Relevance of Multicolor Imaging in Type 2 Macular Telangiectasia

Abstract

Purpose: To report the imaging characteristics of various clinical features in idiopathic macular telangiectasia (MacTel 2) on multicolor imaging (MCI) and compare its accuracy vis-à-vis color fundus photograph (CFP) and fluorescein angiography (FA). Methods: In this retrospective observational study, 54 eyes of 27 patients with MacTel 2 were included after institutional review board approval. Multimodal imaging with CFP, optical coherence tomography (OCT), MCI, and FA was done. Images were analyzed to identify and describe the clinical findings in MacTel 2. Sensitivity, specificity, and positive and negative predictive values were computed for the various imaging modalities in MacTel 2. Results: In this study, the MCI identified all the different clinical features of MacTel 2 in 100% of cases. The confocal blue reflectance (BR) image was more sensitive than CFP (100% vs. 96.3%) in identifying the loss of retinal transparency in MacTel 2. For other clinical features such as right-angled vessels, superficial retinal crystals, and retinal pigment epithelial hyperplasia/plaques, the sensitivity of BR, and green reflectance (GR) image, was comparable to that of CFP. Confocal infrared reflectance (IR) images showed poor sensitivity in identifying the non-proliferative features in MacTel 2 (P < 0.001). Loss of retinal transparency was not picked up on IR image. Other features such as right-angled vessels, superficial retinal crystals, and pigment plaques were seen in 20%, 4.6%, and 26.3% of cases, respectively. However, confocal IR images were superior to FA (100% vs. 47%) and CFP (100% vs. 15%) in identifying the extent and location of subretinal neovascular membrane. The confocal BR and GR images were unable to identify the choroidal neovascular membrane (P < 0.001). Conclusion: MCI is a useful and non-invasive imaging modality to identify the clinical features in MacTel 2. MCI can be used as a complementary imaging tool to CFP, FA, and OCT.

Multi-color imaging in a unilateral central retinal artery occlusion following dengue fever: A case report and literature review

“…In this table, we summarized the observations of MCI and its advantages found in published papers. The list is not exhaustive; however, it highlights the salient features of different retinal and choroidal disorders [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38].…”

Functional relevance of macular telangiectasia (MacTel) area on multicolour imaging in type 2 MacTel

“…A few recently published papers on MC imaging in type 2 MacTel have already established its valuable role in the disease diagnosis and identifying the exact extent of involvement and disease stage including the advanced stage of SRNVM. 12,13,19 The confocal blue reflectance using the 488 nm short wavelength light demonstrates increased reflectance in the parafoveal region in eyes with type 2 MacTel. 6,20,21 The area of hyper reflectance is usually slightly larger than the area of hyper fluorescence in late-phase fluorescein angiography or increased hyper autofluorescence seen on FAF, providing evidence that the disease process extends beyond the margins of the angiographically visible vascular alterations.…”

“…1,6 In such scenarios, the confocal infrared reflectance images identify the retinal hyperpigmented plaques as dark spots and the SRNVM as a well-defined area of hyper reflectance within the area of retinal telangiectasia. 13 These reasons make the MC colour fundus image as an extremely valuable tool in the diagnosis, identifying the disease stage, accurately recognising the extent of involvement and finally for assessing progression at various follow-up visits.…”

“…The diagnosis was confirmed on the MC image based on the description provided in our previous publication on MC imaging in type 2 MacTel. 13 The confocal blue and green reflectance channels were used to identify the non-proliferative signs of type 2 MacTel like perifoveal greying and loss of retinal transparency, superficial retinal crystals and retinal pigment epithelial hyperplasia/plaques. Confocal infrared reflectance channel was used to identify the presence and extent of SRNVM.…”

“…A recently published paper by our group showed the MC imaging to be a useful non-invasive imaging technique to identify both early and late features in type 2 MacTel. 13 Features of the non-proliferative disease such as loss of retinal transparency, presence of superficial retinal crystals, right-angled vessels and retinal pigment epithelial plaques are identified on the blue and green reflectance channels. Presence of subretinal neovascular membrane suggestive of proliferative disease stage is noted on the infrared reflectance channel.…”