Agreement between Time-Domain and Spectral-Domain Optical Coherence Tomography in the Assessment of Macular Thickness in Patients with Idiopathic Macular Telangiectasia Type 2

Abstract

Purpose: To estimate the conversion factors to transpose macular thickness measurements on time-domain (TD) to various spectral-domain (SD) optical coherence tomography (OCT) machines in patients with macular telangiectasia type 2a (MacTel). Procedures: Macular scans on TD- and SD-OCT were performed on patients at the same visit. The retinal thickness values in various ETDRS subfields and macular volume were compared between different OCT machines. Results: The macular thickness and volume were significantly greater (p < 0.0001, r = 0.678-0.822) on SD-OCT. The mean differences in macular thickness between TD Stratus and SD-OCT by Spectralis, Cirrus and Topcon were 62, 41 and 20 μm, respectively. The conversion factor of macular thickness from TD-OCT to Spectralis, Cirrus and Topcon were +65, +39 and +25 μm, respectively. Conclusion and Message: The estimates of conversion of macular thickness from TD- to SD-OCT using simple mean differences between machines and those by linear regression were similar suggesting that the former may be used for the longitudinal follow-up of MacTel patients.

Swept-Source OCT Angiography of Macular Telangiectasia Type 2

“…17 Optical coherence tomography (OCT), a noninvasive imaging modality, has revealed structural abnormalities in the inner retina such as retinal cavitation with draping of the internal limiting membrane and abnormalities in the outer retina such as disruption of the photoreceptor inner segment/outer segment/ ellipsoid (IS/OS/E) region that were not previously appreciated by FA or AF imaging. 3,[18][19][20][21][22][23][24][25] OCT imaging has improved the early detection of MacTel2 by identifying these early subtle changes in retinal anatomy, and OCT has proven to be useful for following these alterations in macular anatomy as the disease progresses to foveal atrophy, the formation of intraretinal pigment plaques, and subretinal neovascularization. 1 However, up until recently, OCT has been unable to provide information on the functional microvasculature in the central macula or about blood flow.…”

Genetic Disruption of Serine Biosynthesis is a Key Driver of Macular Telangiectasia Type 2 Etiology and Progression

“…The dashed line represents the nominal significance of p=0.05. The top right corner displays the ETDRS grid for the right eye (OD)29 used to divide the endophenotypes into 9 retinal areas; 1: foveal area, 2: superior inner area, 3: nasal inner area, 4: inferior inner area, 5: temporal inner area, 6: superior outer area, 7: nasal outer area, 8: inferior outer area, and 9: temporal outer area.Although definitions vary across the literature, for simplicity in this manuscript we define the pink area as the 'MacTel [onset] area' while the green areas are MacTel 'progression areas'.…”

Using Patient-Level Data to Develop Meaningful Cross-Trial Comparisons of Visual Impairment in Individuals with Diabetic Macular Edema

“…More recent studies (VIVID-DME/VISTA-DME) [ 13 ] used Cirrus OCT (Carl Zeiss Meditec), which is a spectral-domain OCT (SD-OCT) [ 19 ]. Because it has been shown that CRT values can be lower when measured with TD-OCT than with SD-OCT [ 20 , 21 ], the RESTORE baseline CRT measurements were converted into SD-CRT values using published data linking Stratus OCT and Cirrus OCT measurements [ 20 ]. Specifically, RESTORE baseline CRT was increased by a mean of 39 μm [standard deviation (SD): 25] [ 20 ].…”