Quality and Diagnostic Utility of Mydriatic Fundus Plenoptic Photography: The Plenoptic Ophthalmoscopy Reliability Trial

Visualization of the ocular fundus is considered an essential part of the physical examination, as abnormalities of the optic nerve, retinal vessels, and macula can reveal underlying systemic diseases and explain the etiology of visual complaints.

The Fundus Photography versus Ophthalmoscopy Trials Outcomes in the Emergency Department (FOTO-ED) Study demonstrated that only 14% of patients with complaints and conditions in which fundus examination is considered important had direct ophthalmoscopy performed by an ED physician .Greater than 80% of previously unknown fundus findings relevant to ED patient management were missed by ED physicians, but were identified by nonmydriatic digital fundus photography. Several of these cases resulted in recall of a discharged patient back to the ED for hospital admission once diagnostic fundus photos were reviewed.

In the search for an alternative to improve ease of use and fundus image quality, plenoptic technology provides a promising option for portable fundus imaging. Plenoptic, or light field, imaging has recently been introduced commercially with the release of the Lytro Plenoptic Camera (Mountain View, CA, USA). Utilizing an array of microlenses, the Lytro camera captures all available light in a scene from multiple vectors. By dividing up a scene as a whole with many individual microlenses, images can be refocused in post processing after acquisition, sharp focus can be attained in low light situations, and stereo images with perspective shifting can be attained.

To date there have been no published quantitative descriptions of the quality and reliability of plenoptic ophthalmoscopy using a commercially available, portable light field camera. Initial work from a pilot study using animal and human eyes was published in 2016. The purpose of the proposed prospective, cross sectional imaging study is to compare standard mydriatic fundus photography to a second generation camera developed with a Lytro plenoptic camera and customized light source, specifically analyzing diagnostic utility/sensitivity of detecting retinal pathology and overall image quality. If the image quality outcomes of the investigators proposed study are similar to those of the nonmydriatic fundus camera, the implications for physicians and the potential applications to ophthalmology related telemedicine are significant.