Brain Surgery Techniques Improved
The UC Irvine Medical Center joins 38 medical centers worldwide, only three of which are in California, in offering more promising surgical results for patients with brain tumors, pituitary tumors and epilepsy through the use of portable intra-operative magnetic resonance imaging.
This new technology was ready for use by the end of September and now makes the UCIMC the only hospital south of Los Angeles to offer IOMR. The only other units in California reside at UCLA, Cedars-Sinai and UC San Francisco.
The IOMR allows surgeons a greater ability to thoroughly remove tumors in areas where the tumor and brain appear similar in color and texture, as well as a better ability to navigate the brain by displaying any immediate shifts that occur in it during surgery. The brain has a gelatin-like consistency and, therefore, such shifts, due to the pressure of gravity on an exposed brain or the pressure of a tumor on the brain itself, could be fatal, especially since the shifts are not reflected in the pre-surgery magnetic resonance images.
Previously, hospitals would rely on frameless stereotactic image guidance, which is a standard procedure that employs a computer to reconstruct a person’s brain based on presurgery magnetic resonance images. Stereotactic image guidance and triangulation cameras provide a three-dimensional guide for surgeons to follow during surgery, but no insight into the shifting of the brain tissue during the actual procedure. IOMR can be used to enhance frameless stereotactic image guidance, so that it is more accurate and accounts for brain shifting. The frameless stereotypic image guidance may be used in less dangerous portions of the surgery until more critical conditions arise and require the neuro-imaging capabilities of the IOMR for real-time navigation.
In contrast to previous surgical procedures which relied on pre- and post-surgery images of the brain to determine its condition, the IOMR provides detailed, three-dimensional images in real-time and eliminates the potential need for patients to return to the operating room, while also reducing risks or complications that may arise during the surgery. In turn, patients may experience a shorter recovery period and less chance of post-operative complications or therapies as well.
‘Diagnostic magnetic resonance of the brain has been used since the mid 1980s,’ said associate professor and Chairman of the Department of Neurological Surgery Dr. Mark Linskey. ‘Adapting the technology for use during brain surgery is not so much a ‘discovery’ as a powerful new adaptation or application.’
The IOMR particularly assists in epileptic cases and surgeries that involve the removal of primary, metastatic and skull-based tumors. The IOMR allows the efficient removal of primary brain tumors that look similar to surrounding brain mass so that surgeons may know where the brain tissue ends and where the tumor begins.
In addition, IOMR allows surgeons to effectively remove larger pituitary tumors through the nose using an endoscope, an instrument that allows the surgeon to view images of the body’s internal organs through small incisions. The only disadvantage of IOMR is the increase in time spent in the operating room, which can be approximately an hour to an hour and a half longer than standard procedures.
Studies indicate that IOMR increases the thoroughness of brain tumor removal, as confirmed in post-magnetic resonance imaging, and resection without increasing risks of complications.
Other studies indicate that the IOMR will detect unsuspected tumor residue while still in surgery in 38 to 40 percent of cases.
IOMR works differently than traditional diagnostic magnetic resonance scanners. IOMR scanners require the anesthetized patients to remain still, as opposed to lying down and moving through a doughnut-shaped dome, while a magnet moves to wherever it is needed during the course of the operation.
‘[IOMR is] a powerful new tool to improve the quality and safety of brain surgery,’ Linskey said. ‘In our first three patients, the outcome has been excellent. We are quite pleased with the clinical results as well as the system capabilities.’