Tendon-Sparing Extraocular Muscle Enlargement Associated With Chronic Inflammatory Demyelinating Polyradiculoneuropathy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an inflammatory, sensorimotor polyneuropathy. It has presented with a variety of orbital and neuro-ophthalmic manifestations, including cranial nerve hypertrophy and a single case of extraocular muscle enlargement. The authors present a second case of tendon-sparing, extraocular muscle enlargement, resulting in new-onset diplopia and strabismus in a teenager with CIDP. The workup ruled out alternative causes of extraocular muscle enlargement, such as hyperthyroidism, inflammation, or malignancy. As with other cases of CIDP, management involved a combination of immunoglobulin therapy and anti-inflammatory medications. The patient experienced resolution of his symptoms, and radiologic improvement was noted in the muscle enlargement. As many CIDP patients have a favorable treatment response and long-term prognosis, awareness of this rare disease with an early and accurate diagnosis is important.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an acquired, immune-mediated sensorimotor polyneuropathy that presents to ophthalmologists with ophthalmoplegia, proptosis, papilledema, optic neuropathy, and pupillary abnormalities associated with cranial nerve hypertrophy.¹ The authors present a case of diplopia and esotropia with tendon-sparing extraocular muscle (EOM) enlargement in a teenager with CIDP.

CIDP is characterized by symmetric, progressive, or relapsing proximal and distal muscle weakness with peripheral sensory loss.¹ Clinical examination, nerve conduction studies, lumbar puncture, MRI, and nerve biopsy are used to make the diagnosis.² CIDP is highly responsive to treatment with immunosuppressants or immunomodulation, making early diagnosis important.³

Only one other case of CIDP-associated EOM enlargement has been reported, and this was in a 67-year-old man treated with decompression surgery.³ To date, this is the first report of CIDP-associated EOM enlargement in a pediatric patient successfully managed without surgical intervention. This report adhered to the ethical principles outlined in the Declaration of Helsinki as amended in 2013 and is compliant with the Health Insurance Portability and Accountability Act.

From: Ophthalmic Plastic and Reconstructive Surgery - © 2023 The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc.