Minimally Invasive Brain Surgery Has Multiple Benefits, Study Finds
Published May 2010
A minimally invasive endoscopic procedure holds promise for safely removing large brain tumors from an area at the bottom of the skull, near the sinus cavities, clinical researchers at the Brain Tumor Center at the UC Neuroscience Institute (UCNI) at University Hospital have found.
The findings, published in the April 2010 issue of Journal of Neurosurgery, have important implications for patients with large pituitary tumors (macroadenomas).
"This is the first time that a quantitative advantage has been shown for the use of endoscopy in cranial surgery,” says Philip Theodosopoulos, MD, principal investigator of the study, director of skull base surgery at UC and a neurosurgeon with the Mayfield Clinic.
"This signals the dawn of a new era in minimally invasive cranial surgery. We have moved from the realm of assessing whether it is feasible to studying its clinical effectiveness. In this way, it is slowly starting to change from a novelty to standard treatment, setting the bar for the quality of surgical outcomes higher than ever before.”
Although tumors of the pituitary gland are benign, pituitary macroadenomas can wreak havoc, causing acromegaly (an overproduction of growth hormone), Cushing disease (an overproduction of the hormone cortisol) and hyperthyroidism, as well as visual problems, headaches and dizziness.
When removing pituitary macroadenomas (tumors that are larger than 10 millimeters), surgeons have employed three distinct routes to the tumor:
• Through the skull in a procedure called a craniotomy.
• Through an incision under the upper lip and then through the septum, which must be split apart.
• Through the nostrils—a trans-nasal approach—without an incision.
The endoscopic transsphenoidal approach, Theodosopoulos says, follows natural anatomical corridors and causes less disruption of nasal tissues.
This approach, as the new study reveals, also holds benefits related to complete tumor removal, which is important for the patient's quality of life.
Removing an entire pituitary macroadenoma can be difficult because the tumor’s growth pattern can cause it to extend through the sinus corridor, which is out of the surgeon’s view.
Surgeons can ensure that the entire tumor has been removed by using a technology known as intraoperative MRI, or ioMRI.
The surgery-prolonging technology enables surgeons to take MRI scans while the patient is still under anesthesia and on the operating table.
An endoscopic approach, by contrast, allows the surgeon to check for remaining tumor with "intrasellar endoscopy.”
Using a tiny, sophisticated camera on an angled endoscope, the surgeon can peer around bends and into crevasses to identify any remaining tumor.
"The endoscopic approach holds the potential for less invasive treatment for all patients and more complete tumor resections for individuals treated in hospitals without access to intraoperative MRI,” Theodosopoulos says.
The study showed that maximum tumor removal can be successfully achieved with endoscopy and without intraoperative MRI, Theodosopoulos says.
He adds, however, that the findings could be strengthened by a larger study.
To read more about this study go to healthnews.uc.edu and search keywords, "brain surgery.”