Delayed myelopathy following lightning strike: a demyelinating process.

Although the clinical findings in over 30 cases of delayed myelopathy after electrical injury have been described, there are scanty reports of the pathology of the spinal cord in such cases. We report a case in which progressive myelopathy presented 1 month after electrical injury by lightning strike and death occurred 4 months after injury. The spinal cord showed widespread demyelination of white matter from the medulla to just above the conus medullaris. This consisted of selective degeneration of myelin sheaths without inflammation or injury to axons, other cord components, or nerve roots. Infarction of more circumscribed segments of the thoracic cord where demyelination was greatest was probably due to edema associated with myelin degeneration, causing cord swelling limited by the pia mater. Raised pressure within the cord then resulted in secondary infarction.