Clinical validation of a smartphone-based handheld fundus camera for the evaluation of optic nerve head

Author(s)

Titoneli, Carolina C. ^[1] ; Filho, Marcio S. ^[2] ; Lencione, Diego ^[3] ; Vieira, Flavio Pascoal ^[3] ; Stuchi, Jose Augusto ^[3] ; Paula, Jayter S. ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Med Ribeirao Preto, Ribeirao Preto, SP - Brazil

^[2] Fundacao PIO XII, Barretos, SP - Brazil

^[3] Phelcom Technol, Sao Carlos, SP - Brazil

• Document type: Journal article
• Source: Arquivos Brasileiros de Oftalmologia; v. 84, n. 6, p. 531-537, 2021.
• Web of Science Citations: 0

Abstract

ABSTRACT Purpose: To compare the quality of retinal images captured with a smartphone-based, handheld fundus camera with that of retinal images captured with a commercial fundus camera and to analyze their agreement in determining the cup-to-disc ratio for a cohort of ophthalmological patients. Methods: A total of 50 patients from a secondary ophthalmic outpatient service center underwent a bilateral fundus examination under mydriasis with a smartphone-based, handheld fundus camera and with a commercial fundus camera (4 images/patient by each). Two experienced ophthalmologists evaluated all the fundus images and graded them on the Likert 1-5 scale for quality. Multivariate regression analyses was then performed to evaluate the factors associated with the image quality. Two masked ophthalmologists determined the vertical cup-to-disc ratio of each fundus image, and both the intraobserver (between devices) and interobserver agreement between them was calculated. Results: Ninety-eight images from 49 patients were processed in this study for their quality analysis. Ten images from five patients (four from commercial fundus camera and one from smartphone-based, handheld fundus camera) were not included in the analyses due to their extremely poor quality. The medians [interquartile interval] of the image quality were not significantly different between those from the smartphone-based, handheld fundus camera and from the commercial fundus camera (4 [4-5] versus 4 [3-4] respectively, p=0.06); however, both the images captured with the commercial fundus camera and the presence of media opacity presented a significant negative correlation with the image quality. Both the intraobserver [intraclass correlation coefficient (ICC)=0.82, p<0.001 and 0.83, p<0.001, for examiners 1 and 2, respectively] and interobserver (ICC=0.70, p=0.001 and 0.81; p<0.001, for smartphone-based handheld fundus camera and commercial fundus camera, respectively) agreements were excellent and statistically significant. Conclusions: Our results thus indicate that the smartphone-based, handheld fundus camera yields an image quality similar to that from a commercial fundus camera, with significant agreement in the cup-to-disc ratios between them. In addition to the good outcomes recorded, the smartphone-based, handheld fundus camera offers the advantages of portability and low-cost to serve as an alternative for fundus documentation for future telemedicine approaches in medical interventions. (AU)

• FAPESP's process: 16/00985-5 - Portable equipment for retina diagnosis controlled by smartphone
• Grantee: Flávio Pascoal Vieira
• Support Opportunities: Research Grants - Innovative Research in Small Business - PIPE