Abstract
Purpose :
To determine the feasibility of using soft hydrogel contact lenses as non-invasive sources for dopamine measurements
Methods :
This pilot study included 20 patients, age 18-30 years old, with myopia -0.75D to -5.00D. Three different designs of soft hydrogel lenses (single vision spherical and dual focus in Omafilcon A and extended depth of focus in Etafilcon A) lenses were worn for an 8-hour period and then collected, initially in 1ml saline and then dry. The tear envelops containing the dopamine were extracted and these extracts analysed using a direct competitive chemiluminescent enzyme linked immunosorbent assay (ELISA) dopamine kit (ENZO Life Sciences UK)
Results :
Minimal variation was observed between the lens types in terms of the dopamine level recovered for analysis Omafilcon A 442.1±82.7pg/ml and Etafilcon A 455.1±67.7pg/ml (p=0.038)
Data, as would be expected due to the different sampling methods, is higher than a previously reported study using Schirmer strips and capillaries as shown in Table 1.
The assay method has sufficient sensitivity to detect dopamine in tear fluid (down to the pStep 1: Title/Bodyicogram/ml level as shown in Table 1).
Conclusions :
The findings demonstrate that a soft hydrogel contact lens can be used as a non-invasive sampling vehicle to remove the tear envelope and allow dopamine detection from the anterior ocular environment. Different lens types did not adversely affect the recovery rate from the tear envelop.
By combining different sampling methodologies this will enable a greater understanding of the diurnal and longitudinal variation in dopamine levels using both snapshot assessment via Schirmer strip, ophthalmic sponge or capillary tube and non-invasive tear envelop sampling. This will provide insights into the role of dopamine and other neurotransmitters to better understand factors involved in myopia progression.
This is a 2021 ARVO Annual Meeting abstract.