Macular Corneal Dystrophy
is Uncommon but Can Cause Severe Vision Problems
Macular corneal dystrophy is one of many different types of corneal dystrophies. A corneal dystrophy is a bilateral (both eyes affected) condition that is inherited. Eyes with corneal dystrophy develop cloudiness or opacities of the cornea of the eye that can lead to pain or discomfort and often to blurred vision.
Macular corneal dystrophy is a bilateral cloudiness of the cornea along with opacities primarily in the central layer of the cornea, the stroma. Macular corneal dystrophy is the least common of all the corneal stromal dystrophies. However, it is also the most severe. Multiple gray to white colored deposits are seen in the central cornea that extend into the peripheral cornea. There is severe corneal haze throughout the entire stroma layer of the cornea. Macular corneal dystrophy is not an inflammatory condition. There are three types of macular corneal dystrophy based on the amount of immunoreactive keratin sulfate within the tissues. It is an inherited condition that is uncommon and is genetically autosomal recessive. This corneal dystrophy results in the earliest and usually the most severe vision loss of all corneal dystrophies.
Signs & Symptoms of Macular Corneal Dystrophy
The corneal changes usually become apparent under high magnification in the first decade of life and then get worse usually causing reduced vision before age forty. Patients become light sensitive and have eye pain from recurrent corneal erosions. Corneal guttata may also be present.
Treatment of Macular Corneal Dystrophy
Medical Care for Macular Corneal Dystrophy
Recurrent corneal erosions are treated with a bandage contact lens and antibiotics. After early healing of the corneal erosion preventive treatment consists of sodium chloride 5% drops (brand name Muro 128) and artificial tear lubricating drops (e.g. TheraTears or Soothe XP) during the day and sodium chloride 5% ointment (eg, Muro 128) at bedtime. The hypertonic salt medicine helps to secure the bond between the outer layer cells of the cornea (epithelium) and the underlying basement membrane layers to hopefully prevent recurrence of the recurrent corneal erosion.
Artificial tears should be used at least four times per day and sunglasses should be used to minimize the photophobia (light sensitivity).
Surgical Care for Macular Corneal Dystrophy
Substantial corneal erosions and a slight reduction in visual acuity can be treated with Phototherapeutic keratectomy (PTK) using an excimer laser. PTK usually only works well for very superficial opacities.
A severe reduction in visual acuity or large and deep opacities usually necessitate a corneal transplant. Even after a corneal transplant the corneal deposits can come back after time.