Allergy can affect corneal shape

BEER-SHEBA, Israel — Patients with vernal keratoconjunctivitis show more abnormalities on corneal topography than normal patients, according to a study. The abnormalities include an increase in corneal steepening in VKC patients, the study found.

Corneal topography may help clinicians decide how best to manage the disease, the study authors suggest.

Ruth Lapid-Gortzak, MD, and colleagues here at Soroka University Medical Center examined 40 patients with vernal keratoconjunctivitis (VKC) and 36 control subjects, comparing EyeSys videokeratography, numerical corneal indices and spherical equivalent refraction.

The patterns of corneal topography were abnormal in nearly 71% of the VKC group compared with 40% of the control group. Maximal corneal power was significantly higher in the VKC group compared with the control group as well.

Pediatric patients with vernal keratoconjunctivitis had a “statistically significant increase in keratoconus patterns” over control patients, according to the study.

Patients with VKC had significantly more abnormal corneal videokeratography patterns, higher maximal corneal dioptric power and increased superior-to-inferior asymmetry, with a trend to more superior corneal steepening. Nine eyes with VKC had keratoconus; none of the eyes in the control group did. Thirteen more eyes in the VKC group had patterns with a topographic trend to keratoconus, as compared to five eyes of five patients in the control group.

Superior steepening patterns were found to be common in VKC patients, although superior keratoconus is considered rare.

The study is published in the November issue of Ophthalmology.