New UC Davis MRI provides precision without the anxiety

Reclining chair makes scans of arms, legs more comfortable

types of MRI scanners
Types of MRI scanners

A routine medical test that is uncomfortable for many people now promises to be much easier for Sacramento-area patients, thanks to new magnetic resonance imaging (MRI) technology now operating at UC Davis Medical Center.

The hospital’s new musculoskeletal MRI unit is designed to give patients a uniquely comfortable experience during scans of the arms and legs, but without compromising the power and quality of the scan.

Instead of lying in a closed tunnel or on a platform under a large magnet, patients relax in a padded reclining chair with little of their body area covered by machinery (see photographs at right). While being scanned, patients may listen to music or read a book.

“Our patients will be very comfortable,” said Marge Gorthy, chief administrative officer for the UC Davis radiology department. “They won't have to put their whole body in a machine or worry about claustrophobia. But because it's the same strength as a typical clinical MRI, the high-resolution images produced by this magnet are better than those from other MRI scanners of the same strength.” 

Comfort during scans of arms and legs

An MRI is a noninvasive procedure that uses a powerful magnet and radio waves to produce images of bones and soft tissue inside the body, without exposure to X-rays. Physicians commonly use the technique to identify musculoskeletal injuries such as torn ligaments or slipped disks, as well as problems with the brain and spine, the cardiovascular system, the reproductive system and abdominal organs.

The new MRI unit at UC Davis is designed specifically for comfort during imaging of the extremities. Patients sit in a padded reclining chair and place the affected limb inside an adjustable, donut-shaped magnet coil that is about the diameter of an automobile tire. No other machinery covers the body during the scan. 

Strength comparable to many traditional MRIs

The new musculoskeletal MRI unit at UC Davis has the same overall magnet strength as many conventional MR scanners.

Classic "closed" MRI scanners involve a closed tube or tunnel inside a much larger magnet. Many open-configuration or “open” MRI machines require patients to lie down in an enclosed space as well, but are open on the sides to decrease the feeling of claustrophobia. However, the trade-off for this additional space is almost always a magnet of lower strength — and image quality and scan time depend on the strength of the magnet.

The new musculoskeletal MRI obtained by UC Davis has the same overall magnet strength as many conventional MR scanners — typically 1.5 Tesla (1.5 T) — while open magnets are systems of 1.0 T or less.

First on West Coast

open MRI for extremities. ©2009 UC Regents
The new musculoskeletal MRI unit at UC Davis.

Patients with bone and joint problems will find the increased comfort a plus. Some studies in conventional MR scanners, such as wrist and elbow imaging, require that patients remain in uncomfortable positions for 30-45 minutes. This is hard enough for someone with only a single joint in pain, but is even harder for patients with arthritis, back or neck pain, or other chronic disorders.

Patients with rheumatoid and other inflammatory arthritis will especially benefit because MRI may permit early diagnosis — and therefore earlier treatment — without the discomfort of a conventional scan.

Manufactured by ONI Medical Systems, the high-field musculoskeletal MRI at UC Davis Medical Center is only one of two currently in use in the United States. The other is operated by Dartmouth Medical School in New Hampshire. UC Davis radiology clinicians and researchers plan to work cooperatively with ONI to develop new applications for the unit.