Study examines concurrent keratoconus, corneal dystrophies

Cornea. 2009;28(2):127-135.

Study data on associations of keratoconus with corneal dystrophies may aid future research on pathophysiologic or genetic links underlying those conditions.

The study is believed to be the largest to date in the English literature on concomitant keratoconus and corneal dystrophy, the authors said.

"Although keratoconus and corneal dystrophies are infrequent in the general population, there are reported cases of both in the same eye," they said. "It is important to report the association of conditions with keratoconus even when rare because many of these combinations could be manifestations of common pathogenic mechanisms or may represent adjacent genetic defects, as has occurred with other diseases."

The study included 95 eyes of 51 patients who presented with concurrent keratoconus and corneal dystrophies. Mean patient age was 47.3 years.

Bilateral associations with keratoconus were seen in 44 patients (86.3%) and unilateral associations in seven patients (13.7%). The most common associations were Fuchs' dystrophy (27 cases, 52.9%), anterior basement membrane dystrophy (13 cases, 25.5%) and posterior polymorphous dystrophy (seven cases, 13.8%).

Data showed three cases of a bilateral combination of keratoconus, Fuchs' dystrophy and anterior basement membrane dystrophy. Results also showed one bilateral case of granular dystrophy.

Genetic analysis will advance understanding of the factors underlying the associations, the authors said.