Evaluation of effects the ocular metrics (eye movements and ocular aberrations) have on image quality of in vivo retinal optical coherence tomography angiography (OCTA)

2021 ◽  
Author(s):  
Kari V. Vienola ◽  
Denise Valente ◽  
John S. Werner ◽  
Ravi S. Jonnal ◽  
Robert J. Zawadzki
Keyword(s):  
Optical Coherence Tomography ◽  
Eye Movements ◽  
Image Quality ◽  
Optical Coherence Tomography Angiography ◽  
Optical Coherence ◽  
Ocular Aberrations

scholarly journals Effect of night work on image quality of optical coherence tomography angiography

2019 ◽  
Vol 31 (4) ◽  
pp. 438-441
Author(s):  
Mojtaba Abrishami ◽  
Pouran Fadakar ◽  
Masoud Mirghorbani ◽  
Ahmad Masoumi ◽  
Samira Hassanzadeh
Keyword(s):  
Optical Coherence Tomography ◽  
Image Quality ◽  
Optical Coherence Tomography Angiography ◽  
Night Work ◽  
Optical Coherence

scholarly journals Evaluating Retinal and Choroidal Perfusion Changes after Isometric and Dynamic Activity Using Optical Coherence Tomography Angiography

Diagnostics ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 808
Author(s):  
Max Philipp Brinkmann ◽  
Nikolas Xavier Kibele ◽  
Michelle Prasuhn ◽  
Vinodh Kakkassery ◽  
Mario Damiano Toro ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Optical Coherence Tomography Angiography ◽  
Isometric Exercise ◽  
Dynamic Exercise ◽  
Exercise Heart Rate ◽  
Optical Coherence ◽  
Dynamic Activity ◽  
Capillary Plexus ◽  
Choroidal Perfusion

Optical coherence tomography angiography (OCTA) is a non-invasive tool for imaging and quantifying the retinal and choroidal perfusion state in vivo. This study aimed to evaluate the acute effects of isometric and dynamic exercise on retinal and choroidal sublayer perfusion using OCTA. A pilot study was conducted on young, healthy participants, each of whom performed a specific isometric exercise on the first day and a dynamic exercise the day after. At baseline and immediately after the exercise, heart rate (HR), mean arterial pressure (MAP), superficial capillary plexus perfusion (SCPP), deep capillary plexus perfusion (DCPP), choriocapillaris perfusion (CCP), Sattlers’s layer perfusion (SLP), and Haller’s layer perfusion (HLP) were recorded. A total of 34 eyes of 34 subjects with a mean age of 32.35 ± 7.87 years were included. HR as well as MAP increased significantly after both types of exercise. Both SCPP and DCPP did not show any significant alteration due to isometric or dynamic exercise. After performing dynamic exercise, CCP, SLP, as well as HLP significantly increased. Changes in MAP correlated significantly with changes in HLP after the dynamic activity. OCTA-based analysis in healthy adults following physical activity demonstrated a constant retinal perfusion, supporting the theory of autoregulatory mechanisms. Dynamic exercise, as opposed to isometric activity, significantly changed choroidal perfusion. OCTA imaging may represent a novel and sensitive tool to expand the diagnostic spectrum in the field of sports medicine.

scholarly journals Swept Source Optical Coherence Tomography Angiography for Contact Lens-Related Corneal Vascularization

2016 ◽  
Vol 2016 ◽  
pp. 1-3 ◽  
Author(s):  
Marcus Ang ◽  
Yijun Cai ◽  
Anna C. S. Tan
Keyword(s):  
Optical Coherence Tomography ◽  
Image Quality ◽  
Contact Lens ◽  
Optical Coherence Tomography Angiography ◽  
Quality Score ◽  
Image Quality Score ◽  
Optical Coherence ◽  
Swept Source ◽  
Corneal Vascularization ◽  
Significant Difference

Purpose. To describe a novel technique of adapting a swept-source optical coherence tomography angiography (OCTA) to image corneal vascularization.Methods. In this pilot cross-sectional study, we obtained 3 × 3 mm scans, where 100,000 A-scans are acquired per second with optical axial resolution of 8 μm and lateral resolution of 20 μm. This was performed with manual “XYZ” focus without the anterior segment lens, until the focus of the corneoscleral surface was clearly seen and the vessels of interest were in focus on the corresponding red-free image. En face scans were evaluated based on image quality score and repeatability.Results. We analyzed scans from 10 eyes (10 patients) with corneal vascularization secondary to contact lens use in 4 quadrants, with substantial repeatability of scans in all quadrants (mean image quality score 2.7 ± 0.7;κ=0.75). There was no significant difference in image quality scores comparing quadrants (superior temporal: 2.9 ± 0.6, superior nasal: 2.8 ± 0.4, inferior temporal: 2.5 ± 0.9, and inferior nasal: 2.4 ± 1.0;P=0.276) and able to differentiate deep and superficial corneal vascularization.Conclusion. This early clinical study suggests that the swept-source OCTA used may be useful for examining corneal vascularization, which may have potential for clinical applications such as detecting early limbal stem cell damage.

scholarly journals A practical guide to optical coherence tomography angiography interpretation

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Eugenia Custo Greig ◽  
Jay S. Duker ◽  
Nadia K. Waheed
Keyword(s):  
Optical Coherence Tomography ◽  
Optical Coherence Tomography Angiography ◽  
Image Interpretation ◽  
Age Related Macular Degeneration ◽  
Optical Coherence ◽  
Clinical Practices ◽  
Imaging Device ◽  
Age Related ◽  
Retinal Microvasculature

Abstract Background Optical coherence tomography angiography (OCTA) can image the retinal vasculature in vivo, without the need for contrast dye. This technology has been commercially available since 2014, however, much of its use has been limited to the research setting. Over time, more clinical practices have adopted OCTA imaging. While countless publications detail OCTA’s use for the study of retinal microvasculature, few studies outline OCTA’s clinical utility. Body This review provides an overview of OCTA imaging and details tips for successful interpretation. The review begins with a summary of OCTA technology and artifacts that arise from image acquisition. New methods and best practices to prevent image artifacts are discussed. OCTA has the unique ability among retinovascular imaging modalities to individually visualize each retinal plexus. Slabs offered in standard OCTA devices are reviewed, and clinical uses for each slab are outlined. Lastly, the use of OCTA for the clinical interpretation of retinal pathology, such as diabetic retinopathy and age-related macular degeneration, is discussed. Conclusion OCTA is evolving from a scientific tool to a clinical imaging device. This review provides a toolkit for successful image interpretation in a clinical setting.

Adaptive optics - optical coherence tomography for in vivo retinal imaging: effects of spectral bandwidth on image quality

2006 ◽  
Author(s):  
Robert J. Zawadzki ◽  
Steven M. Jones ◽  
Mingtao Zhao ◽  
Stacey S. Choi ◽  
Sophie S. Laut ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Image Quality ◽  
Adaptive Optics ◽  
Retinal Imaging ◽  
Optical Coherence ◽  
Spectral Bandwidth

scholarly journals Optical coherence tomography angiography image quality assessment at varying retinal expertise levels

2019 ◽  
Vol 31 (2) ◽  
pp. 161-167 ◽  
Author(s):  
Anne K. Woetzel ◽  
Jost L. Lauermann ◽  
Kiana Kreitz ◽  
Maged Alnawaiseh ◽  
Christoph R. Clemens ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Image Quality ◽  
Quality Assessment ◽  
Optical Coherence Tomography Angiography ◽  
Image Quality Assessment ◽  
Optical Coherence

scholarly journals Quantitative assessment of choriocapillaris flow deficits in diabetic retinopathy: A swept-source optical coherence tomography angiography study

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243830
Author(s):  
Yining Dai ◽  
Hao Zhou ◽  
Qinqin Zhang ◽  
Zhongdi Chu ◽  
Lisa C. Olmos de Koo ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Diabetic Retinopathy ◽  
Healthy Subjects ◽  
Optical Coherence Tomography Angiography ◽  
Optical Coherence ◽  
Swept Source ◽  
Significant Difference ◽  
En Face ◽  
The Mean

Purpose To quantitatively assess choriocapillaris (CC) flow deficits in eyes with diabetic retinopathy (DR) using swept-source optical coherence tomography angiography (SS-OCTA). Methods Diabetic subjects with different stages of DR and age-matched healthy subjects were recruited and imaged with SS-OCTA. The en face CC blood flow images were generated using previously published and validated algorithms. The percentage of CC flow deficits (FD%) and the mean CC flow deficit size were calculated in a 5-mm-diameter circle centered on the fovea from the 6×6-mm scans. Results Forty-five diabetic subjects and 27 control subjects were included in the study. The CC FD% in diabetic eyes was on average 1.4-fold greater than in control eyes (12.34±4.14% vs 8.82±2.61%, P < 0.001). The mean CC FD size in diabetic eyes was on average 1.4-fold larger than in control eyes (2151.3± 650.8μm2 vs 1574.4±255.0 μm2, P < 0.001). No significant difference in CC FD% or mean CC FD size was observed between eyes with nonproliferative DR and eyes with proliferative DR (P = 1.000 and P = 1.000, respectively). Conclusions CC perfusion in DR can be objectively and quantitatively assessed with FD% and FD size. In the macular region, both CC FD% and CC FD size are increased in eyes with DR. SS-OCTA provides new insights for the investigations of CC perfusion status in diabetes in vivo.

scholarly journals Optical Coherence Tomography Angiography of Early Stage 1a Retinal Hemangioblastoma in Von-Hippel-Lindau

2021 ◽  
Vol 8 (3) ◽  
pp. 15-18
Author(s):  
Ananya Goswami ◽  
Abhidnya Surve ◽  
Pradeep Venkatesh
Keyword(s):  
Optical Coherence Tomography ◽  
Optical Coherence Tomography Angiography ◽  
Early Stage ◽  
Optical Coherence ◽  
Von Hippel Lindau ◽  
Retinal Capillary ◽  
Capillary Plexus ◽  
Retinal Hemangioblastoma ◽  
Retinal Capillaries

Von-Hippel-Lindau (VHL) syndrome is characterized by focal vasoproliferative tumors of retinal capillaries called retinal capillary hemangio-blastomas (RCH). These tumors are initially small and can be easily missed if not looked for carefully. As they grow, these tumors are more demanding to treat and hence the importance of detecting them early and treating them. Herein, we describe and review the optical coherence tomography angiography (OCTA) of the early-stage lesion, which suggested the involvement of superficial and a deeper retinal capillary plexus. In addition, to helping us detect these lesions earlier, OCTA may also help to understand the in vivo changes occurring at an earlier phase.

scholarly journals Design and Optimization of a Linear Wavenumber Spectrometer with Cylindrical Optics for Line Scanning Optical Coherence Tomography

Sensors ◽  
2021 ◽  
Vol 21 (19) ◽  
pp. 6463
Author(s):  
Sevin Samadi ◽  
Javad Dargahi ◽  
Sivakumar Narayanswamy
Keyword(s):  
Optical Coherence Tomography ◽  
Image Quality ◽  
High Speed ◽  
High Efficiency ◽  
Optical Design ◽  
Optical Coherence ◽  
High Speed Imaging ◽  
Nonlinearity Error ◽  
Line Scanning

We report the design of a high-efficiency spectral-domain spectrometer with cylindrical optics for line scanning optical coherence tomography (OCT). The spectral nonlinearity in k space (wavenumber) lowers the depth-dependent signal sensitivity of the spectrometers. For linearizing, in this design, grating and prism have been introduced. For line scanning, a cylindrical mirror is utilized in the scanning part. Line scanning improves the speed of imaging compared to fly-spot scanning. Line scanning OCT requires a spectrometer that utilizes cylindrical optics. In this work, an optical design of a linear wavenumber spectrometer with cylindrical optics is introduced. While there are many works using grating and prism to linearize the K space spectrometer design, there is no work on linearizing the k-space spectrometer with cylindrical optics for line scanning that provides high sensitivity and high-speed imaging without the need for resampling. The design of the spectrometer was achieved through MATLAB and ZEMAX simulations. The spectrometer design is optimized for the broadband light source with a center wavelength of 830 ± 100 nm (8.607 μm−1− 6.756 μm−1 in k-space). The variation in the output angle with respect to the wavenumber can be mentioned as a nonlinearity error. From our design results, it is observed that the nonlinearity error reduced from 147.0115 to 0.0149 Δθ*μm within the wavenumber range considered. The use of the proposed reflective optics for focusing reduces the chromatic aberration and increases image quality (measured by the Strehl ratio (SR)). The complete system will provide clinicians a powerful tool for real-time diagnosis, treatment, and guidance in surgery with high image quality for in-vivo applications.

Sign in / Sign up

Export Citation Format

Share Document