Article Date: 3/1/2009

Succeeding With Ultra-widefield Imaging

Succeeding With Ultra-widefield Imaging

Learn how this new technology helps in an extensive array of retinal cases.

BY THOMAS R. FRIBERG, MD, MS, FACS

I have made some surprising discoveries while using the Ultra-Widefield Optomap-Plus Medical Retinal Exam and Optomap FA Angiography Procedure (Optos Inc., Marlborough, Mass.). But equally important are the cases in which I was able to confirm suspected pathology by using widefield imaging. Here, I will share some of my experiences with this technology to demonstrate its value in clinical practice.

DETECTING A DETACHMENT

One patient at our center had an abnormality in the periphery that was difficult to view and characterize with traditional imaging. Ultra-widefield fluorescein angiography revealed that the region was actually an area of retinal neovascularization associated with a small, chronic and local retinal detachment.

In another case, a veterinarian with symptomatic floaters presented with marked asteroid hyalosis.1 An Optomap image showed — quite remarkably — how the condition obscured his retina, causing a reduction in his visual acuity. This image (Figure 1) was most instructive for educating the patient. He opted for vitreous surgery. The vitrectomy successfully alleviated his blurriness and made it easier for him to perform surgery again.

Figure 1. Widefield imaging shows all of the asteroid particles in focus, and we can see the fovea is virtually obscured in the eye.

DIAGNOSING VASCULAR DISEASE

When we look only at the macula, we often overlook the presence of peripheral vasculopathies. For example, an Optomap FA fluorescein angiogram of a branch vein occlusion is very telling, because the wide-angle study shows that the pathology extends way out into the periphery. Essentially, this view enhances our understanding of the implications of such an occlusion.

Another issue: As retinal specialists, we see many pigmented retinal and choroidal lesions. We follow many of them for growth, particularly when we want to rule out a melanoma.2 With widefield imaging, I do not have to spend a great deal of time drawing the retina to document the lesion, and I can easily incorporate the images into our electronic records system. Because this instrument improves our ability to study diabetes, we can look beyond diabetic macular edema and better categorize and understand the disease by examining all of the retinal vessels.

We had one patient with some hemorrhaging, showing neovascularization and tremendous capillary dropout. The wider view (Figure 2) delineated the extent of the disease and helped me decide if I should photocoagulate out into the healthy retina or simply treat the areas of ischemia. Another patient had a few small laser spots and macular edema. The wide view allowed me to see some extensive peripheral capillary dropout that otherwise could have gone undetected.

Figure 2. A wider view delineated the extent of the disease in this patient with hemorrhaging, neovascularization and capillary dropout.

Also, if I have a patient with vitreous hemorrhaging (Figure 3), often I can still obtain an Optos image. This improves our ability to monitor the patient's progress when surgery is not immediately indicated.

Figure 3. Even in patients with vitreous hemmorhaging, often you can obtain widefield images.

INADEQUATE CONVENTIONAL IMAGING

Case #1: During a 2-month period, the vision of a 55-year-old healthy attorney's left eye decreased to 20/50+1 while his right eye remained at 20/20. Visual fields, MRI, slit lamp and fundus exams, performed by a resident, produced normal findings during a neuro-ophthalmology work-up. Biomicroscopy showed macular edema OS, confirmed through fluorescein angiography and optical coherence tomography (OCT).

Laboratory tests — RPR, FTA-ABS, CBC, sedimentation rate and rheumatoid factor — all came back negative. However, I found a retinal break in the periphery. Widefield angiography allowed me to document peripheral vascular leakage, which ultimately required photocoagulation treatment (Figure 4). This case demonstrates the value of detecting pathology that otherwise might be missed without widefield imaging.

Figure 4. Widefield angiography allowed the documentation of peripheral retinal ischemia and inflammation present in this eye.

Case #2: A doctor referred a young ballet dancer to me who had decreased vision in her right eye. Conventional fluorescein angiography showed a typical, late-stage petaloid pattern in the fovea, revealing no vascular abnormalities. I found many telangiectatic vessels in the periphery, in addition to cystoid macular edema (Figure 5) by using widefield angiography. In the left eye, I found a very small area of focal retinitis. I could not have seen these pathologies using conventional angiography.

Figure 5. Widefield angiography revealed cystoid macular edema and telangiectatic vessels in the periphery of this patient.

UNCOVERING MYSTERIES

As suggested by these cases, this machine has changed the way I practice. Usually, we approach angiography as a mundane necessity. Now, I perform the procedure much more enthusiastically, because I know the findings may be surprising. The technology provides me with almost every type of angiography I might need, including closer looks at macular disorders or macular edema, while also helping me document peripheral disorders as well. RP


Dr. Friberg is a professor in the departments of ophthalmology and bioengineering at the University of Pittsburgh and is the director of the retinal service at the Eye Center at the University of Pittsburgh Medical Center.

References
  1. Win PH, Young TA. Optos Panoramic200A fluorescein angiography for proliferative diabetic retinopathy with asteroid hyalosis. Semin Ophthalmol. 2007;22:67-69.
  2. Lee DS, Anderson SF, Perez EM, Townsend JC. Amelanotic choroidal nevus and melanoma: cytology, tumor size, and pigmentation as prognostic indicators. Optom Vis Sci. 2001;78:483-491.


Retinal Physician, Issue: March 2009