A cyclic vertical deviation with dysthyroid ophthalmopathy: a case report.

Area of Science:

• Ophthalmology
• Neurology
• Endocrinology

Background:

• Cyclic strabismus is an exceptionally rare disorder of ocular motility.
• Characterized by alternating strabismus and orthotropia, it presents unique diagnostic challenges.
• Dysthyroid ophthalmopathy is a common cause of extraocular muscle abnormalities.

Observation:

• A 40-year-old woman with a history of hyperthyroidism presented with sudden onset vertical double vision.
• Computed tomography revealed asymmetric enlargement of the inferior and medial rectus muscles in the left eye, consistent with dysthyroid ophthalmopathy.
• The patient reported a distinct every-other-day pattern of diplopia, switching around 8 PM nightly, with significant left hypotropia on affected days.

Findings:

• The patient exhibited a 48-hour cycle of vertical deviation.
• The cyclic vertical deviation associated with dysthyroid ophthalmopathy resolved spontaneously.
• This case demonstrates a unique presentation of a rare ocular motility disorder.

Implications:

• Cyclic vertical deviations may resolve spontaneously as the underlying condition, such as dysthyroid ophthalmopathy, improves.
• Understanding the natural history of cyclic strabismus is crucial for patient management.
• This case underscores the importance of considering underlying systemic diseases in the etiology of intermittent strabismus.