Early-stage macular telangiectasia type 2 vascular abnormalities are associated with interdigitation zone disruption

Purpose To investigate the relationship between disruption in different photoreceptor layers and deep capillary plexus (DCP) telangiectasias in eyes with macular telangiectasia type 2 (MacTel). Methods 35 eyes (21 patients) with MacTel imaged with optical coherence tomography angiography (OCTA) were included. Circumscribed areas of DCP telangiectasia were traced from OCTA slabs and the corresponding spectral-domain OCT (SD-OCT) slabs were used to visualize the photoreceptor layer interdigitation zone (IZ) and ellipsoid zone (EZ). IZ attenuation, IZ loss, and EZ loss were graded by reviewing en face SD-OCT slabs for hypo-reflective areas and confirming their status on cross-sectional views. Total area of photoreceptor disruption and overlap with DCP telangiectasia were evaluated with respect to OCT-based MacTel stage. Longitudinal changes were evaluated in a subset of patients with follow-up imaging. Results Overlap of DCP telangiectasia with IZ attenuation significantly decreased with MacTel severity, while overlap with IZ and EZ loss significantly increased. Overlap with IZ loss peaked in moderate MacTel (Stages 3–5). Longitudinal imaging showed that new EZ loss at 6 months was largely predicted by baseline IZ loss. Conclusions Worsening MacTel severity is characterized by greater overlap between DCP telangiectasia and zones of increasing severity of photoreceptor disruption, with EZ loss enlarging over time within areas of preexisting IZ disruption. We suggest that IZ disruption may indicate early photoreceptor dysfunction that eventually progresses to EZ loss, with IZ loss being a more reliable metric than IZ attenuation. Additional studies will be necessary to further explore long-term photoreceptor changes and evaluate their relationship with visual function in MacTel.

CRYSTALLINE RETINOPATHY WITH PERIFOVEAL TELANGIECTASIA – A CASE REPORT

We report a case of Macular Telangiectasia type 2 with crystalline retinopathy in a 42 year old female complaining of gradual decrease of vision in both eyes for the past one year. Both eye fundus showed perifoveal refractile crystals with lamellar macular holes. A diagnosis of crystalline retinopathy was made. Other causes of crystals were ruled out based on history, systemic examination, multimodal imaging & laboratory work-up. Presence of dilated perifoveal deep capillary plexus, foveal cavitation & temporal leakage on FFA conrmed association with Macular Telangiectasia. To our knowledge, there is no thorough documentation of crystalline reti-nopathy reported in Indian population.

Long-term Clinical Course of Korean Patients Diagnosed with Macular Telangiectasia Type 2

Purpose: To evaluate long-term visual prognosis and changes in the retinal microstructure in patients with macular telangiectasia type 2.Methods: Retrospective analysis of medical records were performed for 61 eyes (32 patients) diagnosed with macular telangiectasia type 2. The visual acuity at diagnosis was compared with that at the final visit. In addition, cases were classified into three grades based on optical coherence tomography (OCT) findings: grade 1, inner retinal cavities only; grade 2, outer retinal cavities with ellipsoid zone disruption; and grade 3, ellipsoid zone disruption with proliferation of retinal pigment epithelium. Change in the grade during the follow-up was verified. In addition, visual acuities were compared between eyes with and without a change in grade.Results: The mean follow-up period was 41.5 ± 33.2 months. Visual acuity had deteriorated significantly from the mean logarithm of the minimal angle of resolution 0.23 ± 0.26 at diagnosis to a mean of 0.31 ± 0.31 at the final visit (p < 0.001). When classified using OCT, 65.6%, 22.9%, and 11.5% were grades 1, 2, and 3, respectively, at diagnosis and 47.5%, 36.1%, and 16.4% at the final visit. Progression of grade was noted in 22.9%. A higher degree of visual deterioration was noted in eyes showing progression than in eyes without (p = 0.002).Conclusions: During the long-term follow-up period, visual deterioration was noted in patients with macular telangiectasia type 2. However, the degree of deterioration was not high. Progression in the disruption of the retinal microstructure was the likely cause of visual deterioration.