Association between corneal sensitivity and Parkinson’s disease severity stages.

Abstract

Purpose : To evaluate the association between corneal sensitivity (CS) using a Non-Contact Brill Engines Esthesiometer and Parkinson’s disease (PD) severity.

Methods : A retrospective and observational study was performed in a national reference center for neurological diseases between August 1, 2023 and October 31, 2023. All patients were evaluated by a neuro-ophthalmologist and a movement disorders neurologist. Corneal mechanical sensitivity was assessed with the Brill Engines Esthesiometer, a non-contact esthesiometer that uses air-jet stimulation. Corneal mechanical sensitivity was assessed by applying increasing stimuli, three measurements for each level of intensity were taken and the average was recorded. Movement Disorders Society-Unified Parkinson’s disease rating scale Part III (MDS-UPDRS III) was used to assess the severity of motor symptoms and the Hoehn and Yahr (HY) stage scale to evaluate the severity of PD. Kruskal–Wallis test was used to investigate the association between CS and disease severity. A 95% confidence level was considered statistically significant.

Results : A total of 74 patients (148 eyes) were included. The patients’ mean age was 64.43±12.07 years, and 54.1% were male. The mean disease duration was 9.04±5.98 years. The mean MDS-UPDRS III was 31.14±12.92 points. The median CS was 6.5 mBar. The median CS in HY stage 1 was 8.33 mBar, HY stage 2 was 6.0 mBar, HY stage 3 was 7.08 mBar, and HY stage 4 was 10.25 mBar. HY stage 4 showed higher CS than lower stages HY 2 and 3, (p<0.001 and p=0.003 respectively). (Figure 1) No statistical difference was seen between other stages or clinical characteristics.

Conclusions : A reduced corneal sensitivity measured with a noncontact esthesiometer was associated with Parkinson's disease severity. CS could be considered a non-invasive and simple test to identify patients with severe stages of PD.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.

 

Figure 1. Corneal sensitivity in different stages of Parkinson's disease