Faculty Bibliography

Three patients with hereditary motor sensory neuropathy type I developed neurologic deficits attributable to hypertrophic nerve roots. Compression of the cervical spinal cord by enlarged nerve roots occurred in our index patient. Multilevel decompressive laminectomies relieved the myelopathy. An unrelated patient who had syncope precipitated by neck rotation had hypertrophied nerve roots that eroded into the transverse foramina in juxtaposition to the vertebral arteries. In a 3rd patient, compression of hypertrophied nerve roots within the thecal sac and neural foramina was associated with spinal claudication and radiculopathy, respectively.

An unsuccessful attempt to terminate myoclonic status epilepticus with elevation of serum magnesium levels is described. During 3 days, serum magnesium was increased from 1.5 mEq/L to 14.2 mEq/L by continuous i.v. infusion of 3-6 g/h of magnesium sulfate. Other anticonvulsants were maintained at nearly constant levels. Cerebrospinal fluid magnesium was 3.5 mEq/L during the infusion. Despite magnesium-related neuromuscular blockade and accompanying cessation of visible myoclonus, the electroencephalogram revealed ongoing blunted sharp-wave activity at the baseline frequency. Transient complications of the infusion included prolongation of the PR interval on the electrocardiogram, hypomotility of the gastrointestinal tract, and peripheral muscle flaccidity, all of which resolved within 24 h of return to normal serum magnesium levels. These results suggest that the therapeutic role of magnesium in myoclonic status epilepticus is limited.

A 67-year-old woman developed a transient paraplegia as the initial manifestation of acute aortic dissection. Chest or abdominal pain was not present. Magnetic resonance imaging of the thorax demonstrated dissection of the aortic root, aortic arch, and descending aorta as well as pericardial effusion. Ultrasonography of the abdomen revealed an intimal flap in the region of the artery of Adamkiewicz. During aortic dissection, temporary obstruction of spinal arteries may result in transient paraplegia. Painless aortic dissection should be considered in patients who present with transient myelopathy.