Case of the Month
Edited by Robert N. Johnson, MD
Case #118 April, 2019
Presented by Michelle Peng, MD
A 64-year-old woman with blurred vision following cataract surgery
Figure 1A: Color photo of right eye. Note the gray-whitish area at the temporal edge of the fovea and fine crystalline deposits.
Figure 1B: Color photo of left eye. Note the gray-whitish area at the temporal edge of the fovea, fine crystalline deposits and pigment hyperplasia.
A 64-year-old woman presented with persistently blurred vision in both eyes following uncomplicated cataract surgery.
On examination, visual acuity was 20/80 in the right eye and 20/50 in the left eye. Pupils were equal round and reactive with no afferent pupillary defect. The intraocular pressures and anterior segment were unremarkable. Fundus examination demonstrated blunted dilated venules, mildly ectatic capillaries, crystalline deposits, and retinal pigment epithelial hyperplasia in both eyes (Figure 1). Ocular coherence tomography (OCT) showed cystic cavitation, photoreceptor disruption, and outer retinal damage (Figure 2). OCT angiography demonstrated the telangiectatic capillaries particularly within the temporal macula (Figure 3). Early phase fluorescein angiography highlighted the irregularly dilated capillaries and revealed hyperfluorescence in late frames (Figure 4).
Figure 2A: SD-OCT of the right macula. Note the atrophy and disruption of the retinal layers at the temporal edge of the fovea and small areas of cavitation.
Figure 2B: SD-OCT of the left macula. Note the atrophy and disruption of the retinal layers at the temporal edge of the fovea and areas of inner retinal hyperreflectivity due to RPE hyperplasia seen on the color photo (Figure 1B)
Figure 3A: OCT-angiogram of the right macula. Note the telangiectatic vessels.
Figure 3B: OCT-angiogram of the left macula. Note the telangiectatic vessels and some capillary nonperfusion.
Figure 4A: Early arteriovenous phase fluorescein angiogram of th right macula. Telangiectatic vessels can be seen on the nasal side of the fovea, but early dye leakage is already obscuring the view temporally.
Figure 4B: Late phase fluorescein angiogram of the right macula. Note the dye leakage in the fovea.
What is your Diagnosis?
Crystalline retinopathies – Toxicity (Methoxyflurane, Nitrofurantoin, Tamoxifen, Ritonavir, Triamcinolone, Talc), Metabolic disorders (Secondary hyperoxaluria) Inherited diseases (Bietti’s, Cystinosis), Vascular diseases (Talc, Macular Telangiectasia), Idiopathic (Chronic retinal detachment)
Additional History and Diagnosis
The patient has a history of well-controlled Type II diabetes mellitus. She had no other past ocular history. Based on her clinical history and exam findings the patient was diagnosed with macular telangiectasia type IIA.
Macular telangiectasia type IIA is a clinical entity first described by Donald Gass as a bilateral, symmetric, paracentral capillary telangiectasia of unknown cause which develops in the fifth to sixth decade.1,2 More recent studies suggest that it is a primary neurodegenerative condition of blood vessels and Muller cells.3
The condition has five stages: Stage I has very minimal capillary dilation with little to no noted abnormalities. Stage 2 demonstrates slight graying of the parafoveolar retina but continues to have minimal telangiectatic changes. In stage 3 there is an increase in the number of blunted and dilated venules that extends into the parafoveolar retina at right angles. Stage 4 is characterized by the development of hyperplastic RPE which encircles the angular vessels. In stage 5 the parafoveal macula may develop subretinal neovascularization. Multiple small golden crystalline may be found in the inner retina in about half of patients.4,5
OCT typically demonstrates cystic cavities with variable disruption in retinal layers. These cavities tend to collapse leaving an area of atrophy. In later stages patients may present with a lamellar macular hole or reactive pigment hyperplasia.6,7 Early phase fluorescein angiography highlights the telangiectatic vessels. Diffuse hyperfluorescence is seen in late phases.8 Some patients may develop subretinal neovascularization which may lead to subretinal hemorrhage, disciform scar, or retinochoroidal hemorrhage. Loss of vision typically occurs slowly due to atrophy of the foveolar retina.2,4
Numerous treatment modalities have been tried but none appear to address non-neovascular macular telangiectasia.8,9 In cases of subretinal neovascularization anti-VEGF treatment may be used.10,11 A recent Phase II clinical trial of the ciliary neurotrophic factor implant showed decreased ellipsoid zone loss, the progression of disease.12
Take Home Points
Want to Subscribe to Case of the Month?
Comments or Questions