Extraocular Muscle Enlargement and Proptosis Associated with Chronic Inflammatory Demyelinating Polyradiculoneuropathy.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an inflammatory neuropathy, which commonly causes peripheral neuropathy. It has rarely been associated with cranial nerve hypertrophy and neuro-ophthalmic manifestations. Proptosis secondary to cranial nerve hypertrophy has been reported in association with CIDP. The authors present a case of a 67-year-old man with CIDP who presented with bilateral proptosis, strabismus, and episodes of globe subluxation. The proptosis was mainly attributed to significant enlargement of the extraocular muscles, in addition to bilateral enlargement of the trigeminal nerves. There has been no published case of CIDP with associated enlargement of extraocular muscles without a history of underlying hyperthyroidism, inflammation, or malignancy. This may represent a new clinical finding in CIDP and adds to the limited literature on the neuro-ophthalmic and orbital associations of CIDP. The proptosis was managed with an uncomplicated bilateral orbital decompression.