Summer 2012

Diagnosis and Treatment of Peripheral Nerve Disorders

"Interdisciplinary care combined with good clinical judgment is the best option for treating the entire spectrum of peripheral nerve disorders," says UCSF neurosurgeon Michel Kliot, M.D., of the UCSF Center for Management and Surgery of Peripheral Nerve Disorders.

Dr. Michel Kliot

Dr. Michel Kliot

Combining interdisciplinary clinical expertise with leading-edge equipment provides more-precise diagnoses and timelier, more effective treatment for common and uncommon entrapment syndromes, traumatic nerve injuries, peripheral nerve tumors and neurofibromatosis.

Comprehensive Diagnoses

Given the complexity of peripheral nerve disorders, Kliot says it's important to begin with a neurological workup that involves at least four components: self-reported symptoms, clinical findings, electrodiagnostic studies and imaging.

Like a table, Kliot says, a diagnosis is most stable when supported by three or four of the above "legs." Sometimes a fifth diagnostic leg adds stability, such as when Botox injected into relevant muscles helps clinicians diagnose thoracic outlet syndrome of the upper extremity or pyriformis syndrome of the lower extremity.

Advanced imaging modalities and experience reading the images can add to the certainty and specificity of the diagnosis. The UCSF neuroradiology group has pioneered technologies like high-resolution MRI and ultrasound for nerves. New MRI protocols allow the clinical team to see nerve fascicles and their relationship to pathology, thus providing a preoperative road map that helps surgeons avoid damaging nerve fibers. Certain pulse sequences can help distinguish malignant from benign tumors.

"And a more specific diagnosis leads to a more appropriate treatment plan," says Kliot. "For example, for neurofibromatosis, many tumors can be watched with serial clinical exams and imaging studies. It comes down to fully informed clinical judgment. The decision to not operate is just as important as the decision to operate."

Experienced Surgical Teams

When tumors need to be removed, Kliot says his team's experience improves patient safety.

MRI image

An MRI of a median nerve sheath
tumor in the upper arm, using
standard pulse sequences.

"During surgery, we can quickly determine if a tumor is cooperative and will shell out easily, leaving minimal or no deficits — or if it is stickier to adjacent functioning nerve fibers and requires a less aggressive resection to preserve function," he says. "That makes a difference in the life of a patient.

"We have a great team of intraoperative electrophysiologists who help us avoid damage to functioning nerves during surgery."

MRI image

An MRI using diffusion showing
green nerve fibers encircling
the tumor.

When tumors are malignant, ready collaboration with oncologists and radiation oncologists improves outcomes. In fact, regardless of the type of surgery, the ability to bring together experts in neurosurgery, neurology, neuroradiology, physiatry, pain management, neuropathology, oncology and orthopedics is a key advantage.

So is the ability of a high-volume, academic medical center to conduct clinical research. Kliot and his colleagues have begun a project to understand why some peripheral nerve tumors continue to grow while others stop, often in the same patient. Another avenue of active research looks at procedures to fuse damaged axons, rather than relying on their regenerative capacity.

He expects such projects will lead to new treatments for repair of peripheral nerves, noting, "It's a very exciting time to be a peripheral nerve surgeon."

For more information, contact Dr. Michel Kliot at (415) 353-7500.


Neurosciences — Summer 2012 Index

Related Information

News Releases

How Selective Hearing Works
The longstanding mystery of how selective hearing works — how people can tune in to a single speaker while tuning out their crowded, noisy environs — was solved by two scientists from UCSF, and others at hospitals in the U.S., Canada and Europe. UCSF neurosurgeon Dr. Edward Chang and postdoctoral fellow Nima Mesgarani worked with three patients who were undergoing brain surgery for severe epilepsy.

Donors Support Neurosciences Research and Patient Care
UCSF received a challenge gift of $20 million from the Sandler Foundation that will support for the university's groundbreaking research and clinical care in neurological diseases. In honor of Herbert and Marion Sandler and the Sandler Foundation, the new neurosciences building at the UCSF Mission Bay campus will be named the Sandler Neurosciences Center.