Smartphone-based Anterior Segment Imaging: A Comparative Diagnostic Accuracy Study of a Potential Tool for Blindness Prevalence Surveys.

Abstract

PURPOSE:

To determine if smartphone photography could be a useful adjunct to blindness prevalence surveys by providing an accurate diagnosis of corneal opacity.

METHODS:

A total of 174 patients with infectious keratitis who had undergone corneal culturing over the past 5 years were enrolled in a diagnostic accuracy study at an eye hospital in South India. Both eyes had an ophthalmologist-performed slit lamp examination, followed by anterior segment photography with a handheld digital single lens reflex (SLR) camera and a smartphone camera coupled to an external attachment that provided magnification and illumination. The diagnostic accuracy of photography was assessed relative to slit lamp examination.

RESULTS:

In total, 90 of 174 enrolled participants had a corneal opacity in the cultured eye and no opacity in the contralateral eye, and did not have a penetrating keratoplasty or missing photographs. Relative to slit lamp examination, the sensitivity of corneal opacity diagnosis was 68% (95%CI 58-77%) using the smartphone's default settings and 59% (95%CI 49-69%) using the SLR, and the specificity was 97% (95%CI 93-100%) for the smartphone and 97% (95%CI 92-100%) for the SLR. The sensitivity of smartphone-based corneal opacity diagnosis was higher for larger scars (81% for opacities 2 mm in diameter or larger), more visually significant scars (100% for eyes with visual acuity worse than 20/400), and more recent scars (85% for eyes cultured in the past 12 months).

CONCLUSION:

The diagnostic performance of a smartphone coupled to an external attachment, while somewhat variable, demonstrated high specificity and high sensitivity for all but the smallest opacities.

• Authors: Ashish Kumar, Ferhina S Ali, Valerie M Stevens, Jason S Melo, N Venkatesh Prajna, Prajna Lalitha, Muthiah Srinivasan, Gopal Bhandari, Sadhan Bhandari, Robi N Maamari, Daniel A Fletcher, Thomas M Lietman, Jeremy D Keenan
• Journal: Ophthalmic epidemiology (Ophthalmic Epidemiol) Vol. 29 Issue 5 Pg. 491-498 (10 2022) ISSN: 1744-5086 [Electronic] England
• PMID: 34607500 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural)

Topics

• Blindness (diagnosis, epidemiology)
• Cicatrix
• Corneal Opacity
• Humans
• Prevalence
• Smartphone