Information for Ophthalmologists

MPS I can affect many different organ systems and patients typically see several specialists before getting a diagnosis. Because eye involvement occurs in all MPS I patients, referral to an ophthalmologist is likely. Below are presenting symptoms encountered by opthalmologists that may lead to clinical suspicion of MPS I and warrant more definitive testing.

Corneal clouding

Corneal clouding occurs in all MPS I patients, in some cases as early as the first year of life, and can lead to significant visual disability, especially in dim light. The condition, which has a “ground-glass” appearance, is caused by storage of glycosaminoglycans (GAGs) in the clear layers of the cornea.

Corneal CloudingCredit: Courtesy of J.E. Wraith

Retinal degeneration

Retinal degeneration associated with loss of peripheral vision and night-blindness may occur and can be assessed by an electroretinogram. Visual disturbances can progress to blindness from a combination of retinal pigmentary degeneration, optic nerve compression and atrophy, and cortical damage. Open-angle glaucoma is also a common complication.[2], [6]

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