With the arrival of Richard K. Osenbach, M.D., MUSC's Department of Neurological Surgery is now offering the most up-to-date surgical therapy for the treatment of medically refractory tremor. Until now, South Carolina patients had to travel out of state to get these newer treatments.

Osenbach comes to MUSC from Walter Reed Medical Center in Washington, D.C., where he was assistant chief of neurosurgery, director of stereotactic and functional neurosurgery and co-director of the Walter Reed Multidisciplinary Pain Service. He received his medical degree from Jefferson Medical College of Thomas Jefferson University of Philadelphia, and completed a neurosurgical residency at University of Iowa Hospitals and Clinics.

Osenbach received fellowship training in pain, stereotactic and functional neurosurgery at Oregon Health Sciences University under the direction of Dr. Kim Burchiel, an international leader in the fields of movement disorder surgery and pain surgery.

Surgical options for tremor

Patients with disabling tremor that is not controlled by medicine may be candidates for surgery. Two surgical options for treating tremor are thalamotomy and chronic thalamic stimulation, Osenbach said. In thalamotomy, a small lesion is made in the area of the thalamus known as the ventral intermediate nucleus.

In thalamic estimation, a small electrode is placed in the identical area targeted for thalamotomy. By using high-frequency electrical stimulation, the tremor can be suppressed. Osenbach said that while any type of tremor can be treated using these procedures, essential tremor and tremor-dominant Parkinson's disease appear to be the two best indications for surgery. Intention tremor related to multiple sclerosis, and post-traumatic tremor can be effectively treated in selected patients.

Deep brain estimation for tremor has been under investigation in Europe since 1986. During the past several years, multicenter trials conducted in the United States have confirmed that deep brain stimulation is both safe and effective in controlling tremor. The procedure was approved for general use by the federal Food and Drug Administration in August 1997.

“Thalamic stimulation is a particularly attractive option for several reasons,” said Osenbach. “It's a nondestructive procedure, it can be tested, it's reversible, and it can be ‘fine-tuned’ to the individual patient. Also, thalamic stimulation can be performed bilaterally, whereas bilateral thalamotomy is contraindicated.”

Osenbach is excited about bringing this program to MUSC in particular and South Carolina in general. “These procedures provide a tremendous amount of satisfaction because the impact upon the patient is immediate and dramatic,” he said. “It's extremely gratifying to help people with tasks of daily living such as drinking from a cup, eating, writing—tasks that most of us take for granted.”

Osenbach is creating a movement disorders group that includes Edward Hogan, M.D., David Bachman, M.D., and David Griesemer, M.D., of the Department of Neurology. The group will work together to evaluate and screen prospective patients, determine those who are candidates for surgery, assess the effectiveness of surgery, plan follow-up care and provide feedback to referring physicians.

“We also are looking into putting together a packet of information for referring physicians who prefer to pre-screen their own patients,” Osenbach said. “We hope this will give referring physicians an opportunity to interact with us here at MUSC and be a part of decision-making for their parents.”

Long-term data sought

The success rate of deep brain stimulation for controlling tremor is around 90 percent after two to three years. Osenbach is interested in looking at success rates during a longer period and plans to setup a study to follow movement disorder surgery patients longitudinally and continuously.

In addition to treating tremor with thalamotomy or thalamic stimulation, Osenbach plans to offer pallidotomy for patients with medically refractory Parkinson's disease whose primary symptom is not tremor. Osenbach also hopes to develop a program for the surgical management of adult epilepsy in the future.

Editor's note: The article is reprinted from MDialogue newsletter, a physician liaison program publication.