Stevens-Johnson syndrome is a rare, intense sensitivity reaction to bacterial or viral infections and drugs (especially, but not limited to sulfa drugs). In some cases the cause may not be apparent. When the disease involves the eyes causing blisters of the surface eye tissues it can result in scarring and erosions of the corneas and blood vessel ingrowth.. This process can also permanently damage the inside of the lids causing the margins to become rough and sprout abnormal fine lashes that rub against the cornea. Because the cornea is the most sensitive tissue of the body, the pain and sensitivity can be intense and further aggravated by the dryness that results from damaged tear and oil glands that are critical to maintaining the lubrication of the eye.

 

The most serious long-term damage is the result of the destruction of corneal stem cells. These are the “maternal” cells that “give birth” to new corneal surface when they are necessary to replace those lost due to normal “wear and tear” or injury. Because adult stem cells do not multiply and therefore cannot be replaced, destruction of its stem cells compromises the corneas’ healing ability. Depending on the extent of the loss, the consequences can range from unapparent to the development of persistent surface erosions, scarring, the ingrowth of abnormal blood vessels and ulcers—all of which degrade vision..

 

The management of the long-term eye complications of this disease is designed to protect the corneal surface from injury due to drying and the friction of blinking. The copious use of artificial tears provides transitory relief. Frequent removal of in-turning lashes, scraping the rough covering that form over the inner lid margins and lid surgery designed to evert the lid margins or cover them with mucous membrane tissue can be helpful. Because of their incomplete healing, corneal transplants are rarely performed except as an emergency to seal perforations. There is an exception: Corneal transplants can survive following successful stem cell transplant surgery. However, stem cell transplants may not “take” and when they do, it is necessary to continue to take anti-suppression drugs into the indefinite future to prevent their being rejected.

 

The role of the Boston Scleral Lens

This device offers a new dimension to the long-term management of the eye complications of Stevens-Johnson syndrome. By creating a cushion of oxygenated artificial tears over the surface of the cornea, it provides a unique protective environment that mitigates the pain and photosensitivity and encourages healing of the corneal surface. Moreover, the smooth surface of the liquid reservoir masks the irregular surface of the cornea to improve vision.

 

The fitting process requires the design of the device to be adapted to the shape of the individual eye. Because of the scarring and adhesions that are typical of this disease, fitting SJS eyes is especially challenging and the procedure usually requires the fabrication of numerous lenses and up to three weeks (sometimes longer) for completion.

 

Can the Boston Scleral Lens help you?

This device does not replace the function of the lost corneal stem cells and therefore cannot reverse the corneal scarring or vascular ingrowth. It does offer three potential benefits:

1. Reduced pain and photosensitivity.
2. Improved vision.
3. Aids the healing of corneal erosions/ulcers and prevents their recurrence.

 

Improvement of vision is contingent on there being some relatively clear areas in or near the center of the cornea. If the central cornea is densely scarred or is covered by a thick layer of blood vessels, it is unlikely that your vision can be significantly enhanced. In this case, the Boston Scleral Lens would be indicated only if you experience chronic pain and photosensitivity that compromises the quality of your life. Your ophthalmologist/cornea specialist will determine if you are a candidate for this device. Please be aware that we do not accept patients without a referral.

 

Should your eye specialist feel that you may benefit from this modality, we will ask him/her to send the clinical information necessary for us to assess the advisability of your scheduling a consultation appointment. In the end, the decision to proceed with the fitting is dependent on the response of your eyes to trial of wearing a diagnostic lenses. This evaluation process takes one to three days.

 

 

Other corneal stem cell disorders

The above comments generally apply to other corneal stem cell diseases including: chemical injuries, thermal burns, ocular pemphigoid and aniridia.