Retinal (or fundus) photography is an essential part of any
ophthalmology practice. Commercial fundus cameras can cost tens to hundreds of
thousands of dollars, putting the technology out of reach for smaller ophthalmic
practices and to physicians in third-world countries.
In a recent study now on line, Massachusetts Eye and Ear
researchers describe the relatively simple technique of fundus photography in
human and rabbit eyes using a smartphone, an inexpensive app for the smartphone,
and instruments that are readily available in an ophthalmic practice.
Smartphones are now being used more routinely in
ophthalmology to document patients' ocular conditions, the authors write.
Previously described techniques of fundus imaging often proved difficult to
repeat, partly because video capture using Apple's built-in camera app in the
iPhones cannot independently control the focus and the exposure during filming,
which results in glare and poor image quality.
"Our technique provides a simpler and higher quality
method to more consistently produce excellent images of a patient's
fundus," said senior author Shizuo Mukai, MD, Mass. Eye and Ear retina
specialist and Harvard Medical School associate professor of Ophthalmology.
has been extremely helpful for us in the emergency department setting,
in-patient consultations, and during examinations under anaesthesia as it
provides a cheaper and portable option for high-quality fundus-image
acquisition for documentation and consultation. This technique is well
tolerated in awake patients, most likely since the light intensity used is often
well below that which is used in standard indirect ophthalmoscopy."
Using the described technique of smartphone fundus
photography with the use of iPhone 4 or iPhone 5, the app Filmic pro, and a 20D
lens with or without a Koeppe lens, researchers were was able to capture
excellent, high-quality fundus images in both children under anaesthesia and in
awake adults.The best results were achieved in the operating room when a
Koeppe lens was used in addition to the 20D lens; however, excellent images
were acquired with the 20D lens alone in the clinic and emergency room setting
as well as in the operating room. Researchers report that even first-year
ophthalmology residents were able to master this technique in a relatively
"This technique is relatively inexpensive and simple to
master, and takes advantage of the expanding mobile-telephone networks for
telemedicine," Dr Mukai said. "We expect that the quality of the
images achieved using this technique will continue to improve as
higher-resolution cameras with larger sensors and better image stabilisation is
incorporated into newer smartphones."
Picture: Smartphone from Shutterstock