Influence of Specialty Contact Lens Wear on Posterior Corneal Tomography in Keratoconus Subjects.

OBJECTIVE: To evaluate the effect of specialty contact lens (CL) wear on posterior corneal tomography in keratoconus subjects. METHODS: Patients with keratoconus who were wearing specialty CL were included in this retrospective cohort study. Tomographic parameters were evaluated with Scheimpflug imaging (Pentacam HR) before lens fitting and immediately after removal of CLs worn habitually for a period of several months. Subjects were divided into groups, according to type of lens (corneal, scleral, and hybrid) and keratoconus severity based on Belin/Ambrosio D (BAD-D) score, for further analysis. RESULTS: Thirty-four eyes of 34 subjects diagnosed with keratoconus were included. Mean duration of habitual CL wear was 7.0±0.3 months. For the entire cohort, a small increase in flat keratometric reading at the anterior corneal surface (K1F; P =0.032) and at the posterior surface (K1B; P =0.041) was found. In the corneal CL group (10 eyes; 29.4%), flattening of the anterior corneal curvature was detected (K max ; P =0.015). An increase in K1B value was seen in the scleral CL group (15 eyes; 44.1%) ( P =0.03). Combined topometric indices showed a small but significant difference in the entire cohort ( P <0.05) and in the subgroups of corneal CL wear and of moderate keratoconus (BAD-D score≥7). CONCLUSION: Various types of specialty CLs exert a differential influence on corneal parameters. A small steepening of keratometry at the posterior surface (K1B) was observed in the scleral lens group. Although corneal lens wear flattens the anterior cornea (K max ), it does not significantly alter the posterior corneal surface.

A Case of Late Spontaneous Post-Radial Keratotomy Corneal Perforation Managed With Specialty Lenses.

PURPOSE: To describe a case of spontaneous wound dehiscence 29 years after radial keratotomy (RK) and to illustrate how specialty contact lenses were used for tectonic support and optic correction. SETTING: Tertiary referral center for corneal pathology. DESIGN: Case report. RESULTS: In November 2014, a 62-year-old woman presented to the emergency department with a spontaneous corneal perforation in her left eye. Her ocular history was significant only for uncomplicated RK surgery performed in 1985 to correct myopia (-5.50 D) in both eyes. At the slit-lamp pronounced, bullous edema was seen in the inferotemporal quadrant of the left cornea with internal opening of the 3.30- and 5-o'clock positions incisions and severe localized thinning and aqueous leakage at the 5-o'clock position incision. There was no history of trauma. A conservative approach was adopted: application of a standard bandage lens was effective in tamponading the leakage, allowing the anterior chamber to reform; a custom-made soft lens was worn for tectonic support over a period of 4 months. Finally, visual acuity was restored to 20/20-by fitting a scleral lens. CONCLUSION: Spontaneous corneal perforation is a rare but more dramatic long-term complication after RK. The pivotal role of appropriately fitted soft bandage lenses in the conservative management of this type of complex perforation is highlighted. For optical correction, a scleral lens was fitted with excellent visual result, illustrating the added value of specialty contact lenses as an alternative to surgery in the management of postrefractive corneas.

Scleral Lenses Reduce the Need for Corneal Transplants in Severe Keratoconus.

PURPOSE: To investigate the success and failure rates of scleral lens correction in severe keratoconus. DESIGN: Retrospective case series. METHODS: Study population comprised patients with keratoconus who attended the keratoconus clinic at the Antwerp University Hospital, Belgium, between January 1, 2010, and December 31, 2014. The included eyes had maximal keratometry values ≥ 70 diopters, as measured using the sagittal curvature map that was obtained by Scheimpflug tomography. The exclusion criteria included amblyopia, mental retardation, and concomitant ocular disease that limited their visual potential. RESULTS: Scleral lens fitting was proposed for the 75 eyes included in the study. Eight eyes underwent transplant surgery because of insufficient visual acuity with the lenses, lens intolerance, and issues with handling the lenses. Twelve eyes did not have lenses fitted because of good visual acuity in the other eye or a contraindication for lens wear. Three eyes were successfully fitted with corneal or hybrid lens wear. Scleral lenses were prescribed in 51 of 75 eyes. The mean gain in visual acuity (lens vs spectacle-corrected visual acuity) was 0.54 ± 0.18 (decimal fraction, Snellen eye chart). Seven eyes were lost to follow-up, 4 eyes abandoned wearing the scleral lens because of an inability to handle the lenses, and 40 eyes wore the lenses at their last follow-up visit, with a mean follow-up interval of 30.15 ± 12.83 months. CONCLUSIONS: Forty of the 51 eyes with severe keratoconus that would otherwise have undergone transplant surgery were successfully treated with long-term scleral lens wear. In this way, the indication for keratoplasty was more than halved in our keratoconus population.