Retinal Review, Issue 80
Danielle Strauss, MD - Retinal Review November 2018
A 57-year-old woman was referred to our office for decrease in vision OU. She was noted by the referring OD to have cataracts, as well as possible macular edema. She had a history of type 2 diabetes for 10 years, and her last HgbA1c was 8.5%. The OD was concerned she may have diabetic retinopathy with macular edema. She had no other medical issues.
Upon presentation, her BCVA was 20/30 OU, IOP was 19mgHg OD, and 18mmHg OS. Anterior segment exam was remarkable for 2+ NS cataracts OU.
Dilated funduscopic examination revealed, a sharp, pink nerve, some mild macular changes with blunted foveal reflexes, and a flat retina 360 OU. Here are the wide-field color fundus photos of each eye.
As you can see in the photos, there is no evidence of diabetic retinopathy, such as dot-blot hemorrhages, microaneurysms, or lipid deposition. There is no evidence of retinal ischemia either, and the retinal vessels appear unremarkable. To better evaluate the subtle macular changes evident on the DFE, an SD-OCT was performed, scanning through the maculae. Here are the results:
The SD-OCTs shows defect in the inner neurosensory retina symmetrically, temporal to the fovea.
A wide-field fluorescein angiogram was performed to further evaluate these changes (Note: these are images of the FA late phase).
Wide-field FA shows mild hyperfluorescence in temporal maculae ou. Again, there is no evidence of changes consistent with diabetic retinopathy. Here are magnified images of the FA of the maculae.
So what is the diagnosis in this case?
The imaging above is consistent with a disease known as macular telangiectasia type 2 (MacTel2).
MacTel2 is an idiopathic macular disorder characterized by alterations in the capillary network of the macula. This leads to neurosensory atrophy, typically temporal to the center of the fovea. MacTel2 effects men and women equally. The typical age range of patients with MacTel2 is 50-60 years-old. Dilated funduscopic examination will reveal blunting of the foveal reflex, or retinal “graying.” OCT of the fovea may show bilateral symmetric lamellar macular holes with temporal displacement. Rarely, MacTel2 can be associated with retinal neovascularization. FA is considered the gold standard for diagnosing MacTel2. Characteristic findings on FA are telangiectatic vessels in the temporal macula with late leakage and hyperfluorescence.
In terms of visual acuity, patients with MacTel2 may have slight visual reduction in the early stages of MacTel2. If the disease progresses, however, patients may lose central vision, or may have a paracentral scotoma on visual field testing. Even with advanced MacTel2, vision rarely falls to less than 20/200.
Unfortunately, there are no proven beneficial treatments for MacTel2. Photocoagulative laser, as well as photodynamic therapy have not been proven to be useful in stabilizing this disease. Similarly, intravitreal injections of steroid and anti-vegf agents have also not been proven to be beneficial. However, not all cases of MacTel progress to become atrophic with decline in visual acuity.
This patient will be monitored by the retina team biannually for progression of the disease.