Keratoconus Could Be Associated With Psoriasis: Novel Findings From a Comparative Study

To explore the relationship between keratoconus (KC) and psoriasis.

One hundred ten eyes of 55 patients with psoriasis (study group, SG) and 110 eyes of age-sex-matched 55 healthy volunteers (control group, CG) were included in the study. All cases underwent a detailed dermatological and ophthalmological examination including corneal topography. Moreover, Psoriasis Area and Severity Index (PASI) scoring of the patients was carried out in the SG. A thorough comparison of pachymetric, aberrometric, and topometric values between the groups was performed, and the results were interpreted. A χ test, Mann-Whitney U test, and Pearson correlation test were used for statistical assessment.

Although the average Kmax (44.6 in the SG; 44.5 in the CG; P = 0.613) and Belin/Ambrósio enhanced ectasia total deviation value (1.34 in SG; 1.20 in CG; P = 0.880) were similar between the groups, the mean index of vertical asymmetry value in the SG (0.14 mm) was significantly higher than that in the CG (0.11 mm) (P = 0.041). Moreover, 28 eyes from 16 patients with psoriasis were found to be associated with KC because 26 of those 28 eyes were KC suspects and 2 of them were definite KC. A positive correlation was found among topometric parameters, especially between duration of the disease and PASI score. A negative correlation was discovered between topometric parameters and the early beginning of psoriasis.

Serious changes in topography maps may occur in psoriatic patients. The changes were found to be more evident in the presence of a higher PASI score and the early beginning and longer duration of the disease. The results hinted a potential relationship between psoriasis and KC.