Basics of EBMDEBMD is a disorder of the basal epithelial cells located in the front part of the cornea. These basal cells stick to the second membrane layer, also referred to as Bowman's layer. In EBMD, the basal cells create abnormal fingerlike projections that stick out from the thickened underlying membrane. These projections cause the epithelial cells to become loose and not stick as well to the membrane. Along with other changes that occur among the epithelial cells, these changes give an appearance of maps, dots and fingerprints within the cornea. These characteristic changes can be seen with the use of a slit lamp biomicroscope.
Symptoms of EBMDPeople with EBMD may complain of the following symptoms:
- fluctuating vision
- blurred vision
- intermittent pain
Symptoms tend be worse upon waking or during the morning hours because the eye dries out at night and the cells that are poorly adhered seem to come off more easily.
Diagnosis of EBMDEBMD is often missed by physicians as the corneal map, dot and fingerprint appearance that commonly develops with the condition can be subtle in many cases. However, upon close inspection, these characteristic changes can be detected. Eye doctors will listen closely to your symptoms and overall medical history which may give them clues. A special yellow dye may also be instilled into your eye to make subtle corneal surface changes more visible. Doctors may also perform keratometry or corneal topography which measure the overall shape of the cornea. Your tear film will also be studied under the microscope to rule out other conditions such as keratoconjunctivitis sicca and other subtle dry eye conditions.
Treatment of EBMDTreatment of EBMD in people who don't have apparent symptoms include using artificial tears several times per day to encourage optimal epithelial cell health. People with more noticeable symptoms will be told to make more frequent use of artificial tears, as well as bland eye ointments instilled before bedtime. If there is a history of dry eye, punctal occlusion is also recommended. Punctal occlusion involves inserting a small collagen or silicone plug in the tear drainage canal of the eye to conserve the patients tears. Blindfolds or goggles may also be part of the treatment plan to prevent dryness from occurring at night.
In moderately severe cases, doctors will recommend a hypertonic eye drop or ointment during the day and at night. A hypertonic solution is a salt solution that draws the fluid out of the cornea, making it very compact. This helps the epithelial cells stay more tightly adhered to the cornea. Occasionally, doctors will use soft contact lenses to smooth out the cornea.
In cases in which the patient develops recurrent corneal erosions, doctors will prescribe antibiotic drops. Cycloplegic drops may also be used to reduce pain and improve comfort. Cycloplegic drops calm the inflammation in the eye by temporarily paralyzing the muscle inside the eye that can contract strongly and cause pain. Cold compresses, chilled artificial tears and topical non-steroidal anti-inflammatory eye drops may also be prescribed.
What You Should Know About EBMDIf you don't respond well to medication, a procedure called anterior stromal puncture may be recommended. Anterior stromal puncture involves the doctor using a sterile needle to create small, deep punctures that cross the lower membrane. This causes small scars to form and speed healing, causing the overlying cells to stick to the membrane better. Another form of treatment is PTK. PTK, photorefractive therapeutic keratectomy, uses a laser to smooth out the surface of the cornea to reduce symptoms.
Primary Care of the Anterior Segment, Second Edition. Copyright 1995, Appleton & Lange.