OCT Angiography Can Identify Early Diabetic Retinopathy

Laird Harrison

November 12, 2016

ANAHEIM, California — Optical coherence tomography (OCT) angiography can reveal the microaneurysms that are the first signs of diabetic retinopathy, new research shows.

If these microaneurysms are detected, optometrists could counsel patients to better control their diabetes to prevent vision loss, said Jessica Steen, OD, from the Nova Southeastern University College of Optometry in Fort Lauderdale, Florida.

"I truly believe that this is pertinent and that OCT angiography is going to be part of our management of diabetic patients," Dr Steen told Medscape Medical News.

OCT angiography uses motion contrast imaging, and takes advantage of blood flow to visualize retinal and choroidal vasculature, including retinal capillaries, in high-resolution detail.

It is less invasive than fundus fluorescein angiography because no injection of dye is required.

To see if OCT angiography could be used to detect early signs of diabetic retinopathy, Dr Steen imaged three women 62 to 68 years of with type 2 diabetes. The patients had had diabetes for 16 to 32 years, and the clinical level of diabetic retinopathy ranged from none to proliferative.

After clinical examination, she used 3×3 Zeiss AngioPlex OCT angiography centered at the fovea, and overlaid superficial OCT angiography images on fundus photographs.

Dr Steen presented the results of her research here at the American Academy of Optometry 2016.

Possible microaneurysms appeared as round, hyper-reflective, focal outpouchings of retinal capillaries. When she used fundus photography on the same patients, Dr Steen could not detect the microaneurysms, and she did not find them during clinical examination.

However, there are at least three challenges when this approach is used to detect diabetic retinopathy, said Dr Steen. First, motion artifacts remain significant. Current techniques cannot prevent patients from moving their eyes enough to distort the images and cannot compensate for these motions.

Second, Dr Steen acknowledged that she has had trouble repeating the findings.

And third, the 3×3 scan area centered on the fovea leaves a lot of the retina unexamined. "The general trend in diabetic retinopathy is peripheral changes," she said. "That's something that many companies are aware of and they are working on larger areas."

Currently, the software provided with OCT angiography scanners does not identify microaneurysms. When such software becomes available, it could make the devices more useful in detecting diabetic retinopathy, Dr Steen noted.

Innovative Work

During her work in a primary care clinic, Dr Steen said she sometimes detects advanced signs of diabetic retinopathy in her patients and refers them to primary care physicians.

The technique appears to be very promising, said David Sterna, OD, an optometrist from Lorain, Ohio. "Dr Steen has done some excellent, really innovative work," he added.

He said he is already seeing signs of diabetic retinopathy when he examines the eyes of some patients who don't know they have diabetes because they have not experienced any symptoms.

He sometimes provides finger-stick tests to confirm the diagnosis, he explained.

Dr Steen and Dr Sterna have disclosed no relevant financial relationships.

American Academy of Optometry (AAOpt) 2016: Abstract 165156. Presented November 10, 2016.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.