A novel prosthetic device (Boston Scleral Lens) is custom-designed to vault the cornea over an oxygenated reservoir of artificial tears. It is designed to correct corneal first surface aberrations and address symptoms of dry eye disease.
Boston-The unique design features of a novel prosthetic device (Boston Scleral Lens, Boston Foundation for Sight) make it an effective option for correction of corneal first surface aberrations and management of dry eye symptoms in post-LASIK eyes, even those that are intolerant of contact lenses, said Deborah S. Jacobs, MD.
After fitting of the device, improvement in best-corrected visual acuity was achieved in all eyes, and the mean change for the group was –0.31 logMar units, which was highly statistically significant. Analyses of data from a baseline and follow-up National Eye Institute Visual Functioning Questionnaire 25 test, which was added to the new patient evaluations in 2006, demonstrated a significant improvement in visual function post-prosthesis fitting.
"Currently, there is limited awareness of this device, as well as limited accessibility, since patients must travel to Massachusetts for fitting. However, we are working to address these issues by publishing and presenting our experience, and we also hope to be opening satellite facilities in Texas and California by the end of 2008," she added.
When the prosthesis is being inserted, its reservoir is filled with artificial tears. The fluid is retained under the device vault when it is on the eye and acts to create an expanded pre-corneal tear film, serve as a liquid bandage, and mask irregular astigmatism.
Commenting on some of the features of post-LASIK eyes fitted with the prosthesis, Dr. Jacobs rhetorically raised the question of whether a high recent referral rate reflects late presentation of ectasia. She rejected that notion, however, and proposed instead that there may be a referral lag in the generally contact lens-intolerant group, members of which may be considering and delaying surgical options.
"As these eyes may not have their vision corrected with a contact lens, the patients and their doctors may continue to consider surgery. However, there may also be a misperception that the [device] is just another kind of conventional contact lens. Patients [whose eyes may not have responded to] contact lenses before or after LASIK may be inappropriately excluded by their ophthalmologist as a candidate for the [prosthesis]," Dr. Jacobs said.
Of the 75 eyes that were fitted with the device, 71%-including all eyes with aberrations as their primary indication for fitting-had undergone LASIK between 1998 and 2000.
"This may reflect a tendency to perform more aggressive treatments during that time frame, perhaps with more enhancements and/or less appreciation for LASIK exclusion criteria," she said.