Skull surgery is experiencing major clinical advancements, surgeons say, as minimally invasive surgery (MIS) techniques are applied to resolving a variety of brain tumors and craniofacial disorders.
"Neurosurgery and skull-based surgery are undergoing a paradigm shift," says UCSF head and neck surgeon Ivan El-Sayed, M.D. "We are using endoscopic techniques to visualize and excise lesions that we could previously only address through large, open surgeries."
Surgery for pituitary tumors is a prime example of such advancements, UCSF surgeons say. Over decades, UCSF surgeon Charlie Wilson, M.D., DSc, firmly established the utility of accessing the pituitary from below, through the sphenoidal sinus, but the operation was still an open surgery that required the surgeon to chisel away the upper palate. Since 2000, UCSF physicians have used the same sphenoidal sinus to access the pituitary, but have found that taking endoscopic equipment in through the nostril is far less destructive and gives the surgeon a better view than a microscope.
Advantages of this minimally invasive technique include avoiding the need for a craniotomy, no scarring on the face, little cerebrospinal fluid loss, little or no brain retraction, less blood loss, and a reduction in seizures or injuries that may cause future seizures. In some cases, the view is actually better with an endoscope and may allow for more complete tumor removal.
"The operation has gotten so good now that patients lose only about three tablespoons of blood and the risk of serious complications is about 1 percent," neurosurgeon Sandeep Kunwar, M.D., says. "Patients are able to go home the next day, and other than a runny nose and a sinus headache, they feel pretty good."
El-Sayed attributes the success of minimally invasive brain surgery to new technology in endoscopic equipment and in neuroradiological imaging for preoperative planning and for guiding physicians during surgery. "Imaging these days is light-years ahead of where it was a decade ago," he says.
The skills necessary to do such surgery have been carefully acquired over years, El-Sayed says. "This is not something we just decided to do one day. This is something upon which we have gained experience in incremental steps." At first, he says, surgeries were open surgeries, while the endoscopic instruments were used to assist in visualizing tumors. Only after many such experiences did the surgeons begin to do the operation purely as a minimally invasive, endoscopic procedure.
"One of the concerns now is that, as it becomes obvious that this MIS is the way to go, physicians will start advertising that they can do it before they have sufficient training," El-Sayed says. UCSF is currently developing a skull-based surgery laboratory, part of which will be devoted to training future surgeons in the technique, he says.
During many operations, surgeons from different specialties collaborate. Neurosurgeons, head and neck surgeons, and rhinological surgeons may be involved during various parts of the operation. Some pituitary tumor operations require an otolaryngology specialist to guide the endoscope into place and a neurosurgeon to excise the tumor.
UCSF surgeons feel that MIS techniques have the potential of being applied to a wide variety of cranial problems. "We are seeing that there are a lot of open spaces in the head that can be used" to access lesions, Kunwar says.
Dr. Ivan El-Sayed can be reached at (415) 353-2757.
Dr. Sandeep Kunwar can be reached at (415) 353-7500.
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