Multifocal motor neuropathy presenting as ophthalmoplegia

A 45-year-old man developed ophthalmoplegia and subsequently multiple cranial nerve palsies in association with bibrachial paresis. Investigations revealed evidence of conduction block occurring at a very proximal location (i.e., the spinal roots) and seemingly sparing sensory fibers. Other causes were ruled out and a diagnosis of multifocal motor neuropathy with conduction block (MMN) was suggested. The patient responded to cyclophosphamide. …