scholarly journals Utilization potential of intraluminal optical coherence tomography for the Eustachian tube

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hayoung Byun ◽  
Yeon Hoon Kim ◽  
Jingchao Xing ◽  
Su-Jin Shin ◽  
Seung Hwan Lee ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Eustachian Tube ◽  
Balloon Dilatation ◽  
Optical Coherence ◽  
Cross Sectional ◽  
Anatomical Structures ◽  
Complex Anatomy ◽  
Before And After ◽  
Tubal Lumen ◽  
Oct Image

AbstractImaging the Eustachian tube is challenging because of its complex anatomy and limited accessibility. This study fabricated a fiber-based optical coherence tomography (OCT) catheter and investigated its potential for assessing the Eustachian tube anatomy. A customized OCT system and an imaging catheter, termed the Eustachian OCT, were developed for visualizing the Eustachian tube. Three male swine cadaver heads were used to study OCT image acquisition and for subsequent histologic correlation. The imaging catheter was introduced through the nasopharyngeal opening and reached toward the middle ear. The OCT images were acquired from the superior to the nasopharyngeal opening before and after Eustachian tube balloon dilatation. The histological anatomy of the Eustachian tube was compared with corresponding OCT images, The new, Eustachian OCT catheter was successfully inserted in the tubal lumen without damage. Cross-sectional images of the tube were successfully obtained, and the margins of the anatomical structures including cartilage, mucosa lining, and fat could be successfully delineated. After balloon dilatation, the expansion of the cross-sectional area could be identified from the OCT images. Using the OCT technique to assess the Eustachian tube anatomy was shown to be feasible, and the fabricated OCT image catheter was determined to be suitable for Eustachian tube assessment.

scholarly journals Comparison of swept-source versus spectral-domain optical coherence tomography angiography for detection of macular neovascularization

2021 ◽  
Author(s):  
Anna Lentzsch ◽  
Laura Schöllhorn ◽  
Christel Schnorr ◽  
Robert Siggel ◽  
Sandra Liakopoulos
Keyword(s):  
Optical Coherence Tomography ◽  
Optical Coherence Tomography Angiography ◽  
Spectral Domain ◽  
Optical Coherence ◽  
Cross Sectional ◽  
Swept Source ◽  
En Face ◽  
Increased Sensitivity ◽  
Sensitivity Specificity ◽  
Subretinal Hyperreflective Material

Abstract Purpose To compare swept-source (SS) versus spectral-domain (SD) optical coherence tomography angiography (OCTA) for the detection of macular neovascularization (MNV). Methods In this prospective cohort study, 72 eyes of 54 patients with subretinal hyperreflective material (SHRM) and/or pigment epithelial detachment (PED) on OCT possibly corresponding to MNV in at least one eye were included. OCTA scans were acquired using two devices, the PLEX Elite 9000 SS-OCTA and the Spectralis SD-OCTA. Fluorescein angiography (FA) was used as reference. Two graders independently evaluated en face OCTA images using a preset slab as well as a manually modified slab, followed by a combination of en face and cross-sectional OCTA. Results Sensitivity (specificity) for the automated slabs was 51.7% (93.0%) for SS-OCTA versus 58.6% (95.3%) for SD-OCTA. Manual modification of segmentation increased sensitivity to 79.3% for SS-OCTA but not for SD-OCTA (58.6%). The combination of en face OCTA with cross-sectional OCTA reached highest sensitivity values (SS-OCTA: 82.8%, SD-OCTA: 86.2%), and lowest number of cases with discrepancies between SS-OCTA and SD-OCTA (4.2%). Fleiss kappa as measure of concordance between FA, SS-OCTA, and SD-OCTA was 0.56 for the automated slabs, 0.60 for the manual slabs, and 0.73 (good agreement) for the combination of en face OCTA with cross-sectional OCTA. Concordance to FA was moderate for the automated slabs and good for manual slabs and combination with cross-sectional OCTA of both devices. Conclusion Both devices reached comparable results regarding the detection of MNV on OCTA. Sensitivity for MNV detection and agreement between devices was best when evaluating a combination of en face and cross-sectional OCTA.

scholarly journals Coherence tomography with broad bandwidth extreme ultraviolet and soft X-ray radiation

2021 ◽  
Vol 127 (4) ◽  
Author(s):  
S. Skruszewicz ◽  
S. Fuchs ◽  
J. J. Abel ◽  
J. Nathanael ◽  
J. Reinhard ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Near Infrared ◽  
Extreme Ultraviolet ◽  
Infrared Light ◽  
Imaging Method ◽  
Optical Coherence ◽  
Axial Resolution ◽  
Cross Sectional ◽  
X Ray ◽  
Broad Bandwidth

AbstractWe present an overview of recent results on optical coherence tomography with the use of extreme ultraviolet and soft X-ray radiation (XCT). XCT is a cross-sectional imaging method that has emerged as a derivative of optical coherence tomography (OCT). In contrast to OCT, which typically uses near-infrared light, XCT utilizes broad bandwidth extreme ultraviolet (XUV) and soft X-ray (SXR) radiation (Fuchs et al in Sci Rep 6:20658, 2016). As in OCT, XCT’s axial resolution only scales with the coherence length of the light source. Thus, an axial resolution down to the nanometer range can be achieved. This is an improvement of up to three orders of magnitude in comparison to OCT. XCT measures the reflected spectrum in a common-path interferometric setup to retrieve the axial structure of nanometer-sized samples. The technique has been demonstrated with broad bandwidth XUV/SXR radiation from synchrotron facilities and recently with compact laboratory-based laser-driven sources. Axial resolutions down to 2.2 nm have been achieved experimentally. XCT has potential applications in three-dimensional imaging of silicon-based semiconductors, lithography masks, and layered structures like XUV mirrors and solar cells.

scholarly journals Patterns of Macular Edema in Uveitis as Diagnosed by Optical Coherence Tomography in Tertiary Eye Center

2018 ◽  
Vol 10 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Sharad Gupta ◽  
Dev Narayan Shah ◽  
Sagun Narayan Joshi ◽  
Manoj Aryal ◽  
Lila Raj Puri
Keyword(s):  
Optical Coherence Tomography ◽  
Macular Edema ◽  
Serous Retinal Detachment ◽  
Posterior Uveitis ◽  
Invasive Technique ◽  
Optical Coherence ◽  
Fundus Fluorescein Angiography ◽  
Cross Sectional ◽  
Female Ratio ◽  
Uveitic Macular Edema

Aim: The aim of the study is to classify the patterns of uveitic macular edema using Optical Coherence Tomography as a diagnostic tool.Methodology: It is the Descriptive, cross-sectional study. All patients fulfilling the diagnostic criteria with Optical coherence tomography diagnosed macular edema were enrolled from 1 January 2012 to 30 June 2013. Patterns of uveitic macular edema were classified.Results: A total of 65 eyes of 47 patients were included. Twenty eight (59.57%) were male. The male to female ratio was 1.5:1. The mean age was 38 years (SD 14.68). Twenty nine patients (61.71%) had unilateral involvement and 18 (38.29%) had bilateral involvement. Forty five eyes of 33 cases (69.23%, 70.21%) had intermediate uveitis, followed by 10 eyes of 7 cases (15.38, 14.9%) of posterior uveitis, 6 eyes of 5 cases (9.23%, 10.63 %) of anterior uveitis and 4 eyes of 2 cases (6.16%,4.2%) of pan-uveitis. Patterns of macular edema were classified: diff use macular edema (DME), cystoid macular edema (CME) and serous retinal detachment (SRD) of which 35 (53.84%) eyes had CME. The etiological diagnosis was found in 7(14.90 %) out of 47 patients.Conclusion: A significant percentage of cases were idiopathic. Macular edema may go unnoticed unless OCT is performed. Macular detachment is an important feature of macular edema that affects visual acuity and is not readily detected by Fundus Fluorescein Angiography (FFA). Optical coherence tomography (OCT) is safe and non-invasive technique and has the potential for measuring changes in retinal thickness and axial extent of edema.

Ex Vivo assessment of competent strut coverage after coronary stenting by optical coherence tomography

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
R Bhoite ◽  
H Jinnouchi ◽  
F Otsuka ◽  
Y Sato ◽  
A Sakamoto ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Predictive Value ◽  
Ex Vivo ◽  
High Sensitivity ◽  
Optical Coherence ◽  
Cross Sectional ◽  
Neointimal Thickness ◽  
Stent Strut ◽  
Oct Imaging ◽  
Definition Of

Abstract Background In many studies, struts coverage is defined as >0 mm of tissue overlying the stent struts by optical coherence tomography (OCT). However, this definition has never been validated using histology as the “gold standard”. The present study sought to assess the appropriate cut-off value of neointimal thickness of stent strut coverage by OCT using histology. Methods OCT imaging was performed on 39 human coronary arteries with stents from 25 patients at autopsy. A total of 165 cross-sectional images from 46 stents were co-registered with histology. The optimal cut-off value of strut coverage by OCT was determined. Strut coverage by histology was defined as endothelial cells with at least underlying two layers of smooth muscle cells. Considering the resolution of OCT is 10–20 μm, 3 different cut-off values (i.e. at ≥20, ≥40, and ≥60 μm) were assessed. Results A total of 2235 struts were evaluated by histology. Eventually, 1216 struts which were well-matched struts were analyzed in this study. By histology, uncovered struts were observed in 160 struts and covered struts were observed in 1056 struts. The broadly used definition of OCT-coverage which does not consider neointimal thickness yielded a poor specificity of 37.5% and high sensitivity 100%. Of 3 cut-off values, the cut-off value of >40 μm was more accurate as compared to >20 and >60 mm [sensitivity (99.3%), specificity (91.0%), positive predictive value (98.6%), and negative predictive value (95.6%)] Conclusion The most accurate cut-off value was ≥40 μm neointimal thickness by OCT in order to identify stent strut coverage validated by histology. Funding Acknowledgement Type of funding source: None

scholarly journals Comparison between Widefield Optical Coherence Tomography Devices in Eyes with High Myopia

Diagnostics ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 658
Author(s):  
Federico Corvi ◽  
Federico Zicarelli ◽  
Matteo Airaldi ◽  
Salvatore Parrulli ◽  
Mariano Cozzi ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
High Myopia ◽  
Cross Sectional Study ◽  
Horizontal Line ◽  
Optical Coherence ◽  
Cross Sectional ◽  
Swept Source ◽  
Image Artifact ◽  
Control Subjects ◽  
And Control

Background: To compare four different optical coherence tomography (OCT) devices for visualization of retinal and subretinal layers in highly myopic eyes. Methods: In this prospective, observational, cross-sectional study, consecutive patients with high myopia and control subjects were imaged by four OCT devices: Spectralis OCT2, PlexElite 2.0 100 kHz, PlexElite 2.0 200 kHz and the Canon Xephilio OCT-S1. The acquisition protocol for comparison consisted of single vertical and horizontal line scans centered on the fovea. Comparison between the devices in the extent of visible retina, presence of conjugate image or mirror artifacts, visibility of the sclerochoroidal interface and retrobulbar tissue. Results: 30 eyes with high myopia and 30 control subjects were analyzed. The visualized RPE length was significantly different between the OCT devices with Xephilio OCT-S1 imaging the largest extent (p < 0.0001). The proportion of eyes with conjugate image artifact was significantly higher with the Spectralis OCT (p < 0.0001), and lower with the PlexElite 200 kHz (p < 0.0001). No difference in visibility of the sclerochoroidal interface was noted among instruments. The retrobulbar tissue was visible in a higher proportion of eyes using swept-source PlexElite 100 kHz and 200 kHz (p < 0.007) compared to the other devices. Conclusions: In highly myopic eyes, the four OCT devices demonstrated significant differences in the extent of the retina imaged, in the prevalence of conjugate image artifact, and in the visualization of the retrobulbar tissue.

Optical Coherence Tomography and Pattern Electroretinography Changes in Egyptian Patients with Major Depressive Disorder

QJM ◽  
2021 ◽  
Vol 114 (Supplement_1) ◽  
Author(s):  
Mostafa S ElShaarawi ◽  
Ayman A Gaafar ◽  
Hisham S. Saad Eldin ◽  
Randa H Ali
Keyword(s):  
Optical Coherence Tomography ◽  
Major Depressive Disorder ◽  
Depressive Disorder ◽  
Control Group ◽  
Ophthalmological Examination ◽  
Optical Coherence ◽  
Fiber Layer ◽  
Major Depressive ◽  
Cross Sectional ◽  
Pattern Electroretinography

Abstract Background Major depressive disorder (MDD) is a common psychiatric disorder that affects nearly 11.1-14.6 % of the population in their lifetime. Pathophysiology and brain imaging findings show that degenerative and inflammatory processes may play a role. Meta-analysis of voxel-based morphometry studies in MDD demonstrated significant gray matter loss. From anatomical and embryological perspectives, the retina can be considered a unique extension of the brain and is able to reflect axonal histopathology. Being unmyelinated, it can provide insight into the pathophysiological processes of diseases with a neurodegenerative element. Aim to compare retinal optical coherence tomography (OCT) parameters in a group of MDD patients with a healthy control group and to correlate OCT parameters with pattern electroretinography (PERG) parameters. Method a controlled cross sectional study was conducted on 30 MDD patients and 28 age and sex matched controls. Both groups had a full ophthalmological examination, OCT imaging and 7 patients and 11 controls have PERG recorded. Results Thinning of the superior retinal nerve fiber layer, thinning of most of the ganglion cell inner plexiform (GCIP) layer, thinning of most of the macular thickness and thinning of macular volume in both eyes were detected. There was a statistically significant positive correlation between the left GCIP layer and the amplitude of the N95 wave. Also a statistically significant negative correlation existed between MDD duration in years with the left eye's average volume of the outer ring of the macula. Conclusion Significant retinal changes were detected by OCT in MDD patients supporting the theory of neurodegeneration as a pathophysiology of MDD.

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