Ashish Kumar1, Ferhina S Ali2, Valerie M Stevens3, Jason S Melo3, N Venkatesh Prajna1, Prajna Lalitha4, Muthiah Srinivasan1, Gopal Bhandari5, Sadhan Bhandari5, Robi N Maamari3,6, Daniel A Fletcher6, Thomas M Lietman2,3,7,8, Jeremy D Keenan2,3. 1. Department of Cornea and Refractive Surgery, Aravind Eye Hospital, Madurai, India. 2. Department of Ophthalmology, University of California, San Francisco, California, USA. 3. Francis I. Proctor Foundation, University of California, San Francisco, California, USA. 4. Department of Ocular Microbiology, Aravind Eye Hospital, Madurai, India. 5. Bharatpur Eye Hospital, Bharatpur, Nepal. 6. Department of Bioengineering and Biophysics Program, University of California, Berkeley, California, USA. 7. Department of Epidemiology & Biostatistics, University of California, San Francisco, USA. 8. Institute for Global Health, University of California, San Francisco, California, USA.
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.
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: S M McClintic; M Srinivasan; J Mascarenhas; D A Greninger; N R Acharya; T M Lietman; J D Keenan Journal: Eye (Lond) Date: 2012-12-14 Impact factor: 3.775
Authors: Seth R Flaxman; Rupert R A Bourne; Serge Resnikoff; Peter Ackland; Tasanee Braithwaite; Maria V Cicinelli; Aditi Das; Jost B Jonas; Jill Keeffe; John H Kempen; Janet Leasher; Hans Limburg; Kovin Naidoo; Konrad Pesudovs; Alex Silvester; Gretchen A Stevens; Nina Tahhan; Tien Y Wong; Hugh R Taylor Journal: Lancet Glob Health Date: 2017-10-11 Impact factor: 26.763
Authors: Robi N Maamari; Somsanguan Ausayakhun; Todd P Margolis; Daniel A Fletcher; Jeremy D Keenan Journal: JAMA Ophthalmol Date: 2014-07 Impact factor: 8.253
Authors: John M Nesemann; Marleny Muñoz; Sandra L Talero; Harvy A Honorio-Morales; Andres G Lescano; Jeremy D Keenan Journal: Trans R Soc Trop Med Hyg Date: 2022-06-01 Impact factor: 2.455