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Hyperreflective dots are a common but highly variable feature of optical coherence tomography (OCT) scans of the retina. We studied the spatial characteristics and perfusion of hyperreflective dots using both structural and angiographic OCT B-scans of the macula in 16 eyes in 8 healthy subjects and 8 patients with diabetic retinopathy without macular edema. Hyperreflective dots were manually graded in a 1000 µm parafoveal area by number, diameter, location and perfusion status and traced through adjacent B-scans at 11 µm intervals to determine their length. Thereby, this study defined a procedure to identify granular and elongated hyperreflective elements and differentiate between presumably perfused and occluded capillaries. The latter were only found in the diabetic patients. This classification can potentially be automated to non-invasively identify capillary non-perfusion in vivo.

Purpose To describe the finding of bright hyperautofluorescent streaks in the peripheral retina in tuberous sclerosis. Observations A woman with a pathogenic TSC1 mutation and cutaneous manifestations of tuberous sclerosis underwent fundus examination and was found to have a cluster of thin, yellowish streaks in the inferior peripheral fundus of her left eye. The streaks were hyperautofluorescent in blue light and associated with irregular thickening of the photoreceptor-pigment epithelium complex on optical coherence tomography. Conclusions and importance The cluster of outer retinal abnormalities in a sector of the peripheral retina in one eye of a TSC1 patient has features in common with the more centrally located and less numerous lesions called achromatic patches. The resemblance of the streak pattern with the pattern of hypoautofluorescence in X-linked retinopathies suggests that the streaks may represent a clone of cells derived from a single somatic mutation in TSC1. The identification of this lesion type expands the scope of conditions that can be diagnosed by fundus imaging.

A compact multi-modal and multi-scale retinal imaging instrument is developed for clinical use. High resolution retinal images visualizing photoreceptors, choriocapillaris, and different vasculatures can be obtained by utilizing this instrument.

Purpose:To describe a unilateral foveal vitelliform lesion associated with subnormal visual acuity in a choroideremia carrier.Methods:A retrospective case report, assessment of the best-corrected visual acuity, fundus photography, wide-angle scanning laser ophthalmoscopy, optical coherence tomography, and microperimetry.Results:A 37-year-old woman with a pathogenic 907C>T mutation in the choroideremia gene encoding Rab escort protein-1 presented with blurred vision in her left eye.The Snellen best-corrected visual acuity was 20/20 in the right eye and 20/32 in the left eye, a unilateral decrease because it was 20/20 in both eyes at the most recent examination nine years earlier. In the left eye, a large vitelliform lesion with a diameter of 1,300 µm had developed in the fovea, whereas in the right eye, a smaller similar lesion was seen close to the fovea. Both eyes showed classical radial patterns of multiple bright fundus patches with associated autofluorescence defects and focal drusenoid lesions of the outer retina.Conclusion:With its large size and foveal location the vitelliform lesion in this patient's left eye is an unusual manifestation in an otherwise common Rab escort protein-1 mutation carrier state, and its unilaterality fits the assumption of random X-chromosome inactivation.

Purpose To describe the migration of an outer retinal element using longitudinal multimodal imaging. Observations In the retina of a healthy 7-year-old girl, movement of a hyperreflective element of 15 μm extent was seen using optical coherence tomography (OCT), confocal scanning laser ophthalmoscopy (cSLO), and adaptive optics fundus photography (AO). On the OCT B-scan, the element initially appeared at the level of the outer limiting membrane with an umbra reaching the retinal pigment epithelium from where it gradually diminished and disappeared over 33 days. A corresponding disruption of the photoreceptor pattern on AO diminished over 52 days. Conclusions and importance This non-invasive observation of an isolated, cell-sized, migrating element in the human retina was made in vivo in the absence of confounding retinal disease or similar nearby elements. Based on prior preclinical observations we hypothesize that such a migrating element could be a macrophage. The case provides information about the time-scale and resolution needed for the monitoring of infiltrative processes in the retina.

Optical coherence tomography (OCT) is a useful technique to monitor retinal damage. We present an automatic method to accurately classify rodent OCT images in healthy and pathological (before and after 14 days of intravitreal injection of Endothelin-1, respectively) making use of the DenseNet-201 architecture fine-tuned and a customized top-model. We validated the performance of the method on 1912 OCT images yielding promising results ( AUC=0.99±0.01 in a P=15 leave-P-out cross-validation). Besides, we also compared the results of the fine-tuned network with those achieved training the network from scratch, obtaining some interesting insights. The presented method poses a step forward in understanding pathological rodent OCT retinal images, as at the moment there is no known discriminating characteristic which allows classifying this type of images accurately. The result of this work is a very accurate and robust automatic method to distinguish between healthy and a rodent model of glaucoma, which is the backbone of future works dealing with human OCT images., Animal experiment permission was granted by the Danish Animal Experimentation Council (license number: 2017-15-0201-01213). We gratefully acknowledge the support of NVIDIA Corporation with the donation of the Titan Xp GPU used for this research. This work was supported by the Project GALAHAD [H2020-ICT-2016-2017, 732613]