February 12, 2003

By Christine Martin

Important developments in neurosurgery offer expanded options for functional assessment and surgical management of many chronic neurological disorders and other diseases of the brain. Jeffrey Elias, M.D., newly recruited assistant professor of neurosurgery, explains how cutting-edge functional and stereotactic procedures now used at the University of Virginia Health System can dramatically improve quality of life for people with such debilitating conditions as Parkinson’s disease, epilepsy and chronic pain.

"Stereotactic procedures involve three-dimensional localization of specific areas of the brain," explains Elias. Although stereotaxis is not new, advances in imaging using high-resolution magnetic resonance imaging (MRI) or computer tomography (CT) scan and computer-assisted navigation now enable surgeons to approach discreet surgical targets deep within the brain with great accuracy. "Imaging is so good that now we can predict where specific functional regions of the brain, such as speech, motor, sensory and memory, are located," notes Elias.

Because functional areas are not anatomically well-defined within a localized region, surgeons also rely on intraoperative methods to verify the function of nuclei (masses of nerve cells) and thereby pinpoint the optimal site for surgical intervention.

Microelectrode recording, a highly precise intraoperative technique used in only a handful of medical centers on the East Coast, including U.Va., involves guiding a delicate electrode into the desired target through a small hole drilled into the cranium and recording the activity of individual neurons within a nucleus. "Because a nucleus of nerve cells gives off a characteristic discharge pattern, we are able to differentiate nuclei from the recordings," Elias explains.

The technique is an important stage in several sophisticated neurosurgical procedures offered at U.Va., including deep brain stimulation, which is used to treat movement disorders such as Parkinson’s disease and essential tremor, epilepsy, chronic pain and some psychiatric illnesses such as obsessive compulsive disorder. "Many of our patients are not able to perform the most basic of activities of daily living, such as walking, feeding oneself, dressing, bathing and writing, without deep brain stimulation or other surgical interventions," says Elias.

Neurosurgeon Jeff Elias, M.D., uses the Medtronic electrical brain stimulation system, which fits inside a briefcase, to adjust devices that were implanted in patient Carlton Rowland, who has Parkinson's disease. As soon as the initial stimulator adjustments were complete, Rowland's ability to walk improved notably. Physicians can adjust levels and parameters of stimulation using a computer on the surface of the skin, and patients also have the ability to activate the stimulator usinga handheld controller whenever therapy is needed for functioning.

Elias likens the deep brain stimulator to a cardiac pacemaker: "The stimulator is implanted into the brain and connected via an insulated wire to a generator, which is implanted under the clavicle. Microelectrode recording facilitates the accurate placement of the device. Using mild electrical pulses, the stimulator alters the function in one of the deep nuclei of the brain in a more favorable manner without destroying the brain’s circuitry."

Unlike alternative therapies, deep brain stimulation is reversible and adjustable. "For now, physicians can only make adjustments to the therapy. But soon, patients will be able to tailor their own therapy, which is important as each patient is the expert on his/her own disease," says Elias.

Elias also performs "awake surgeries" to assist with functional assessment of the eloquent regions of the brain. "There’s been a recent resurgence in awake surgery due to improved anesthetic techniques and becausea advances in stereotaxis allow surgeons to map out and operate in regions of the brain once thought to be too risky because of their involvement with motor, sensory and speech functions," explains Elias.

The process involves stimulating the cortex to observe and monitor the patient’s response. "The patient can tell us, for example, if he or she feels a contraction or tingling in the hand," describes Elias, who recently used the procedure to plan the removal of a brain tumor without causing injury to surrounding structures.

Elias also specializes in surgical treatment of incapacitating chronic pain using neuromodulation, implanted therapies that use electrical stimulation to the spinal cord or medication pumped into the spinal fluid to alter the nervous system in a way that interferes with pain signals. "Historically, ablative techniques, such as cutting a nerve or the spinal cord or creating a lesion in the brain, have been used to relieve pain. But you cannot always predict the results of ablative techniques, which are permanent and sometime lead to more painful conditions than experienced before surgery," says Elias. "Neuromodulation is a much safer and more effective alternative, which is completely reversible and adjustable."

People who may be helped by functional therapies are evaluated at U.Va. using a multidisciplinary approach, which includes neurologists, neurosurgeons, pain specialists and neuropsychologists. "A lot of people wait to pursue neurosurgery until after they’ve exhausted all other medical and pharmacological options. But we advise looking into surgical options earlier because they offer people such great benefits without the risk and side effects of medications," which, notes Elias, usually are reduced substantially following surgery.

Elias believes that, over time, increased physician and patient awareness will cause these types of therapies to become mainstream treatment options. "What is so exciting to me about functional neurosurgery is that the potential applications are unlimited," says Elias, who intends to develop a research and training center in stereotactic and functional neurosurgery at U.Va.

He adds: "Even though most of the neurological conditions we deal with are not yet curable, the fact that we can substantially reduce the severity of the disease for the patient and thereby improve functioning and quality of life makes surgical management very worthwhile."

For more information:

Jeffrey Elias, M.D.
Department of Neurosurgery
(434) 924-8277
E-mail: ble4x@virginia.edu