At Penn Medicine’s Brain Tumor Center, the spectrum of surgical options for tumors near the eloquent regions of the brain includes awake craniotomy, which employs intraoperative functional MR imaging and brain mapping to delineate the relationship between infiltrative glial tumors and the speech and motor pathways of the brain. Performed while the patient is semi-conscious and responsive, awake craniotomy permits neurosurgeons to maximize tumor resection, preserve functional tissue within the motor and speech cortex, and reduce or avoid neurological deficit. Moreover, in low-grade glioma, extent of resection is an independent predictor of survival.
During awake craniotomy surgery, the patient is sedated while electrical stimuli are induced on the brain surface by the operating neurosurgeon. The patient is then wakened and his or her conscious reaction to this stimulation is used to tailor a motor and/or speech map of the brain. This map permits surgeons to maximize tumor removal while preserving functional tissue during surgery with minimal neurological risk to the patient.
The benefits of collaboration are especially evident during awake craniotomy surgery, which requires the seamless coordination of surgeon and anesthesiologist to achieve a high level of interaction between surgeon and patient and the balance of states of waking and sedation. In addition to neurosurgeons, the team includes a neuroradiologist, who provides functional MRI scans during the procedure, neurologists/neurophysiologists to assess functional speech and brain electrical recordings, and nurse practitioners and trained operating room nurses, who facilitate the use of surgical technologies required in these brain tumor cases.
Case Study
After experiencing several seizures, Mr. S, a 61-year-old male, underwent resection of an oligodendroglial brain tumor of the left temporal lobe in 2002, followed by standard radiation therapy. Following his surgery, he was highly functional with only rare seizures and returned to work as a practicing nurse anesthetist. In July 2017, however, he noted an increase in his seizure frequency and underwent a repeat MRI that showed increased infiltrative left temporal tumor with close proximity to the language cortex.
Mr. S then underwent a functional MRI that allowed mapping of his speech center in a non-invasive manner. This MRI scan was performed at the same time as an image-guided MRI, allowing for precise intraoperative localization of the tumor with an accuracy of less than 1mm. The cumulative data indicated that Mr. S would be ideal for awake surgery with intraoperative speech mapping, and after counseling, he agreed to this approach.
In the operating room, direct cortical stimulation was performed by the surgical team and the data were analyzed by anesthesiologists and neurophysiologists. The surgical team was able to maximize tumor resection while at the same time minimizing manipulation of critical language cortex. Post-operatively, Mr. S was without a speech deficit and the post-resection MRI scan indicated a near complete tumor removal in a highly infiltrative recurrent oligodendroglial brain tumor. The resected tumor tissue was then subjected to cytogenetic and molecular analysis to allow for a more rational treatment selection.
Access
Penn Neuroscience Center
Perelman Center for Advanced Medicine
South Pavilion, 2nd Floor
3400 Civic Center Boulevard
Philadelphia, PA 19104
Penn Neurosurgery
Pennsylvania Hospital
Washington Square West Building
235 South 8th Street
Philadelphia, PA 19106
Penn Medicine University City
8th Floor
3737 Market Street
Philadelphia, PA 19104