Fundus photography with a smartphone in indirect ophthalmoscopy in dogs and cats

Abstract

Objective: To introduce a simple method for fundus photography of dogs and cats using a smartphone and indirect ophthalmoscopy lenses.

Methods: Fundus photographs of dogs and cats with transparent ocular media were obtained with 15D, 20D, 28D, and 40D indirect lenses and an iPhone-6, in a dark room and after pharmacologic pupil dilation. The photographs were recorded as still images using a video application and a video-to-still image application. Two types of neutral density (ND) filters were used as required for reduction of the torch illumination power of the iPhone.

Results: The images obtained in this study were upside-down as a result of the optics used. A 180-degree rotation was used to show their natural anatomical orientation. The image field of view varied with the diopter strength of the indirect lens used. The 40-diopter lens offered the widest field.

Conclusion: Still images obtained with a smartphone, and indirect lenses may be useful for client communication and teaching in small animal ophthalmology.

Keywords: cats; dogs; fundus; iPhone; indirect ophthalmoscopy; smartphone.