Article

CLINICAL: RETINA

IMAGING THE PERIPHERY

Ultra-widefield imaging aids in the detection of retinal pathologies

A 37-year-old white male was referred by an optometrist for evaluation of a peripheral exudative retinal lesion OS. His BCVA was 20/20 OD and OS. Pupils, confrontation VF and ocular motilities were unremarkable OU. Dilated retinal examination OD was unremarkable. An exudative neurosensory detachment with retinal hemorrhage and an associated elevated fibrotic reddish lesion were observed in the inferior temporal peripheral retina OS.

Ultra-widefield (UWF) imaging captured the peripheral retinal changes, and the associated lesion was mildly elevated on B-scan ultrasonography. SD-OCT revealed an epiretinal membrane with associated increased retinal thickness of the macula. UWF fluorescein angiography showed retinal non-perfusion and vascular leakage of retinal pathology, and a hyperfluorescent lesion with ill-defined edges was also noted.

Visualization of the peripheral retina has become essential in the early detection, management and treatment of a number of vision-threatening retinal diseases, including diabetic retinopathy, retinal vascular occlusions, uveitis, retinal breaks and detachments. However, conventional fundus imaging modalities are restricted to the central 30° to 60° field of view of the retina. UWF imaging provides a rapid and efficient method of capturing 200˚ (82%) of the retina in a single image, and it is an excellent tool in detecting peripheral retinal pathologies. Also, there is a growing consensus in the medical literature that UWF imaging not only improves detection, but leads to a more accurate classification of the retinal disease.

Here, we discuss the importance of UWF imaging for various retinal conditions, this patient’s diagnosis (What do you think this patient had?) and how he was managed.

Note the exudative neurosensory detachment with retinal hemorrhage and an associated elevated fibrotic reddish lesion in the inferior temporal peripheral retina OS.
Courtesy of Dianna Shechtman, O.D., F.A.A.O.

DIABETIC RETINOPATHY DETECTION

The increasing incidence of diabetes in the U.S. ensures that diabetic retinopathy (DR) will continue to be one of the major threats to sight in adults. Therefore, assessing the peripheral retina in diabetic patients is critical in detecting DR.

Evaluating the peripheral retina with UWF imaging may substantially improve rates of DR detection, better characterize DR severity and more accurately define the risk of DR progression, according to Retina. Specifically, the presence of predominantly peripheral diabetic lesions, classified as microaneurysms, hemorrhages, venous beading, intraretinal microvascular abnormalities or neovascularization is predictive of a threefold increased risk of DR progression and a nearly fivefold increased risk of developing proliferative DR, reveals a prospective study conducted by researchers at the Joslin Diabetes Center and published in Ophthalmology.

In fact, about 51% of the patients who did not have proliferative disease at baseline were observed to have peripheral diabetic lesions with UWF, and 39% of these patients had DR progression. Thus, assessing the peripheral retina in diabetic patients may also help to identify a subset of patients at higher risk for progression, reports the American Journal of Ophthalmology.

Similarly, patients with peripheral retinal ischemia, non-perfusion or neovascularization, observed on UWF fluorescein angiography had a 3.75 time higher chance of developing DME compared to patients without retinal ischemia, reports Ophthalmology.

RETINAL VASCULAR OCCLUSION

Similar to DR, there is a direct correlation between peripheral non-perfusion and macular edema in retinal vascular occlusion (RVO), based on UWF imaging. In fact, in a study of patients with RVO and recurrent macular edema, the extent of peripheral non-perfusion was related to the degree of macular edema, reveals Retina. Thus, UWF imaging has prognostic value in RVO.

Peripheral non-perfusion or ischemia in RVO is valuable in determining the clinical course of the disease and response to anti-VEGF injection treatment. For example, patients with greater peripheral non-perfusion are more likely to have larger improvements in both macular thickness and VA following anti-VEGF therapy, reports Clinical Ophthalmology.

LEARNING POINTS

→ Detecting peripheral pathology is essential in the early diagnosis, management and treatment of a number of vision-threatening retinal conditions.

→ Conventional imaging may not detect all potential peripheral retinal pathologies.

→ Peripheral retinal lesions are predictive of increased risk for disease progression in diabetic retinopathy.

PERIPHERAL RETINAL VASCULAR ABNORMALITIES

UWF imaging is important to identify and manage a number of retinal vascular abnormalities ranging from sickle cell retinopathy, retinal vasculitis from inflammatory diseases and congenital disorders, such as familial exudative vitreoretinopathy retinal hemangiomas and other vascular tumors.

THAT PATIENT

Thanks to UWF imaging, the patient mentioned above was diagnosed with a vaso-proliferative tumor, an uncommon benign, unilateral retinal vascular mass that can appear in isolation or associated with other conditions, including Coats’ disease. OM