Evaluation of corneal sensitivity in multiple sclerosis patients

To measure the corneal sensitivity in patients with multiple sclerosis (MS), to compare it with normal values and to study its correlation with different disease characteristics.

Corneal sensitivity of 28 MS patients was compared to corneal sensitivity of 28 age- and gender-matched normal controls. Corneal sensitivity was measured using the Cochet-Bonnet esthesiometer and was correlated to the duration, type and severity indexes of the disease.

Corneal sensitivity was comparable between both groups (P = 0.79). No statistically significant correlation was found between corneal sensitivity and the duration of MS (P = 0.55) nor the severity indexes of MS (expanded disability status scale [EDSS] P = 0.52, global multiple sclerosis severity score [MSSS] P = 0.64). Following subgroup analysis, only the primary progressive (PPMS) form of MS had a reduced corneal sensitivity with P = 0.023, while remittent-recurrent (RRMS), secondary progressive (SPMS), and clinically isolated (CIS) forms of MS did not have any reduction in the corneal sensitivity. "ROC curve analysis" showed an area under the curve of 0.48.

In the exception of PPMS subtype, MS patients have similar corneal sensitivity in comparison to controls. Cochet-Bonnet esthesiometer does not seem to be a good diagnostic tool or a disease severity marker for patients with MS.