A Novel Telemedicine Device for Diagnosis of Corneal Abrasions and Ulcers in Resource-Poor Settings

Abstract

 

Purpose

 

Corneal ulcers are a significant cause of corneal blindness worldwide. Normally, corneal injury is diagnosed by an ophthalmologist via slit-lamp examination. However, limited healthcare resources and personnel in developing regions may delay diagnosis and treatment, and increase the risk of vision loss. In this study, we evaluate a modified mobile phone camera for diagnosis of corneal epithelial defects.

 

Methods

 

An ophthalmologist examined 17 eyes from an inpatient ophthalmology service for corneal epithelial defects. Diagnosis was made with slit-lamp and fluorescein. Before administration of fluorescein, corneal photographs were taken for all patients with an iPhone® 4S camera coupled to a custom attachment with a +25 diopter lens and white external light-emitting diode (LED) light source (Ocular CellScope, University of California, Berkeley). A photograph was also taken after administration of fluorescein using the same phone coupled to a +25 diopter lens, 550nm/50nm emission filter, and blue LED light source. Three offsite ophthalmologists, masked to the onsite diagnosis, graded all 34 photographs. We calculated the sensitivity and specificity of both types of photography assuming the onsite ophthalmologist as the gold standard.

 

Results

 

The onsite ophthalmologist detected an epithelial defect in 6 of 17 eyes. The sensitivity of remote diagnosis of an epithelial defect was higher for the fluorescein photographs (83.3%, 100%, 66.7%) than for the white light photographs (50% for all three graders), and specificity was similar (100%, 90.9%, and 100% for fluorescein photographs and 100% for all three graders for the white light photographs). There was weak evidence that the grades of the white light photographs were different from the onsite diagnosis (P=0.08 for each grader, McNemar’s test), but no evidence of this for the fluorescein photographs (P=0.32; 0.32; 0.15).

 

Conclusions

 

The novel modified iPhone camera shows potential as a new technology for diagnosis of corneal abrasions and ulcers. This technology—especially with the fluorescein attachment—could be useful for diagnosing corneal injury in resource-poor settings. Further testing with a larger sample size is necessary to validate this telemedicine device.

 

 

Ocular CellScope with fluorescein attachment

 

 

Image of a corneal ulcer taken with the Ocular CellScope

 

Keywords: 550 imaging/image analysis: clinical