World's First MRI/X-RAY Imaging Suite Located at UCSF

November 15, 2001
News Office: Kevin Boyd (415) 476-8429

The first imaging suite to combine MRI (magnetic resonance imaging) with a cath lab officially opened today at UCSF Medical Center. The XMR suite, established in partnership with Philips Medical Systems, already has improved the treatment of several patients with vascular disease.

"The most exciting aspect of this suite is that, during the same operation or procedure, we can use both X-ray angiography, which clearly shows the structure of blood vessels and allows us to navigate them, and MRI, which is ideal for displaying soft tissues and revealing the progress of a treatment," said Dr. Charles Higgins, director of the XMR Center at UCSF Medical Center, and UCSF professor and vice chair of radiology.

"The suite features a floating patient table that can slide a patient quickly and smoothly from one imaging system to the other," said Joop van Vaals, director of the interventional MR business at Philips Medical Systems. "The two components of the system are installed in adjoining bays, separated by a lead- and copper-shielded sliding door. This suite combines our world-class MR and cath-lab technology, and marks a significant milestone in improvement of stroke treatment and other interventional procedures."

Among the first patients to benefit from the new system will be stroke victims who are treated with so-called clot-busting drugs to restore blood flow in the brain. X-ray angiography is commonly used in these procedures to map the blood vessels and thread a catheter to the location of the blood clot. "The challenge," said Dr. Randall Higashida, head of neurointerventional radiology at UCSF and professor of radiology and neurological surgery, "has been to deliver enough drug to break up the clot, but not so much that it causes bleeding. With the XMR suite, doctors will use the X-ray side to bring the catheter to the stroke site, then shift the patient to the MR side during drug release to monitor the return of blood to the stroke affected brain region."

The XMR suite will improve treatment of heart disease as well as stroke. Using current technology, blocked or weak arteries are held open to maintain blood flow, by introducing a tube - called a stent - into the artery, Higashida explained. While positioning the stent under X-ray guidance is effective, doctors are increasingly concerned with the high doses of X-rays that patients are exposed to during long procedures. The new system enables stents and other devices to be placed using a combination of X-ray and MR guidance.

Because no X-rays are used in an MR scanner, the X-ray dose to the patient can be reduced dramatically. This is particularly important in treating children, who have a greater risk of radiation-induced cancer when treated using conventional methods.

The MRI capability of the suite will be used in a similar way to improve other catheter-based vascular procedures, such as balloon angioplasty for narrowed arteries, angiogenesis therapy for blocked coronary arteries, and the delivery of anti-tumor drugs.

"The suite will also be used as a research tool to study new applications for MRI in interventional procedures", said Tim Roberts, UCSF's scientific director for the new facility, and assistant professor of radiology. "In addition to using MRI to complement X-ray angiography, we will use the suite to develop hardware and software required to perform interventional procedures under MR guidance alone, without the need for X-ray imaging," he said.