Determining Optic Nerve Cupping Using Optical Coherence Tomography (OCT) Versus a New Electronic Mobile Device

We present a new device that may aid in glaucoma screening. The vertical cup-to-disc ratio (CDR) obtained from a new electronic mobile device (EMD) was compared with that obtained from a spectral-domain optical coherence tomography. In addition, results from examiner's evaluations were compared with the results mentioned above.

A single-masked study was performed to evaluate the CDR results from 110 eyes from 110 subjects whose ages ranged between 18 and 60 years (39±13 y old), of whom 66 (60%) were female individuals. Vertical CDR was analyzed 5 times with each device in a single visit and evaluated by 3 different ophthalmologists. The Spearman correlation test and Bland-Altman analysis were used to evaluate the correlation and agreement between methods.

The CDR average using spectral-domain optical coherence tomography was 0.47±0.04, whereas the CDR average using EMD was 0.42±0.02. The clinical evaluation resulted in an average of 0.34±0.27. The Spearman test showed a strong correlation between vertical CDR obtained with both devices (r=0.8319; P<0.0001) and between EMD and the examiners (r=0.7156; P>0.001). Bland-Altman analysis showed good agreement between both devices as well as between EMD and the examiners (95% limits of agreement from -0.20 to 0.10 and from -0.15 to 0.30, respectively).

We present a low-cost, reliable EMD that may serve as an alternative to subjectively measuring vertical CDR in face-to-face consultations and hence increase the general public's access to glaucoma screening. This may be especially useful for patients who live in remote areas.