A case of classical ocular myasthenia gravis showed all of the diagnostic features of the Eaton-Lambert syndrome. Needle electromyographic study showed a myopathic pattern. The nerve conduction study documented mild peripheral neuropathy. Muscle biopsy showed increased sarcolemmal and internal nuclei, type II fiber atrophy, and "ragged red" fibers.
Despite the response of symptoms to parenterally administered edrophonium chloride and neostigmine bromide, there were minimal clinical and electrophysiologic responses with orally given pyridostigmine bromide and neostigmine. With guanidine there was 70% clinical improvement and normalization of electrophysiologic abnormalities. With combined medication with guanidine hydrochloride and orally administered pyridostigmine, there was short-lived 100% clinical improvement.
Oh SJ. The Eaton-Lambert Syndrome in Ocular Myasthenia Gravis. Arch Neurol. 1974;31(3):183–186. doi:10.1001/archneur.1974.00490390065006