other nuclei) applications. The system also shall come equipped with automatic shimming software to optimize all active shims for each subject.

b) The system shall be capable of acquiring and real time reconstruction of 32 channel data with accelerated (R4) gradient-echo echo planar imaging (GE-EPI) for 30 min at 128x96 resolution and maximum slices per TR.

c) At least 250 GB disk storage for reconstructed images and at least 250 GB for raw data storage shall be provided.

d) 1 Gb or 10 Gb ethernet for general network communications with external computers.

e) The vendor shall supply the source code of purchased pulse sequences and off-line software tools to enable customer research and development of pulse sequences and image reconstruction techniques.

5) Scanner table

a) A scanner table shall be provided for positioning of subjects at the isocenter of the magnet.

b) The table must be compatible with supplied gradients and designed to minimize vibrations.

c) There must be a mechanism to landmark and ensure accurate positioning of the subject in the isocenter of the magnet. Subject positioning controls shall be located on the magnet cover near magnet bore entrance.

d) The scanner table shall be able to operate at low and high speed modes. The low speed mode shall be suitable for human studies.

6) Warranties

The vendor shall,

a) Provide warranty for all parts and labor to repair any defects or failure in supplied items for one year from the date of Government acceptance of the system.

b) Guarantee to upgrade at no additional cost any components that become outdated due to advances in design made by the vendor for within the one-year warranty period.

c) Supply any software upgrades free of charge within the one-year warranty period.

7) Delivery and Installation

The vendor shall deliver and install the complete system on-site (including all connections to quench ducts, vacuum pumps, cryogens for magnet ramp up etc.) and ensure that the initial performance of all equipment satisfies the required specifications within 18-24 months following contract award.

8) Acceptance conditions

The vendor shall,

a) Demonstrate minimum specifications given for each item above including magnetic field drift and homogeneity, gradient performance, multiple receiver acquisition, image reconstruction, RF coils, RF power delivery and monitoring are met or exceeded in accordance with their proposal(s).

b) Demonstrate that the final field homogeneity using the superconducting/passive and active shims meets the following specifications when using a spherical oil phantom:

· Less than 25 Hz FWHH, < 75 Hz at 10% height, and < 250 Hz at 1% height over a 35 cm DSV.

· Less than 10 Hz FWHH, < 30 Hz at 10% height, <100 Hz at 1% height over a 25 cm DSV.

· Less than 2 Hz FWHH, < 6 Hz at 10% height, < 20 Hz at 1% height over a 3 cm DSV.

c) Demonstrate the ability, using a graphical user interface, to prescribe the geometry and location of targeted area of interest, the imaging experiments listed below in principal and oblique scan planes with minimal field of view allowed by the maximum gradient strength and receiver bandwidth. In all cases, the ghosting artifacts shall be less than 1% of average image intensity. There shall be no evidence of RF noise in the images.

· Multiple-slice, multiple-echo image sets of up to at least 1024 x 1024. Capability for T1 weighting with inversion recovery. Capability of fat suppression.

· Multiple slice gradient echo images of at least 1024 x 1024 with a TE of 2 ms and a TR of 5 ms.

· Demonstrate the ability to perform sequences such as magnetization prepared rapid acquisition gradient-echo, fluid attenuated inversion recovery, fast spin-echo and MR angiography.

· Gradient-echo (GE) and spin-echo (SE) echo-planar imaging (EPI). The pixel-wise temporal standard deviation (tSD) of the image signal (GE-EPI, 32 channel coil, 2.5 mm isotropic resolution, TR 2 s, minimum-full TE, unaccelerated, 150 volumes, oil phantom) without detrending shall be less than 3 times the tSD of a noise region without signal. The tSD of the mean signal within an ROI (400 pixels, at the center of the slice at iso-center) shall be less than 0.3% of the mean signal. The amplitude of the EPI image ghosts shall be less than 3% of the mean signal intensity.

· Demonstrate acquisition and real time reconstruction of 32 channel data with accelerated (R4) gradient-echo echo planar imaging (GE-EPI) for 30 min at 128x96 resolution and maximum slices per TR.

· Demonstrate acquisition and reconstruction of multi-band (simultaneous multi-slice) EPI using a 32-channel receiver array.

· Demonstrate diffusion-weighted MRI with SE-EPI on an oil phantom with following parameters: 2 mm isotropic resolution, 80 slices, b-value =3000 s/mm2, greater than 60 diffusion directions, TE= 100 ms (full k-space), TR=11 s, and in-plane acceleration factor =2. The amplitude of the EPI image ghosts shall be less than 3% of the mean signal intensity without diffusion weighting.

· Demonstrate chemical shift imaging with 1H and 31P on concentrated test phantoms.

· Demonstrate the ability to perform with a graphical user interface the localized spectroscopy experiments (e.g. STEAM and PRESS) with 1H and 31P. Suppression of signals outside the selected voxel shall be greater than 95%.

9) Add-options

These add-options should be priced as separate line items in your proposal and be added after the sub-total in order to reflect an actual pricing structure.

a) The vendor shall provide an option to extend the warranty from one to three years for the magnet and the cryo-refrigeration system.

b) The NMRF/NINDS currently owns a 3T MRI system (Siemens Skyra, 70 cm bore magnet, 45 mT/m amplitude and 200 T/m/sec slew rate gradients, dockable table, 32 and 20-channel head arrays, 32-channel spine array and multinuclear capability) which will be replaced by the 7T system requested in this solicitation. Vendor shall provide a price for this existing 3T system if it is traded-in as a part of this contract.

c) The vendor shall provide additional price for a turn-key installation of the system which includes all site preparation and modification as well as work required to meet NIH design requirements and review. Inspection and architectural drawings of the site can be made available to assist in preparation of the quotation.