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CONTACT: TOM MOORE
8788 John Pappajohn Pavilion
Iowa City IA 52242
(319) 356-3945
e-mail: thomas-moore@uiowa.edu

Release: Dec. 7, 1999

UI Health Care specialists' innovative use of imaging system aids in surgery success

IOWA CITY, Iowa -- Opening day of pheasant hunting season this fall was picture perfect. Unfortunately, the day turned out to be less than perfect for Mazen A. Maktabi, M.D., associate professor in the University of Iowa department of anesthesia. He was involved in a hunting accident when a single shotgun pellet struck him just below the eyebrow.

"The wound began bleeding quite a bit, and it was mildly painful, but my vision was not affected," Maktabi said.

An emergency brain CT scan performed in a nearby hospital did not conclusively locate the pellet that struck Maktabi. In fact, the pellet entered above his eyebrow, traveled under the tissues there and lodged on top of his eye.

"Had the pellet been just one centimeter lower, Maktabi probably would have lost the vision in that eye," said Jeffrey Nerad, M.D., professor in the UI department of ophthalmology and the visual sciences, who treated Maktabi. "Fortunately, that was not the case."

Since the pellet had not affected Maktabi's vision, one treatment option involved doing nothing and allowing the pellet to remain where it was. However, Maktabi preferred to have the pellet removed.

"I wanted to get it out while I am young and healthy," Maktabi said. "Sometime in the future I may need to have a MR (magnetic resonance) examination, so undergoing surgery to remove the pellet when I was older, and perhaps in poorer health, could be more risky." Magnetic resonance imaging (MRI) technology uses powerful magnets to produce an image of the body. It cannot be used in cases where patients have metal objects in their bodies.

UI Health Care specialists developed an innovative approach to help Maktabi. They used advanced imaging technology called the Stealth Station to precisely locate the pellet and remove it safely.

"We have extensive experience in using the Stealth Station in neurosurgery cases and other surgeries of the spine, head and neck," said Timothy Ryken, M.D., assistant professor in the UI department of surgery and a staff physician at the Veterans Affairs Medical Center in Iowa City. "We have used it in more than 100 cases with excellent results."

However, the Stealth System is designed for use on parts of the body that are more rigid and can be kept still -- such as the skull, brain and spine. It is not generally used in the soft tissues.

"The Stealth System helps locate abnormalities such as tumors and then provides three-dimensional images that help us plan the surgery," said John Haller, Ph.D., an assistant research scientist in the UI department of radiology. "Using it in the orbit of the eye required us to make a few adjustments."

Working with Nerad, Haller and Ryken adapted the Stealth System to help Maktabi.

"The adaptations that Dr. Haller and Dr. Ryken made to the system were very effective," Nerad said. "By using the Stealth System we were able to pinpoint the buckshot pellet and remove it safely. Knowing precisely where the pellet was meant that we didn't have to search for it during the surgery, which made the procedure less risky than it would have been otherwise."

"This was an unusual application of the Stealth System, but our goal is to develop unique applications for image-guided procedures," Haller said. "The ultimate goal is to be less invasive than traditional surgeries."

Eventually, the Stealth Station could be used in surgeries on body structures that are not rigid and may move after an image is acquired.

"We are working to expand the current system so that multiple images can be entered and merged to maximize the amount of information that is available to the surgeon," Ryken said. "I am convinced that image guidance will continue to play an increasing role in neurological procedures and that it also has great potential to benefit other patients in a wide range of situations."

"The results for me were excellent," Maktabi said. "I could not be more happy about the outcome."

The Stealth Station also has been used to locate tumors in the brain that were not found in previous surgeries. Using this technology, specialists also have been able to place flexible rubber tubes called catheters into the ventricles of the brain when standard techniques failed.

The Stealth Station has been in operation at the UI Hospitals and Clinics since July 1998.

University of Iowa Health Care describes the partnership between the UI College of Medicine and the UI Hospitals and Clinics and the patient care, medical education and research programs and services they provide.