# Tabletop liquid-helium-free, persistent-mode 1.5-T/70-mm osteoporosis MRI magnet

> **NIH NIH R01** · MASSACHUSETTS INSTITUTE OF TECHNOLOGY · 2020 · $638,882

## Abstract

Less than half of at-risk Americans are screened for osteoporosis, a potentially debilitating age-
associated disease in which metabolically-driven bone loss leads to fragile bones and increased
risk of fracture. By imaging the trabecular network microarchitecture at high spatial resolution,
and measuring the bone mineral and bone matrix content, (full 3D bone density, degree of
mineralization, cortical thickness, histomorphometry statistics) MRI potentially can characterize
bone to a far more complete degree than DXA, quantitative computed tomography (QCT), or
even peripheral microcomputed tomography, with complete avoidance of exposure to ionizing
radiation. MRI of course is generally a very expensive technology requiring extensive hospital
real estate, infrastructure and support facilities. However, a novel superconducting magnet
technology based on the high-temperature superconductor (HTS) magnesium diboride, MgB2,
and solid nitrogen (SN2), promises a new generation of inexpensive MRI magnets which
completely dispense with the use of liquid helium coolant that has recently undergone a series
of supply and cost crises, threatening MRI scanners worldwide. In this project we develop a
tabletop MgB2 MRI magnet prototype as a demonstration of this new magnet technology. The
magnet, to be integrated into a phalangeal MRI scanner prototype, will be readily sited
anywhere, and which could be used for universal screening for metabolic bone disease.
 The specific aims of this project are: 1) completion of a tabletop, persistent-mode, liquid-
helium-free, cryocooled superconducting (MgB2) 1.5-T/70-mm bore MRI magnet prototype for
phalangeal scanning for osteoporosis research; 2) demonstration, by Dr. Jerome Ackerman
(Co-I) of the Martinos Center, MGH, of the potentially huge benefits of MgB2/SN2 technology for
MR magnets in the context of a very compact affordable scanner—he will measure 3D bone
mineral and matrix density and trabecular microstructure of the 5th distal phalanx of the
left hand by solid-state MRI. The innovative magnet design concepts include the first-ever
persistent-mode operation in high-temperature superconducting magnet and inclusion of solid
nitrogen (SN2) in the cold chamber. These features result in: 1) a field strength and temporal
stability respectively at least ~3 times greater and far better than that of a tabletop permanent
magnet, because while this magnet operates in persistent-mode, permanent magnets are highly
temperature sensitive; 2) persistent-mode magnet operation, nominally at 14 K, for a period of
~10 hours with the cryocooler off, provides a vibration-free environment for osteoporosis MRI
measurement; and 3) the whole unit is compact enough to be placed on a table.

## Key facts

- **NIH application ID:** 9878846
- **Project number:** 5R01EB022062-04
- **Recipient organization:** MASSACHUSETTS INSTITUTE OF TECHNOLOGY
- **Principal Investigator:** Yukikazu Iwasa
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $638,882
- **Award type:** 5
- **Project period:** 2017-04-01 → 2023-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9878846

## Citation

> US National Institutes of Health, RePORTER application 9878846, Tabletop liquid-helium-free, persistent-mode 1.5-T/70-mm osteoporosis MRI magnet (5R01EB022062-04). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/9878846. Licensed CC0.

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