Diagnostic use of dermatomal somatosensory-evoked potentials in spinal disorders: Case series

• Published in: The journal of spinal cord medicine Vol. 36; no. 6; pp. 672 - 678
• Main Authors: Dikmen, Pinar Yalinay, Emre Oge, A.
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 01-11-2013; Maney Publishing
• Subjects: Adult; Arachnoid cysts; Dermatomal somatosensory-evoked potentials; Electromyography; Evoked Potentials, Somatosensory; Female; Humans; Male; Middle Aged; Multiple root involvement; Radiculopathy; Spinal Cord Diseases - diagnosis; Spinal Cord Diseases - physiopathology; Spinal cord lesions; Syringomyelia
• ISSN: 1079-0268; 2045-7723
• DOI: 10.1179/2045772313Y.0000000107

Objective/Context
Dermatomal somatosensory-evoked potentials (dSEPs) may be valuable for diagnostic purposes in selected cases with spinal disorders.
Design
Reports on cases with successful use of dSEPs.
Findings
Cases 1 and 2 had lesions causing multiple root involvement (upper to middle lumbar region in Case 1 and lower sacral region in Case 2). Cystic lesions in both cases seemed to compress more than one nerve root, and stimulation at the center of the involved dermatomes in dSEPs helped to reveal the functional abnormality. Cases 3 and 4 had lesions involving the spinal cord with or without nerve root impairment. In Case 3, an magnetic resonance imaging (MRI)-verified lesion seemed to occupy a considerable volume of the lower spinal cord, causing only very restricted clinical sensory and motor signs. In Case 4, a cervical MRI showed a small well-circumscribed intramedullary lesion at right C2 level. All neurophysiological investigations were normal in the latter two patients (motor, tibial, and median somatosensory-evoked potentials in Case 3, and electromyography in both) except for the dSEPs.
Conclusions
Objectifying the presence and degree of sensory involvement in spinal disorders may be helpful for establishing diagnoses and in therapeutic decision-making. Valuable information could be provided by dSEPs in selected patients with multiple root or spinal cord involvement.