Map Dot Dystrophy
Corneal map-dot-fingerprint dystrophy is by far the most common corneal dystrophy. Map-dot-fingerprint dystrophy also is known as epithelial basement membrane dystrophy, anterior basement membrane dystrophy and Cogan microcystic epithelial dystrophy. It usually is classified as a dystrophy but fits more accurately into the corneal degeneration category.
Corneal dystrophies usually are hereditary, bilateral, progressive, and not associated with systemic or local disease. Map-dot-fingerprint dystrophy has been found in several families with a presumed autosomal dominant pattern, but in most cases it is not familial. It is not progressive but rather variable and fluctuating in its course. Usually, it is bilateral but can be unilateral or very asymmetric in presentation.
The corneal epithelium (or surface cells) normally is adherent to the underlying tissue. Corneal abnormalities associated with map-dot-fingerprint dystrophy are the result of faulty tissue connections, in which the surface cells are poorly adherent to the underlying tissue. This causes irregular looking epithelium, and in some patients painful recurrent erosions (abrasions) or decreased vision can occur. Fortunately, most patients are asymptomatic.
In the US, estimates of the prevalence of map-dot-fingerprint dystrophy range from 2-43% of the general population. Of patients with map-dot-fingerprint dystrophy, 10-33% have recurrent corneal erosions. This condition is slightly more common in females than in males. This condition is uncommon in children
There are many ways to treat this condition. Often, no treatment is needed. When used, therapy usually begins with certain lubricants or medicines including artificial tears, lubricating gels or ointments. Sometimes antibiotics and anti-inflammatory (steroid) drops are also used. A hypertonic solution called Muro 128 drops or ointment is commonly used to help repair the damaged adhesion molecules. This is a salt-based medicine, which helps make the surface cells more adherent to the underlying tissue. In certain patients, a bandage-type contact lens or patch may be used. In patients who have recurrent erosions, which are not responding to use of medicines and lubricants alone, a minor procedure performed in the office may be recommended. These include a superficial keratectomy (gentle smoothing to remove the damaged surface cells), stromal puncture (placement of small punctures in the surface of the eye to improve adhesion) or in some patients a laser resurfacing procedure.
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