[Evoked motor and sensory potentials in syringomyelia]

Area of Science:

• Neurology
• Neurophysiology

Background:

• Syringomyelia, a condition characterized by a fluid-filled cyst within the spinal cord, presents diagnostic challenges.
• Accurate diagnosis and assessment of spinal cord involvement are crucial for effective management.

Purpose of the Study:

• To evaluate the correlation between clinical, radiological (MRI), and electrophysiological findings in patients with syringomyelia.
• To determine the sensitivity and utility of various evoked potentials in detecting spinal cord dysfunction.

Main Methods:

• Diagnosis of syringomyelia was confirmed using MRI, assessing syrinx extension and diameter.
• Electrophysiological tests including posterior tibial somatosensory evoked potentials (PT SEP), median (M SEP), trigeminal (V3 SEP), brain stem auditory evoked potentials (BAEP), and motor evoked potentials (MEP) were performed.
• Results were correlated with clinical presentations and radiological data.

Main Results:

• Electrophysiological abnormalities, particularly MEPs (72%), were frequent, often without overt clinical deficits.
• Posterior tibial SEPs were more sensitive than median SEPs.
• Trigeminal SEPs showed higher sensitivity than BAEPs and detected dysfunction in 46.6% of high cervical syringomyelia cases.
• A positive correlation was observed between electrophysiological and radiological findings, especially with lateral clinical data.

Conclusions:

• Electrophysiological tests, particularly MEPs and trigeminal SEPs, are valuable for detecting subclinical spinal cord dysfunction in syringomyelia.
• Combining various SEP and MEP tests provides comprehensive assessment of spinal cord integrity.
• These tests correlate well with MRI findings, aiding in diagnosis and management.