Search

Purpose: To investigate the changes in retinal arterial architecture after treatment with voretigene neparvovec in patients with retinal dystrophy caused by bi‐allelic mutations in the RPE65 gene. Methods: Sixteen eyes treated with voretigene neparvovec at the University Eye Clinic in Tuebingen, Germany, underwent adaptive optics ophthalmoscopy (AO) imaging at baseline and 2 weeks, 1, 3, 6 and 12 months after treatment. Follow‐up was performed in six eyes of four patients. For each eye, five different positions at arterial vessels were selected and the wall‐to‐lumen ratio (WLR), the lumen diameter (LD) and the wall cross‐sectional area (WCSA) were measured by the manufacturer's software over the observational period. Results: Vast retinal atrophy dominated all gained AO images. WLR fluctuated in the observation period without statistically significant change. LD and WCSA changed significantly after 2 weeks from the baseline examination and returned to values similar to baseline thereafter. There were no signs of inflammation such as macrophages or perivascular accumulated fluid visible. Conclusion: AO imaging of the retinal vessels in RPE65‐associated retinal dystrophies (IRD) is challenging. There was no change in the retinal arterial vasculature over the observation period of 12 months that would indicate inflammatory changes. Decrease of the LD and WCSA shortly after treatment might be caused by the perioperative prednisolone intake. AO of retinal vessels can be used as a diagnostic module to complement monitoring the disease and effects of genetic treatments if the acquisition is possible in selected cases. [ABSTRACT FROM AUTHOR]

Purpose: To compare swept source OCTA device, with and without the extended field imaging (EFI) technique, to standard fluorescein angiography (FA) in the clinical practice. Methods: Consecutive patients with vascular disorder patients underwent FA with 55-degree lens (Spectralis Heidelberg Engineering, Heidelberg, Germany) and OCTA with the prototype PlexElite (Carl Zeiss Meditec, Dublin, CA) using a 12 mm x 12 mm volume scan pattern centered on the fovea and a prototype of + 20.00-diopter designed specifically by Zeiss. The imaging methods were compared for visible field of view, extension of non-perfused areas, presence and number of neovessels, vessel density (VD) and fractal dimension (FD). Results: Forty-three eyes of 27 patients were included. The mean extension ratio of EFI SS-OCTA compared to SS-OCTA without EFI and FA were 1.97 ± 0.02 and 0.85 ± 0.01. The mean extension of non-perfused areas with EFI SS-OCTA (34.22 ± 33.4 mm2) was significantly higher than SS-OCTA without EFI (20.46 ± 18.70 mm2), and with FA (27.55 ± 4.4 mm2). The mean VD and FD of EFI SS-OCTA were significantly different compared to SS-OCT without EFI. Conclusions: EFI SS-OCTA captured larger areas than SS-OCTA without EFI and FA. OCTA in a single shot is able to obtain more information of the retina without the use of montage techniques. Despite the determination of retinal ischemia seems to be easier and more accurate using EFI SS-OCTA, FA offers more details of the perfusion status of the retina. [ABSTRACT FROM AUTHOR]

Purpose: A suspicious optic nerve head (ONH) appearance, with abnormal cupping or increased cup‐to‐disc ratio, is associated to a strong risk factor for glaucoma. Typical devices to analyse the structure of the ONH are optical coherence tomography or scanning laser ophthalmoscopy. Those devices provide parameters to describe the status of an ONH like its depth, width or volume. We show that these parameters for glaucoma diagnosis can be obtained with a commercial fundus camera using an adapted light field (LF) camera providing a one‐shot 3d retinal image. Methods: We examined a human eye (32 years, male) 5 times during one session in compliance with the Declaration of Helsinki. The images were taken with a fundus camera (FF450, Carl Zeiss Meditec AG, Germany) combined with an industrial LF camera (RX12, Raytrix GmbH, Germany). The generic depth estimation was performed with the Raytrix LF software (RxLive 5.0.031.0) using the Depth Raycast Light algorithm. The results were exported as 3d point lists in ascii XYZ format and for further processing imported in Matlab (R2018b, MathWorks, U.S.). The imported data were pre‐processed, the papilla midpoints automatically detected and the optic nerve head was horizontally sliced in 0.01 virtual depth steps starting from the base upwards until the papilla rim was reached. We compared the overall virtual depth, the virtual volume and the virtual area per virtual depth step, each as relative difference. Results: All LF images showed visually a very good image quality. The depth estimations were successful and covered the complete image areas. The overall virtual depth range was 95.9% to 101.4% with mean of 100% (±2.36%). The overall virtual volume range was 97.5% to 102.2% with mean of 100% (±2.1%). The area per virtual depth range was 2.5% to 174.5% with mean of 100% (±10.9%) whereas the larger deviations appeared in the lowermost slices. Conclusions: Fundus cameras with LF technique are able to provide one‐shot 3d retinal images. This light field images allow the evaluation of typical parameters for glaucoma diagnosis and show a very good reproducibility. [ABSTRACT FROM AUTHOR]

Purpose: One strong risk factor for glaucoma is a suspicious optic nerve head appearance and an increase in depth. With the upcoming light‐field (LF) technology one‐shot 3D retinal imaging and measuring is possible. Due to optical aberrations such as astigmatism, the imaged depth can be distorted. The study presented here investigated the influence of astigmatism on LF image quality and depth estimation using an eye model. Methods: We developed a new eye model that added astigmatism by integrating an additional cylindrical lens between the cornea and lens. We used cylindrical lenses from −4 to 0 dpt in 1 dpt steps in vertical and horizontal orientations. The fundus was modelled as a half hollow sphere with a radius of 10 mm and a central papilla with 0.8 mm depth. The fundus was coated with red acrylic lacquer, and vessels were drawn with a thin brush with black acrylic lacquer. LF fundus images (15 for each cylindrical lens and orientation) were taken with a fundus camera (FF450, Carl Zeiss Meditec AG, Germany) equipped with an industrial LF camera (RX12, Raytrix GmbH, Germany). Depth measurements were performed with the Raytrix LF software (RxLive 5.0.046.0) as difference from a vertical vessel to a horizontal orientated vessel. The same measuring point was used for all images. Results: The LF images taken with a cylindrical lens show a visually poorer image quality. Depth estimates were only possible in the central image area. The fundus images show increasing depth differences between vertical and horizontal vessels with increasing astigmatism up to 0.37 mm at −4 dpt in contrast to the flat imaged fundus without cylindrical lens. The sign of the depth differences changes when the orientation of the inserted cylindrical lens is changed. Conclusions: The imaged LF of a fundus of an astigmatic eye model is measurably distorted and affects vertical and horizontal structures differently. This must be taken into account when evaluating and interpreting LF depth measurements. [ABSTRACT FROM AUTHOR]

Purpose Two different systems, adaptive optics scanning laser ophthalmoscope (AOSLO), and Spectral Domain Ophtalmoloscopy (SD‐OCT) were used to visualize cones in the outer neurosensory retina overlying soft macular drusen and the surrounding retinal areas. Methods High resolution images were obtained with Adaptive Optics (AO) in addition to complete ophthalmic examination including BCVA on ETDRS chart, biomicroscopic examination, autofluorescence imaging, fluorescein and indocyanine angiographies (HRA2 Heidelberg ,Germany) and SD‐OCT. The AO image are then compared with conventional infrared and SD‐OCT. Soft macular drusen from 50 patients (age between 65 and 85) visible on the scanning laser ophthalmoscope(SLO) examination were evaluated included in the study Results The soft drusen were visible in AO images as generally round areas delimited by a peripheral low‐reflectance line. The highly reflective photoreceptor inner/outer segment junction (IS/OS) can be used as a pattern of photoreceptors integrity in SD‐OCT images. In areas where the IS/OS junction is absent on SD‐OCT, no cones are visualized in registered AOSLO images. In the inner area of many drusen, hyper reflective spots of a size between 2 and 15 µm were sometimes isolated, sometimes grouped into tight aggregates of 2 to 40 components. Cone photoreceptors were visible in areas between drusen in most AO images, however the mosaic image sharpness was significantly less uniform in these elderly patients than previously observed in younger, healthy retinas. Conclusion This study shows the synergistic nature of these two high‐resolution retinal imaging systems The microscopic characteristics of soft drusen on AO imaging suggest some analogy with the anatomopathologic characteristics. AO technology will be a powerful tool to refine their clinical classification [ABSTRACT FROM AUTHOR]