Functional and Stereotactic Neurosurgery
Functional neurosurgery includes a range of minimally invasive and highly effective treatment options for neurological disorders in both children and adults, such as:
- Patients with complex pain disorders refractory to medications are evaluated by our multidisciplinary team of neurosurgeons, neurologists, anesthesiologists, physiatrists, and psychologists. Patients with intractable pain may be appropriate candidates for neurosurgical interventions such as microvascular decompression, radio-frequency lesions, and deep-brain or motor-cortex stimulation, or neuroablative procedures such as a thalamotomy or DREZ procedure.
- Patients with movement disorders who are not responding to medication, such as Parkinson's disease, essential tremor and dystonia, are assessed by a multidisciplinary team in order to ascertain whether they are appropriate candidates for a functional intervention.
- For adult patients who suffer from severe spasticity secondary to spinal cord injuries, progressive neurological degenerative disorders, or birth defects, a program for the surgical management of spasticity is available. A physiatrist with special expertise in spasticity is part of the team.
- Surgery is now an option for many children with debilitating spasticity or impaired movement and balance. When oral medication fails, spasticity may be reduced through the use of an implantable pump that delivers an antispasmodic medication directly to the spinal cord. In some cases, balance may be improved with a surgical technique called rhizotomy, which removes the damaged motor/reflex nerve roots located at the base of the spine.
- Movement also may be impaired by injury to the brachial plexus, a network of nerves located in the neck and shoulder. Brachial plexus injuries usually occur during birth, affecting up to 2 out of 1,000 babies. While some brachial plexus injuries may heal on their own, surgical repair may be needed to prevent permanent neurological damage.
Techniques for monitoring the brain (neurophysiologic monitoring) are used during functional procedures to locate regions of abnormal function in the brain. The surgical and medical techniques include:
- Deep brain stimulation - to treat patients with essential tremor and tremor resulting from some forms of Parkinson's disease. This therapy involves the placement of electrodes deep within the brain. The electrodes are then connected to an implantable device that can generate various amounts of electrical current to the exact areas of the brain responsible for the tremors. Using a hand-held magnet, the patient can turn on the device, which is implanted in his upper chest, and the electrical current blocks the signals in the brain that cause the tremor.
- Pallidotomy - To treat akinetic rigidity (which is often seen in patients with Parkinson's disease or who have experienced a stroke), surgeons place a lesion, a controlled destruction of the brain tissue, in the globus pallidus region of the brain.
- Thalamotomy - This procedure involves the placement of a lesion in the thalamus for relief of hypertonic tremors that affect patients with Parkinson's disease, multiple sclerosis, stroke, essential tremor or post-traumatic tremor.
- Implantable drug infusion - Implantable pumps that deliver medication directly into the spinal column are used to administer morphine for pain control or baclofen, an antispasmodic medication that replaces a chemical that normally allows muscle relaxation.
- Spinal cord stimulators - Surgeons can relieve some types of chronic pain by electrically stimulating the spinal cord through the use of an implanted pulse generator.
- Gamma knife stereotactic radiosurgery - the most advanced technology available in radiosurgery. It is a safe, non-invasive, high-precision device that treats many types of tumors and lesions, including deep-seated brain tumors and arteriovenous malformations (AVMs).
Stereotactic radiosurgery is a non-invasive procedure performed on an outpatient basis. This technology delivers radiation to a tumor, while effectively sparing the surrounding tissues and nerves. Radiosurgery is not surgery in the conventional sense, as no opening is made in the skull. Radiosurgery describes the use of intense radiation delivered to a tumor. It may be used instead of, or in addition to, conventional surgery. In certain cases, it may offer similar benefit and lower risk or discomfort than conventional surgery. Patients can avoid both hospitalization and anesthesia.
Stereotactic radiosurgery is performed using highly advanced computers to locate and create a three-dimensional image of a tumor. Stereotaxy adds depth to imaging, where conventional x-rays can only measure height and width. This enhances the neurosurgeon's ability to precisely map the location of the tumor and find the best and safest pathway to removing it. Stereotactic techniques may be used to prepare for a surgery, during biopsy or tumor removal, while implanting radiation pellets, or to provide a navigation system during surgery. These techniques are especially useful in locating and radiating tumors deep within the brain, such as brain stem and thalamic tumors.
Stereotactic radiosurgery has been used for more than 30 years for the non-invasive treatment of benign and malignant tumors, vascular malformations, and other disorders of the brain. To date, more than 100,000 patients have been treated worldwide. Although developed originally for use in the brain or other intracranial targets, stereotactic radiosurgery is rapidly becoming recognized as a useful treatment technique for tumors and vascular malformations of the spine and spinal cord as well.
- Radiosurgery is a term describing precise localization and delivery of radiation to an intracranial target. Originally, it was used by neurosurgeons to produce tiny, circumscribed, non-invasive lesions in the brain for movement disorders and pain.
- Stereotaxis refers to the precise localization of an anatomic target in 3-dimensional space, and radiosurgery is a term that now describes any precise, tightly circumscribed delivery of radiation, usually as a high dose in a single fraction, to a defined anatomic target. Multiple fractions may be used, a procedure termed stereotactic radiotherapy.
- Together, they are an important means of treating both benign and malignant tumors as well as vascular malformations located near critical radiosensitive structures, such as optic nerve or spinal cord. Utilization of this treatment technique outside the head has been quite limited so far, but many of the technological hurdles are being overcome, and the future of stereotactic spinal radiosurgery is rapidly approaching.