Smartphone-Based Test May Help Detect Macula Abnormalities Early

A novel smartphone-based photostress recovery test (K-Photostress Recovery Test) may aid in detecting macular abnormalities earlier, according to a study published in Annals of Medicine and Surgery. The new testing modality is designed to be implemented easily into clinical ophthalmic practice.   

Researchers reviewed the smartphone-based test’s ability to examine macular functionality. The cross-sectional study included 48 visually impaired eyes (27 men, 21 women) and 47 normal-sighted age-matched control eyes (25 men, 22 women). The median age in participants with impairment was 71.0 years and the median age in normal participants was 70.0 years. 

At 5 cm distance perpendicular to the eye, a light produced by the smartphone (back) with an illuminance of approximately 4500 lumens/meters² filled the pupil for 10 seconds. The photostress recovery time was evaluated immediately after 10 seconds by asking the participants to read at least 3 letters on the visual acuity 1 line above the participant’s best visual acuity. The digital photostress testing was done with the best-corrected visual acuity (BCVA). 

Patients were assessed twice within 2 weeks for test-retest reliability. The investigators performed correlations among the recovery times, the visual acuity, and the contrast sensitivity functions as well correlations regarding each specific ocular disease. They analyzed correlations among technology, usability, and ease of performance in both groups. 

The recovery time in patients with impaired eyes was 83.5 (68.5, 126.0), while in the normal participants was 39.0 (14.0, 43.0). The median visual acuity in patients with impairment was 0.59 logMAR (0.40, 0.90), while in the normal participants was −0.06 logMAR. 

The test-retest reliability study involved 26 visually impaired eyes (16 men, 10 women) and 35 normal eyes (19 men, 16 women). The test-retest reliability analysis revealed a statistically significant correlation (P <.001) between test and retest in affected eyes and in normal eyes. The Intraclass Correlation Coefficients (with 95% confidence intervals) were also statistically significant (P <.001) among both groups.   

Recovery time in patients with diabetic retinopathy was statistically significantly lower than patients with dry age-related macular degeneration (P =.027) and patients with wet age-related macular degeneration (P =.032). The affected eyes had lower scores in technology, usability, and ease of performance compared with the normal eyes. 

Study limitations include that a large number of participants were discouraged from responding to the survey due to the COVID-19 lockdown, and further study is needed to standardize and validate this new testing modality.

Overall, the researchers “propose a new method for evaluating the response of the macula to photostress using a smartphone-based application.” They also believe that the application may help identify “abnormalities earlier, aiming to reduce visual impairment.” 

Reference

Karampatakis V, Almaliotis D, Papadopoulou EP, Almpanidou S. Design of a novel smartphone-based photostress recovery test for detecting abnormalities in the macula. A cross-sectional study. Ann Med Surg. Published online April 29, 2022.  doi:10.1016/j.amsu.2022.103699