The preproliferative stage in type 2 macular telangiectasia (MacTel type 2)

Skeleton density and ellipsoid zone loss are prognostic for progression in Macular Telangiectasia Type 2

Macular Telangiectasia Type 2 (MacTel) is a chronic, progressive disease of the central retina characterized by vascular and neurodegenerative changes. As there is currently no treatment for non-neovascular MacTel, there is a dearth for biomarkers identifying eyes with an increased risk for disease progression for patient counseling and clinical trial recruitment. Eyes were classified to be stable or progressive, defined by the fundus photography-based grading system by Gass and Blodi. First, structural differences between these two groups were assessed, employing optical coherence tomography (OCT) and OCT-angiography. Univariate regression analyses revealed evidence towards a lower superficial retinal layer (SRL) vessel density (VD), skeleton density (SD) and deep retinal layer (DRL) SD in progressing compared to stable eyes (p = 0.05, p = 0.05, p = 0.07). Second, a multivariable predictive model was employed to examine the predictive value of structural and functional parameters for disease progression. Baseline best corrected visual acuity (BCVA) and SRL SD are prognostic for disease progression (p < 0.001, p = 0.05). The presence of ellipsoid zone (EZ) loss is prognostic for future central retinal thickness (p < 0.01). We propose SRL SD, BCVA, and EZ loss as prognostic biomarkers and as possible outcome measures in future interventional studies in MacTel.

Proximal nailfold videocapillaroscopy findings of patients with idiopathic macular telangiectasia type 2

PURPOSE

Idiopathic macular telangiectasia type 2 (IMT) is a neurodegenerative disease characterized by bilateral, idiopathic, and perifoveal retinal telangiectatic vessel formations. We aimed to compare proximal nailfold videocapillaroscopy (NV) findings between patients with IMT and healthy individuals and evaluate the optical coherence tomography angiography (OCTA) parameters of the patients with IMT according to their NV findings.

METHODS

The study included 43 patients with IMT and 92 healthy controls of similar age and gender without any additional diseases. The OCTA and NV findings of the patients and controls were examined.

RESULTS

The mean age was 59.76 ± 5.73 years in the IMT group and 58.23 ± 4.96 years in the control group. Of the 43 patients with IMT, 19 were found to have increased capillary tortuosity, six had microhemorrhage, and 18 had bizarre capillaries (P < 0.001). In the IMT group, the total vascular density value of the superficial capillary plexus was higher among the patients with capillary microhemorrhage (P = 0.001), and the subfoveal choroidal thickness was lower among those with increased capillary tortuosity and bizarre capillaries (P = 0.04 and P = 0.07, respectively).

CONCLUSION

This is the first study in which the NV findings of patients with IMT were compared with those of a control group. We found higher rates of increased capillary tortuosity, microhemorrhage, and bizarre capillaries in the IMT group compared to the controls. We consider that this situation is caused by microvascular damage. We also think that IMT is a systemic disease that affects both proximal nailfold capillaries and eye vessels.

Macular Telangiectasia Type 2: A Comprehensive Review

Macular telangiectasia Type 2 (MacTel) is a gradually progressive disease that affects the quality of life by impairing both distant and near vision. It had previously been considered a vascular condition, but recent evidence suggests a neurodegenerative etiology, with primary involvement of Muller cells. Retinal pigment epithelium (RPE) hyperplasia and subretinal neovascularization (SNV) are responsible for most of the vision loss in advanced cases. Neurotrophic factors in the non-proliferative phase and intravitreal anti-Vascular Endothelial growth factor (VEGF) in the proliferative phase have shown to retard the progression of the disease. This review will discuss the pathophysiology, clinical features, important diagnostic imaging studies and available treatment options for MacTel.