Smartphone-based ophthalmoscope allows better, more accurate diagnoses
Nonophthalmologists deliver a better and more accurate fundus examination when using a smartphone-based alternative than with a direct ophthalmoscope, according to a recent study.
In the study, 20 final-year medical students each performed two fundal examinations on the eyes of 10 mannequins featuring five unique images. One was using a direct ophthalmoscope and the other was using the D-EYE, a clip-on, smartphone-based retinal imaging system which in the study was used with an Apple iPhone 5S device. A total of 200 examinations were conducted.
Using validated, objective questionnaires, researchers then scored each participant a maximum of three points per test for each correct clinical description, such that the highest total score for each image was 60. Students were then asked to deliver a diagnosis and rate their level of certainty.
Participants’ scores were significantly higher using the D-EYE vs direct ophthalmoscope when describing dry age-related macular degeneration (78 percent vs 47 percent; p<0.05). The same was true for the e3 of clinical descriptions of central retinal vein occlusion (52 percent vs 25 percent; p<0.05) and preproliferative diabetic retinopathy (72 percent vs 53 percent; p<0.05). [Eye 2018;32:1766-1771]
In comparison, scores trended toward significance in favour of D-EYE for the evaluation of optic atrophy (83 percent vs 57 percent; p=0.08), while no difference was observed for the accurate description of papilloedema (47 percent vs 48 percent; p=0.52). Moreover, the detection of a swollen optic disc likewise did not significantly differ between groups (60 percent vs 50 percent; p=0.26).
“We postulate that as the direct ophthalmoscope is able to provide a good quality image of the centrally located optic disc with a highly magnified view, the D-EYE does not offer any advantages for this diagnosis,” researchers explained.
In terms of delivering a correct diagnosis, D-EYE demonstrated significantly superior efficacy to direct ophthalmoscopy only for dry age-related macular degeneration (75 percent vs 30 percent; p<0.05).
A statistically comparable percentage of students were able to correctly identify central retinal vein occlusion (40 percent vs 30 percent; p=0.48), papilloedema (30 percent vs 30 percent; p=0.78), optic atrophy (20 percent vs 20 percent; p=0.66) and preproliferative diabetic retinopathy (70 percent vs 40 percent; p=0.10) using D-EYE or a direct ophthalmoscope, respectively.
“[T]he reason that students were able to less frequently make a correct diagnosis of papilloedema could have been due to the presence of hypertensive retinopathy and central retinal vein occlusion, which featured as alternative options in the questionnaire and are also associated with optic disc swelling,” said researchers.
The D-EYE system employed in the study produces images using co-axial illumination and a beam splitter. It works with an in-phone application that allowed the students to capture and store both photos and videos, which were available for playback as necessary.
As with any mobile-based technology, the drawbacks of the D-EYE revolve mostly around the need for a power source and security concerns regarding patient privacy and safe data transfer. However, the advantages may be too great to ignore.
“The ability to perform smartphone-based ophthalmoscopy could potentially allow for fundus images to be stored to the medical record for future comparison. Clinicians could use the digitally stored images to obtain a specialist opinion without arranging for a clinic visit,” researchers said.
“The use of smartphone-based technology in medicine and healthcare is rapidly evolving. The authors of this study feel that it may not be long before smartphone fundal imaging technologies are able to replace the direct ophthalmoscope in clinical medicine,” they added.