A Prospective Clinical Evaluation of a New Scleral Contact Lens for Patients with Distorted Corneas

Abstract

Objectives: A prospective clinical evaluation of the physiological fit and visual performance of a novel commercially available rigid gas permeable (RGP) scleral contact lens in subjects suffering from distorted corneas is described. Materials and methods:The physiological fit and visual performance of 23.5 mm and 21 mm RGP scleral contact lenses were assessed in 14 subjects (22 eyes) and nine subjects (12 eyes), respectively. All but one participant with a distorted cornea as a result of an infection, suffered from varying grades of keratoconus. In a subset of seven subjects (8 eyes), the higher order aberrations were measured with and without the scleral lenses. Results:The 23 mm RGP scleral lens improved visual performance in 82% of the participants and eight subjects were satisfied with the lenses. The 21 mm lens improved visual performance in 83% of the participants, and four subjects were satisfied with the lenses. Subjects that were satisfied with the lenses tended to lack other forms of visual correction. In the seven subjects that were included in the substudy, the total lower order, higher order, coma, and tetrafoil root mean square were significantly reduced (p df=7 < 0.05) with the scleral contact lenses, whereas the total trefoil was not. Conclusion:RGP scleral lenses can be comfortably worn for approximately 7 hours, improve visual acuity, and reduce higher order wavefront aberrations. The lenses can be fit easily by the practitioner, though a trial lens set is necessary. The lenses are recommended in cases where other forms of visual correction can no longer be tolerated and as a long-term or temporary alternative to corneal transplant.