Children's Hospital Boston, in Massachusetts, recently opened its new, state-of-the-art, intra-operative MRI/OR suite. This imaging environment -- the first of its kind in North America -- is structured around a mobile magnet that is moved to the patient, allowing the patient to remain stationary during imaging. Referred to as "the future of the neurosurgery OR," the suite allows surgeons to more effectively and efficiently treat brain tumors, brain-vessel diseases, spinal tumors, and other serious infirmities. ETS-Lindgren was instrumental in helping construct the unique setting.

Weighing in at 7.5 tons, the MRI moves along the ceiling from a dedicated bay adjacent to the operating room to a space over the patient's bed. Once in place the MRI allows surgeons to take detailed images of the affected area of the body before, during and after surgery while never moving the patient.

Building an intra-operative suite with a heavy, movable 1.5T magnet -- and shielding the room so that readings were dependable and accurate -- proved a considerable challenge and a rewarding accomplishment.


The MRI moves slowly
to the patient's bed.

The design of this $5 million suite, part of a $170 million clinical expansion project, began in the Fall of 2002 with ETS-Lindgren joining Macomber Builders, the project's contractor. Together, these companies worked through the design obstacles and special considerations that occurred in this ambitious project.

"ETS-Lindgren's technical expertise was invaluable to this project," said Jim Lyons, Project Executive for Macomber Builders. "Their participation and timely response helped us keep this long-term job moving along quite nicely."

Boston's groundbreaking MRI/OR suite measures 1,000 sq. ft. which includes a 600 sq. ft. shielded room and docking station. Because the IMRIS magnet is mounted to allow for mobility, its installation created an entirely different host of obstacles for the design, construction, and optimal performance of the MRI equipment.

"It was a very complex project for both shielding and on-site installation," said ETS-Lindgren's Mike Bresnahan. "We took the existing designs and implemented them in the field--adapting, of course, to on-site conditions. Everything turned out so well, and we're very proud to be a part of such a significant milestone for this kind of application."

For the project, ETS-Lindgren provided RF shielding for a number of the suite's features, both standard and unique. "The design work for the room was already underway when we were brought on board," said Mike Bresnahan, ETS-Lindgren Project Manager," so there were already very solid requirements that we needed to work with. Some of the existing conditions in that design and in the site itself proved very difficult to shield. With our designers and expert team on board, though, we were able to work past these challenges and create a very unique suite that meets all the hospital's specifications."

One of the challenges ETS-Lindgren discovered was the sturdy rail installation that ran the length of the room allowing the 1.5 Tesla magnet to move between the magnet docking space and the OR area. As a part of the room, these rails required shielding, and contributed to the challenges ETS-Lindgren faced in shielding the enclosure.

Another challenge was the sheer volume of wires needed to facilitate the mobile magnet's movement between positions. Any wire that passes through a pipe or RF shield must be grounded, and the sheer volume of the wires involved in this application was considerable. Since the magnet travels through the suite, the wires must be long enough to follow it--and this process leads the wires through a shielded environment. Therefore, it was necessary to shield the wires
for this process, which is much more involved than shielding those in a stationary magnet application.

The presence of an electrical room directly beneath this new construction also presented a challenge. To insulate the MRI/OR suite against the considerable vibrations and interference caused by this room, ETS-Lindgren installed large filter panels that cover the suite's walls. This effectively dampens the vibrations and interference, allowing the MRI equipment to take accurate and dependable readings every time.

To complete the shielding and make it accurate for testing, ETS-Lindgren placed a number of integral components in the intra-operative MRI/OR suite. They included acoustic elements inside the walls and doors of the room, an optimized floor, and RF windows to create a more pleasant atmosphere and further enhance the patient experience. Additionally, two Auto-Seal II doors were installed in the room, and ETS-Lindgren interfaced these doors with an existing door separating the magnet docking room and the OR suite.

Finally, ETS-Lindgren installed a copper lining surrounding the entire operating room. This inventive use of technology is a breakthrough not only for medical professionals, but for patients and their families. The intraoperative MRI/OR suite will provide numerous benefits for young patients undergoing brain, heart, and cancer treatments. In addition to the increased convenience and comfort of same-site MRI and OR capabilities, the new suite will enable safer and more accurate surgical procedures by providing real-time results and eliminating the need for future follow-up surgeries.