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Published on: September 20, 2024
Enhance postoperative filtering bleb-induced vision difficulties with well-fitted GP contact (oxygen-permeable)
1University of California, Davis Medical Center, Department of Ophthalmology, Sacramento, California 95817, USA. kaaryn.pederson@ucdmc.ucdavis.edu
Background:
Occasionally contact lenses need to be fit on patients with filtering blebs. Gas-permeable (GP) lens fitting is still controversial because, although the contact lens can improve visual acuity and satisfy a patient's visual need, it can also compromise the bleb and increase the risk of ocular infection.
Methods:
A retrospective review of charts evaluated patients wearing a GP contact lens a minimum of two months after trabeculectomy surgery. Seven optometrists and one ophthalmologist submitted data on 20 eyes (15 subjects). Success of the contact lenses on these eyes was evaluated, as well as patient history and ocular complications from the contact lens. Contact lens success was based on the patient's ability to wear a GP contact lens a minimum of 6 hours a day, at least 4 days a week, without permanent damage or significant compromise to the bleb.
Results:
GP contact lenses were successfully fit and worn on 17 of 20 eyes with a functioning filtering bleb (85%). Two of the 17 eyes terminated GP contact lens use after a few years for reasons unrelated to contact lens wear. Three eyes (15%) were unsuccessful and discontinued GP contact lens wear. Of the three eyes that were not successful in wearing a GP contact lens, two eyes discontinued wear secondary to contact lens intolerance and one eye discontinued contact lens wear as a result of fitting difficulties. There were no complications of blebitis or endophthalmitis, but two eyes were treated for bleb laceration and staining of the bleb.
Conclusion:
GP contact lenses can be successfully worn in eyes with filtering blebs. However, to reduce the risk of complication and infection, proper fitting guidelines should be followed and patients should return for evaluations at intervals of 6 months or less.
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