Smartphone ophthalmoscope as a tool in teaching direct ophthalmoscopy: a crossover randomized controlled trial

Figures & data

Figure 1. Smartphone ophthalmoscope.

Note: A. Light-emitting diode in close proximity to the camera lens on the smartphone as almost co-axial illumination. B. USB cable with a corresponding connector (Type-C, Micro and Lightning from left to right). C. Screen capture of the camera app (Ullman Indirect) in the smartphone.

Figure 2. Study design.

Figure 3. Trainings of ophthalmoscopy using smartphone ophthalmoscopes.

Note: Demonstration and practice using the smartphone ophthalmoscope on patients in the darkroom (A). Fundus image captured with smartphone ophthalmoscope on patients with undilated (B) and dilated (C) pupils. Written informed consents had been obtained for the image to be published.

Figure 4. Students using ophthalmoscopes to visualize the fundus of the eye model.

Note: A and B. Visualizing the fundus of eye model using smartphone ophthalmoscope. C. Image captured using the smartphone ophthalmoscope. D. Visualizing the fundus of eye model using a direct ophthalmoscope.

Table 1. Baseline characteristics of the study population. Data presented as means ± SD or numbers.

	Group A (n = 24)	Group B (n = 21)	Total (n = 45)	P*
Age: years	21.3 ± 0.64	21.1 ± 0.83	21.2 ± 0.73	0.283
Gender: male	11	10	21	0.571
female	13	11	24

*Inter-group comparison of age (Mann-Whitney U test) and gender distribution (chi-square test).

Table 2. Objective assessment of ophthalmoscopy.

Source		Mean	F	P
Ophthalmoscope	1: Direct ophthalmoscope (DO)	4.71	46.918	<0.001
	2: Smartphone ophthalmoscope (SO)	8.42
Period	1: The first training session	6.13	1.348	0.249
	2: The second training session	7.00
Sequence	1: DO training first and then SO training	6.02	4.766	0.032
	2: SO training first and then DO training	7.19

Results of ANOVA for crossover design, comparing the skill of ophthalmoscopy using direct ophthalmoscope (DO) and smartphone ophthalmoscope (SO). Effect of sequence and the period.

Figure 5. Subjective assessment of ophthalmoscopy using DO and SO .

Note: Number of students who provided a rating from 1 to 5

Table

Statements	Direct ophthalmoscope	Smartphone ophthalmoscope
I can easily follow the teacher’s description about the working principle during didactic lecture.	1 2 3 4 5	1 2 3 4 5
I felt it easy to master the operating protocol.	1 2 3 4 5	1 2 3 4 5
I felt confident using the ophthalmoscope for ophthalmoscopy.	1 2 3 4 5	1 2 3 4 5
I am able to teach fellow students to use the ophthalmoscope	1 2 3 4 5	1 2 3 4 5
I think the ophthalmoscope helpful for non-ophthalmologists	1 2 3 4 5	1 2 3 4 5
I expect popularization of the ophthalmoscope among non-ophthalmologists in clinical practice	1 2 3 4 5	1 2 3 4 5
I found it uncomfortable to use the ophthalmoscope at its working distance	1 2 3 4 5	1 2 3 4 5

Data availability statement

All data analyzed or generated during the study are available from the corresponding author on reasonable request.