Faculty Bibliography

OBJECTIVE: To investigate the capabilities of ultrahigh-resolution optical coherence tomography (UHR OCT); to compare with the commercially available OCT standard-resolution system, StratusOCT, for imaging of idiopathic juxtafoveal retinal telangiectasis (IJT); and to demonstrate that UHR OCT provides additional information on disease morphology, pathogenesis, and management. DESIGN: Retrospective, observational, interventional case series. PARTICIPANTS: Nineteen eyes of 10 patients diagnosed with IJT in at least one eye. METHOD: All patients were imaged with UHR OCT and StratusOCT at the same visit. A subset of patients was also imaged before and after treatment of IJT. MAIN OUTCOME MEASURES: Ultrahigh- and standard-resolution cross-sectional tomograms of IJT pathology. RESULTS: Using both standard- and ultrahigh-resolution OCT, we identified the following features of IJT: (1) a lack of correlation between retinal thickening on OCT and leakage on fluorescein angiography, (2) loss and disruption of the photoreceptor layer, (3) cystlike structures in the foveola and within internal retinal layers such as the inner nuclear or ganglion cell layers, (4) a unique internal limiting membrane draping across the foveola related to an underlying loss of tissue, (5) intraretinal neovascularization near the fovea, and (6) central intraretinal deposits and plaques. In 63% of cases, the presence of abnormal vessels and a discontinuity of the photoreceptor layer correlated with visual acuity. CONCLUSIONS: Ultrahigh-resolution OCT improves visualization of the retinal pathology associated with IJT and allows identification of new features associated with it. Some of these features, such as discontinuity of the photoreceptor layer, are revealed only by UHR OCT.

An upgraded optical coherence tomography system with integrated retinal tracker (TOCT) was developed. The upgraded system uses improved components to extend the tracking bandwidth, fully integrates the tracking hardware into the optical head of the clinical OCT system, and operates from a single software platform. The system was able to achieve transverse scan registration with sub-pixel accuracy (~10 microm). We demonstrate several advanced scan sequences with the TOCT, including composite scans averaged (co-added) from multiple B-scans taken consecutively and several hours apart, en face images collected by summing the A-scans of circular, line, and raster scans, and three-dimensional (3D) retinal maps of the fovea and optic disc. The new system achieves highly accurate OCT scan registration yielding composite images with significantly improved spatial resolution, increased signal-to-noise ratio, and reduced speckle while maintaining well-defined boundaries and sharp fine structure compared to single scans. Precise re-registration of multiple scans over separate imaging sessions demonstrates TOCT utility for longitudinal studies. En face images and 3D data cubes generated from these data reveal high fidelity image registration with tracking, despite scan durations of more than one minute.