Variability between handheld fundus cameras
Reviewed by Nishita Patel

Handheld fundus cameras offer the potential of enhancing opportunities for telemedicine diagnosis of glaucoma, especially in underserved settings, as they are less bulky, inexpensive and don’t require skilled personnel compared to traditional table-mounted retinal cameras. This study aimed to compare the quality of optic nerve photographs from three different handheld fundus cameras and to assess the reproducibility and agreement of vertical cup-to-disk ratio (VCDR) measurements from each camera. For this cross-sectional study adult patients were recruited from an ophthalmology clinic and an intravitreous injection clinic in northern Thailand. Optic nerve photography was performed on 355 eyes with each of the three handheld cameras: the Volk iNview, Volk Pictor Plus, and Peek Retina. Images were graded for VCDR in a masked fashion by two photo-graders and images with >0.2 discrepancy in VCDR were assessed by a third photo grader. Optic nerve images were judged ungradable in 130 (37%) eyes imaged with Peek Retina, 36 (10%) eyes with iNview and 55 (15%) eyes with Pictor Plus. For 193 eyes with gradable images from all three cameras, inter-rater reliability for VCDR measurements was poor or moderate for each of the cameras, with intraclass correlation coefficients ranging from 0.41 to 0.52. A VCDR ≥0.6 was found in six eyes on iNview images, nine eyes on Pictor Plus images, and three eyes on Peek images, with poor agreement between cameras, showing variable performance for detecting clinically meaningful VCDRs. Limitations of the study were acknowledged and include a limited collection of clinical information relevant to glaucoma and a sample that is likely not representative given the study was conducted at only two clinics in Thailand.

Comparison of three handheld fundus cameras for assessment of the vertical cup-to-disk ratio.
Saroya J, Lu L, Ausayakhun S, et al.
OPHTHALMIC EPIDEMIOLOGY
2024;31:311–4.