Abstract
Purpose : Uncorrected refractive error such as myopia is a global healthcare burden. If detected early, it is a treatable condition, ultimately preventing amblyopia and reducing the risk of severe ocular complications. The inherent smartphone-camera-lens, with built-in flash presents as an affordable and convenient photorefraction device for large-scale vision screening programs. This study evaluated the application of smartphone photorefraction for pediatric vision screening compared against the autorefraction technique, before and after cycloplegia (pupil dilation).
Methods : A total of 141 Chinese schoolchildren (ages 7 to 14 years old) were recruited in this study. Participants’ refractive errors were measured by an optometrist using auto-refraction and the smartphone technique under non-cycloplegic (dry) and cycloplegic (wet) conditions. The smartphone camera was employed to capture eye images at different orientations by rotating the smartphone around four distinct meridians (at vertical 90o, oblique 45o/135o, and horizontal 180o orientations). Refractive error was calculated based on pupil diameter size and crescent image width using conventional theory-based approach. A cross comparison of the transcribed autorefractor reading with photorefraction results was made.
Results : The refractive error measured by autorefractor (ranging from +0.50 D to -12.00 D) were compared among photorefraction results along the four meridians. The correlation r were 0.88 and 0.80 for non-cycloplegic and cycloplegic photorefraction, respectively. The overall mean absolute error (MAE) was smaller under non-cycloplegic conditions (0.65 D vs. 0.84 D). In addition, for dry photorefraction, 79.2% fell within a MAE of +/- 1.00 D compared to 70% for wet photorefraction. Both methods demonstrated an overall sensitivity of >97% in estimating myopic values greater than -1.50 D while the specificity was higher in dry photorefraction (dry: 78% vs wet: 72%).
Conclusions : Our results suggest that smartphone photorefraction has good correlation with auto-refraction, particularly under non-cycloplegic condition. The smartphone method yields as reliable and sensitive measures to detect myopic refractive errors compared with the autorefraction, thereby offering a promising low-cost option for refractive error screenings in poverty-ridden areas of the world.
Methods : A total of 141 Chinese schoolchildren (ages 7 to 14 years old) were recruited in this study. Participants’ refractive errors were measured by an optometrist using auto-refraction and the smartphone technique under non-cycloplegic (dry) and cycloplegic (wet) conditions. The smartphone camera was employed to capture eye images at different orientations by rotating the smartphone around four distinct meridians (at vertical 90o, oblique 45o/135o, and horizontal 180o orientations). Refractive error was calculated based on pupil diameter size and crescent image width using conventional theory-based approach. A cross comparison of the transcribed autorefractor reading with photorefraction results was made.
Results : The refractive error measured by autorefractor (ranging from +0.50 D to -12.00 D) were compared among photorefraction results along the four meridians. The correlation r were 0.88 and 0.80 for non-cycloplegic and cycloplegic photorefraction, respectively. The overall mean absolute error (MAE) was smaller under non-cycloplegic conditions (0.65 D vs. 0.84 D). In addition, for dry photorefraction, 79.2% fell within a MAE of +/- 1.00 D compared to 70% for wet photorefraction. Both methods demonstrated an overall sensitivity of >97% in estimating myopic values greater than -1.50 D while the specificity was higher in dry photorefraction (dry: 78% vs wet: 72%).
Conclusions : Our results suggest that smartphone photorefraction has good correlation with auto-refraction, particularly under non-cycloplegic condition. The smartphone method yields as reliable and sensitive measures to detect myopic refractive errors compared with the autorefraction, thereby offering a promising low-cost option for refractive error screenings in poverty-ridden areas of the world.
| Original language | English |
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| Title of host publication | Investigative Ophthalmology & Visual Science |
| Pages | 2819 |
| Volume | 63 |
| ISBN (Electronic) | 1552-5783 |
| Publication status | Published - Jun 2022 |
| Event | Association for Research in Vision and Ophthalmology (ARVO) Annual Meeting 2022 - Denver, United States Duration: 1 May 2022 → 4 May 2022 |
Conference
| Conference | Association for Research in Vision and Ophthalmology (ARVO) Annual Meeting 2022 |
|---|---|
| Abbreviated title | ARVO 2022 |
| Country/Territory | United States |
| City | Denver |
| Period | 1/05/22 → 4/05/22 |