scholarly journals Assessment of Detailed Photoreceptor Structure and Retinal Sensitivity in Diabetic Macular Ischemia Using Adaptive Optics-OCT and Microperimetry

2021 ◽  
Vol 62 (13) ◽  
pp. 1
Author(s):  
Felix Datlinger ◽  
Lorenz Wassermann ◽  
Adrian Reumueller ◽  
Dorottya Hajdu ◽  
Irene Steiner ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Retinal Sensitivity ◽  
Macular Ischemia

scholarly journals Retinal Sensitivity Loss Correlates with Deep Capillary Plexus Impairment in Diabetic Macular Ischemia

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Fabio Scarinci ◽  
Monica Varano ◽  
Mariacristina Parravano
Keyword(s):  
Optical Coherence Tomography ◽  
Optical Coherence Tomography Angiography ◽  
Diabetic Patients ◽  
Retinal Sensitivity ◽  
Optical Coherence ◽  
Type 2 Diabetic Patients ◽  
Sensitivity Loss ◽  
Capillary Plexus ◽  
Macular Ischemia ◽  
Sd Oct

Purpose. To assess retinal sensitivity and retinal morphologic changes of capillary nonperfused areas in diabetic macular ischemia. Methods. Observational cross-sectional study. Patients were examined at IRCCS—Bietti Foundation, Rome, Italy. Fourteen consecutive diabetic eyes showing outer retinal changes on spectral domain optical coherence tomography B-scan were included. Ten eyes of ten diabetic patients with normal outer retinal structure on SD-OCT were included as controls. All eyes underwent optical coherence tomography angiography (OCTA) and MP1 microperimetry. To explore the outer retina findings and localized areas of capillary nonperfusion at the superficial and deep capillary plexus, we used the Spectralis HRA + OCTA (Heidelberg Engineering, Heidelberg, Germany). The B-scans as either normal or having outer retinal disruption and the enface images at the level of the superficial and/or deep capillary plexus were evaluated to identify areas of capillary nonperfusion. Results. Fourteen eyes of 12 consecutive type 2 diabetic patients with outer retinal disruption on SD-OCT showed that areas of capillary nonperfusion of the deep capillary plexus were colocalized to areas of reduced retinal sensitivity. Conclusions. On optical coherence tomography angiography, areas of capillary nonperfusion of deep capillary plexus due to macular ischemia are associated with photoreceptor structural abnormalities and retinal sensitivity loss on microperimetry. This highlights that the health status of deep capillary plexus and not only the choroid is important to the oxygen requirements of the photoreceptors in patients with diabetic macular ischemia. Also, the anatomical and functional consequences of these findings might help to explore the efficacy of new therapy into the macular area in clinical practice.

scholarly journals Adaptive Optics Reveals Photoreceptor Abnormalities in Diabetic Macular Ischemia

PLoS ONE ◽  
2017 ◽  
Vol 12 (1) ◽  
pp. e0169926 ◽  
Author(s):  
Peter L. Nesper ◽  
Fabio Scarinci ◽  
Amani A. Fawzi
Keyword(s):  
Adaptive Optics ◽  
Macular Ischemia

scholarly journals Persistent Dark Cones in Oligocone Trichromacy Revealed by Multimodal Adaptive Optics Ophthalmoscopy

2021 ◽  
Vol 13 ◽  
Author(s):  
Joanne Li ◽  
Tao Liu ◽  
Oliver J. Flynn ◽  
Amy Turriff ◽  
Zhuolin Liu ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Visual Acuity ◽  
Color Vision ◽  
Adaptive Optics ◽  
Retinal Sensitivity ◽  
Photoreceptor Layer ◽  
Normal Visual Acuity ◽  
Normal Color Vision ◽  
Retinal Disorders ◽  
Cone Density

Dark cone photoreceptors, defined as those with diminished or absent reflectivity when observed with adaptive optics (AO) ophthalmoscopy, are increasingly reported in retinal disorders. However, their structural and functional impact remain unclear. Here, we report a 3-year longitudinal study on a patient with oligocone trichromacy (OT) who presented with persistent, widespread dark cones within and near the macula. Diminished electroretinogram (ERG) cone but normal ERG rod responses together with normal color vision confirmed the OT diagnosis. In addition, the patient had normal to near normal visual acuity and retinal sensitivity. Occasional dark gaps in the photoreceptor layer were observed on optical coherence tomography, in agreement with reflectance AO scanning light ophthalmoscopy, which revealed that over 50% of the cones in the fovea were dark, increasing to 74% at 10° eccentricity. In addition, the cone density was 78% lower than normal histologic value at the fovea, and 20–40% lower at eccentricities of 5–15°. Interestingly, color vision testing was near normal at locations where cones were predominantly dark. These findings illustrate how a retina with predominant dark cones that persist over at least 3 years can support near normal central retinal function. Furthermore, this study adds to the growing evidence that cones can continue to survive under non-ideal conditions.

scholarly journals Structural and Function Correlation of Cone Packing Utilizing Adaptive Optics and Microperimetry

2015 ◽  
Vol 2015 ◽  
pp. 1-4 ◽  
Author(s):  
Dabir Supriya ◽  
Mangalesh Shwetha ◽  
Kumar Kiran Anupama ◽  
Kurian Kummelil Mathew ◽  
Tos T. J. M. Berendschot ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Packing Density ◽  
Statistical Significance ◽  
Retinal Sensitivity ◽  
Cone Mosaic ◽  
Functional Aspects ◽  
Function Correlation ◽  
Correlation Tests ◽  
And Function ◽  
Age Range

Aim. To assess the functional aspects of cone mosaic and correlate cone packing with retinal sensitivity utilizing microperimetry in emmetropes at different eccentricities.Methods. Twenty-four healthy volunteers underwent microperimetry (MAIA Centervue, Italy) and assessment of photoreceptors using adaptive optics retinal camera, rtx1 (Imagine Eyes, Orsay, France), at 2 and 3 degrees from the foveal centre in 4 quadrants: superior, inferior, temporal, and nasal. Data was analyzed using SPSS version 17 (IBM). Spearman’s correlation tests were used to establish correlation between mean cone packing density and retinal sensitivity at different quadrants.Results. Thirteen females and 11 males (age range 20–40 years) were included. The cone density was found to be significantly different among all quadrants (temporal = 25786.68/mm2 ± 4367.07/mm2, superior = 23009.35/mm2 ± 5415.81/mm2, nasal = 22838.09/mm2 ± 4166.22/mm2, and inferior = 21097.53/mm2 ± 4235.84/mm2). A statistical significanceP<0.008was found between orthogonal meridians, that is, temporal, nasal48624.77/mm2>superior, inferior (44106.88/mm2). A drop in retinal sensitivity was observed as the eccentricity increasedP<0.05. It was also found that as cone packing density decreased retinal sensitivity also decreasedP<0.05in all quadrants. This was observed at both 2 and 3 degrees.Conclusion. It is of crucial importance to establish normative variations in cone structure-function correlation. This may help in detection of subtle pathology and its early intervention.

Adaptive optics (astronomy)

AccessScience ◽  
2015 ◽  
Keyword(s):  
Adaptive Optics

Preservation of retinal sensitivity in central visual field after panretinal photocoagulation in diabetics

1996 ◽  
Vol 10 (1) ◽  
pp. 48 ◽  
Author(s):  
Young H. Yoon ◽  
Joungkoo Lee ◽  
Yong J. Kim
Keyword(s):  
Visual Field ◽  
Panretinal Photocoagulation ◽  
Retinal Sensitivity ◽  
Central Visual Field

Adaptive optics with adaptive filtering and control

2004 ◽  
Author(s):  
Yu-Tai Liu ◽  
S. Gibson
Keyword(s):  
Adaptive Optics ◽  
Adaptive Filtering ◽  
And Control

Accounting for mirror dynamics in optimal Adaptive Optics control

2009 ◽  
Author(s):  
Carlos Correia ◽  
Henri-Francois Raynaud ◽  
Caroline Kulcsar ◽  
Jean-Marc Conan
Keyword(s):  
Adaptive Optics

The Condition for Absolute Stability of an Electroelastic Actuator Control System for Nanomechatronics

2020 ◽  
Vol 10 (10) ◽  
pp. 52-58
Author(s):  
Sergey M. AFONIN ◽  
Keyword(s):  
Control System ◽  
Adaptive Optics ◽  
Absolute Stability ◽  
Deformation Characteristic ◽  
Straight Line Segment ◽  
Control Mechanisms ◽  
Relative Width ◽  
Random Inputs ◽  
Deformation Control ◽  
Actuator Control

An electroelastic actuator for nanomechatronics is used in nanotechnology, adaptive optics, microsurgery, microelectronics, and biomedicine to actuate or control mechanisms, systems based on the electroelastic effect, and to convert electrical signals into mechanical displacements and forces. In nanomechatronic systems, a piezoactuator is used in scanning microscopy, laser systems, in astronomy for precision alignment, for compensation of temperature, gravitational deformations and atmospheric turbulence, focusing, and stabilizing the image. In this study, a condition for absolute stability of an electroelastic actuator control system for nanomechatronics under deterministic and random inputs is obtained. A number of equilibrium positions in an electroelastic actuator mechatronic control system are found, the totality of which is represented by a straight line segment. The electroelastic actuator’s deformation control system dead band relative width is determined for the actuator’s symmetric and asymmetric hysteresis characteristics. Under deterministic inputs and with fulfilling the condition for the derivative of the nonlinear hysteresis actuator deformation characteristic, the set of equilibrium positions of the electroelastic actuator control system for nanomechatronics is absolutely stable. Under random inputs, the system absolute stability with respect to the mathematical expectations of the electroelastic actuator mechatronic control system equilibrium positions has been determined subject to fulfilling the condition on the derivative of the actuator hysteresis characteristic.

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