Rayfoss3334
The development of new approaches to human vision restoration could be greatly accelerated with the use of nonhuman primate models; however, there is a paucity of primate models of outer retina degeneration with good spatial localization. To limit ablation to the photoreceptors, we developed a new approach that uses a near-infrared ultrafast laser, focused using adaptive optics, to concentrate light in a small focal volume within the retina.
In the eyes of eight anesthetized macaques, 187 locations were exposed to laser powers from 50 to 210 mW. Laser exposure locations were monitored for up to 18 months using fluorescein angiography (FA), optical coherence tomography (OCT), scanning laser ophthalmoscopy (SLO), adaptive optics scanning laser ophthalmoscope (AOSLO) reflectance imaging, two-photon excited fluorescence (TPEF) ophthalmoscopy, histology, and calcium responses of retinal ganglion cells.
This method produced localized photoreceptor loss with minimal axial spread of damage to other retinal layers, verified by
structural imaging and histologic examination, although in some cases evidence of altered autofluorescence was found in the adjacent retinal pigment epithelium (RPE). Functional assessment using blood flow imaging of the retinal plexus and calcium imaging of the response of ganglion cells above the photoreceptor loss shows that inner retinal circuitry was preserved.
Although different from a genetic model of retinal degeneration, this model of localized photoreceptor loss may provide a useful testbed for vision restoration studies in nonhuman primates.
With this model, a variety of vision restoration methods can be tested in the non-human primate.
With this model, a variety of vision restoration methods can be tested in the non-human primate.
To determine if immunological markers (1) are significantly different between autoimmune retinopathy (AIR) patients and controls and (2) correlate with disease progression in AIR patients.
We enrolled patients with a possible AIR diagnosis, as well as control participants without eye disease, autoimmunity, or cancer. Immunological markers were tested in all participants. In addition, AIR patients had up to three blood draws for testing over their disease course. For AIR patients, clinical measures, including visual acuity (VA) and Goldmann visual field (GVF) area, were recorded at each draw. We used the Mann-Whitney
test to compare the immunological markers between AIR patients and controls. We used multilevel mixed-effect regression to investigate the correlation between markers and clinical parameters over time in AIR patients.
Seventeen patients with AIR and 14 controls were included. check details AIR patients had a higher percent of monocytes (
= 3.076,
= 0.002). An increase in immunoglobulin G against recoverin was correlated with a VA decrease (β = 0.0044,
< 0.0001). An increase in monocyte proportion was correlated with a decrease in GVF area (β = -7.27,
= 0.0021). Several markers of B-cell depletion were correlated with GVF improvement.
Monocytes may play a role in AIR pathophysiology and be a disease activity marker. B-cell depletion markers correlated with clinical parameter improvement, particularly GVF.
This work elucidates immunologic markers that may improve the accuracy of diagnosis and treatment of AIR.
This work elucidates immunologic markers that may improve the accuracy of diagnosis and treatment of AIR.
Evaluating mobility aids in naturalistic conditions across many days is challenging owing to the sheer amount of data and hard-to-control environments. For a wearable video camera-based collision warning device, we present the methodology for acquisition, reduction, review, and coding of video data for quantitative analyses of mobility outcomes in blind and visually impaired participants.
Scene videos along with collision detection information were obtained from a chest-mounted collision warning device during daily use of the device. The recorded data were analyzed after use. Collision risk events flagged by the device were manually reviewed and coded using a detailed annotation protocol by two independent masked reviewers. Data reduction was achieved by predicting agreements between reviewers based on a machine learning algorithm. Thus, only those events for which disagreements were predicted would be reviewed by the second reviewer. Finally, the ultimate disagreements were resolved via consensus, and mobility-related outcome measures such as percentage of body contacts were obtained.
There were 38 hours of device use from 10 participants that were reviewed by both reviewers, with an agreement level of 0.66 for body contacts. The machine learning algorithm trained on 2714 events correctly predicted 90.5% of disagreements. For another 1943 events, the trained model successfully predicted 82% of disagreements, resulting in 81% data reduction.
The feasibility of mobility aid evaluation based on a large volume of naturalistic data is demonstrated. Machine learning-based disagreement prediction can lead to data reduction.
These methods provide a template for determining the real-world benefit of a mobility aid.
These methods provide a template for determining the real-world benefit of a mobility aid.
To evaluate the changes of retinal capillary nonperfusion areas and retinal capillary vessel density of the superficial capillary plexus (SCP) and deep capillary plexus in patients with diabetes with diabetic macular edema treated with an intravitreal dexamethasone implant (IDI).
We enrolled 28 patients with diabetic retinopathy and diabetic macular edema candidates to IDI. All patients underwent widefield optical coherence tomography angiography with PLEX Elite 9000 device with 15 × 9 mm scans centered on the foveal center at baseline, 1 month, 2 months, and 4 months after IDI. In all the patients, the variation of the retinal capillary nonperfusion areas and of the retinal vessel density of the SCP and deep capillary plexus were calculated using an automatic software written in Matlab (MathWorks, Natick, MA).
During follow-up, SCP showed a statistically significant reduction of ischemic areas at 1 month after IDI (
= 0.04) and slightly increased not significantly thereafter (
= 0.15). The percentage of nonperfusion areas changed from 11.