An Optimal Spatiotemporal Noise Filter for NI/OCT Imaging

Dynamic optical coherence tomography (D-OCT) is a relatively new technique that may be used to study the substructures in the retina, in the skin and its microcirculation. Furthermore, D-OCT is a validated method of imaging blood flow in skin microcirculation. The skin around venous and mixed arterio-venous ulcers was imaged and found to have tortuous vessels assumed to be angiogenic sprouts, and classified as dots, blobs, coils, clumps, lines, and curves. When these images were analyzed and measurements of vessel density were made, it was observed that the prevalence of coils and clumps in wound borders was significantly greater compared with those at wound centers. This reinforced the belief of inward growth of vessels from wound edge toward wound center which, in turn, reposed confidence in following the wound edge to study healing. D-OCT imaging permits the structure and the function of the microcirculation to be imaged, and vessel density measured. This offers a new vista of skin microcirculation and using it, to better understand angiogenesis in chronic wounds.

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42.3: Compact Design of Holographic Augmented Reality Display Using Bragg Grating Noise Filter and Holographic Lens

SID Symposium Digest of Technical Papers ◽

10.1002/sdtp.14464 ◽

2021 ◽

Vol 52 (S1) ◽

pp. 288-289

Author(s):

Kiseung Bang ◽

Byoungho Lee

Keyword(s):

Augmented Reality ◽

Bragg Grating ◽

Noise Filter ◽

Compact Design ◽

Holographic Lens

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Feasibility and Clinical Utility of Ultra-Widefield–Navigated Swept-Source Optical Coherence Tomography Imaging

Journal of VitreoRetinal Diseases ◽

10.1177/2474126421997335 ◽

2021 ◽

pp. 247412642199733

Author(s):

Kyle D. Kovacs ◽

M. Abdallah Mahrous ◽

Luis Gonzalez ◽

Benjamin E. Botsford ◽

Tamara L. Lenis ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Clinical Utility ◽

Clinical Decision Making ◽

Imaging System ◽

Imaging Modality ◽

Case Series ◽

Subretinal Fluid ◽

Optical Coherence ◽

Swept Source ◽

Oct Imaging

Purpose: This work aims to evaluate the clinical utility and feasibility of a novel scanning laser ophthalmoscope-based navigated ultra-widefield swept-source optical coherence tomography (UWF SS-OCT) imaging system. Methods: A retrospective, single-center, consecutive case series evaluated patients between September 2019 and October 2020 with UWF SS-OCT (modified Optos P200TxE, Optos PLC) as part of routine retinal care. The logistics of image acquisition, interpretability of images captured, nature of the peripheral abnormality, and clinical utility in management decisions were recorded. Results: Eighty-two eyes from 72 patients were included. Patients were aged 59.4 ± 17.1 years (range, 8-87 years). During imaging, 4.4 series of images were obtained in 4.1 minutes, with 86.4% of the image series deemed to be diagnostic of the peripheral pathology on blinded image review. The most common pathologic findings were chorioretinal scars (18 eyes). In 31 (38%) eyes, these images were meaningful in supporting clinical decision-making with definitive findings. Diagnoses imaged included retinal detachment combined with retinoschisis, retinal hole with overlying vitreous traction and subretinal fluid, vitreous inflammation overlying a peripheral scar, Coats disease, and peripheral retinal traction in sickle cell retinopathy. Conclusions: Navigated UWF SS-OCT imaging was clinically practical and provided high-quality characterization of peripheral retinal lesions for all eyes. Images directly contributed to management plans, including laser, injection or surgical treatment, for a clinically meaningful set of patients (38%). Future studies are needed to further assess the value of this imaging modality and its role in diagnosing, monitoring, and treating peripheral lesions.

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Feasibility of peripheral OCT imaging using a novel integrated SLO ultra-widefield imaging swept-source OCT device

International Ophthalmology ◽

10.1007/s10792-021-01837-7 ◽

2021 ◽

Author(s):

Simrat K. Sodhi ◽

John Golding ◽

Carmelina Trimboli ◽

Netan Choudhry

Keyword(s):

Posterior Pole ◽

Field Of View ◽

Retinal Diseases ◽

Swept Source ◽

Full Field ◽

Swept Source Oct ◽

Oct Imaging ◽

Field Device ◽

Areas Of Interest ◽

Retinal Pathologies

Abstract Purpose To describe the feasibility of peripheral OCT imaging in retinal diseases using a novel full-field device. Methods A total of 134 consecutive eyes were referred and imaged on the Optos Silverstone swept-source OCT (SS-OCT) (Optos PLC; Dunfermline, UK). Scanning laser ophthalmoscope (SLO) images and the associated SS-OCT images were obtained in the posterior pole, mid-periphery or far periphery based on the nature of the referral and on new areas of interest observed in the optomap images at the time of imaging. Results A total of 134 eyes (96 patients) were enrolled in the study. One hundred and twenty-five eyes (91 patients) with 38 retinal pathologies were prospectively assessed and 9 eyes (5 patients) were excluded due to incomplete image acquisition. The average age of the subjects was 54 years (range 21–92 years). Thirty-nine out of 125 eyes (31%) had macular pathologies. Eighty-six out of 125 eyes (69%) had peripheral only pathologies, an area which cannot be visualized by standard OCT devices with a 50 degree field-of-view. Conclusions The ability to capture peripheral pathologies using an integrated SLO-UWF imaging with full-field swept-source provided high-grade anatomical insight that confirmed the medical and surgical management in a majority of cases. Its use in the mid- and far periphery provides a holistic clinical picture, which can potentially aid in the understanding of various retinal pathologies.

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Optical Coherence Tomography of Peri-Ocular Skin Cancers: An Optical Biopsy

Ocular Oncology and Pathology ◽

10.1159/000511188 ◽

2020 ◽

pp. 1-9

Author(s):

Sabrina Bergeron ◽

Bryan Arthurs ◽

Debra-Meghan Sanft ◽

Christina Mastromonaco ◽

Miguel N. Burnier Jr.

Keyword(s):

Squamous Cell Carcinoma ◽

Optical Coherence Tomography ◽

Basal Cell Carcinoma ◽

Cell Carcinoma ◽

Squamous Cell ◽

Basal Cell ◽

Skin Lesions ◽

Sebaceous Carcinoma ◽

Optical Coherence ◽

Oct Imaging

Introduction: Optical coherence tomography (OCT) imaging has been used as a diagnostic tool for retinal disease for several years, and OCT apparatuses are becoming increasingly powerful. However, OCT has yet to reach its full potential in ophthalmology clinics. Alike retinal layers, it has been shown that OCT is able to generate cross-sectional images of the skin and allows visualization of skin lesions in a histopathology-like manner. Objective: We aim to validate OCT as an imaging modality for peri-ocular skin cancer. Through a series of cases, we highlight findings for 3 common eyelid malignancies: basal cell carcinoma, squamous cell carcinoma and sebaceous carcinoma. We propose an OCT image-based signature for basal cell carcinoma. Methods: This is a prospective study. Fifty-eight lesions suspicious of malignancy from 57 patients were subjected to OCT imaging prior to the surgical excision of the lesion. OCT images were analysed and scored according to previously identified OCT features. Eight representative examples are presented, highlighting the OCT patterns for each malignancy side by side to its corresponding histopathological sections. Results: Out of the 58 lesions analysed, 53 were malignant. A loss of the dermal-epidermal junction is observed in all malignant lesions. A strong link is observed between the presence of subepithelial hyporeflective nests on OCT and the diagnosis of basal cell carcinoma (present in 83% of cases). Conversely, lesions of epithelial origin such as squamous cell carcinoma are most often represented on OCT by acanthosis. Two supplementary cases, one basal cell carcinoma and one sebaceous carcinoma, are provided to illustrate how OCT imaging is a valuable tool in cases where clinical observations may be unusual. Conclusions: We provide evidence supporting the use of OCT for the evaluation of peri-ocular cancers. OCT enables visualization of the skin layers in vivo, before biopsy. Our results show that certain OCT features can contribute to include or exclude a diagnosis of basal cell carcinoma. By integrating this non-invasive imaging methodology into the routine assessment of peri-ocular skin lesions, especially in health care centres where access to specialists is limited, OCT imaging can increase clinical precision, reduce delays in patient referral and enhance patient care.

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Optical coherence tomography for elucidation of flow-diversion phenomena: The concept of endothelized mural thrombus behind reversible in-stent stenosis in flow-diverters

Interventional Neuroradiology ◽

10.1177/15910199211003432 ◽

2021 ◽

pp. 159101992110034

Author(s):

Andre Monteiro ◽

Demetrius K Lopes ◽

Amin Aghaebrahim ◽

Ricardo Hanel

Keyword(s):

Optical Coherence Tomography ◽

Intracranial Aneurysms ◽

Flow Diversion ◽

Optical Coherence ◽

Recurrence Rates ◽

Oct Imaging ◽

Intravascular Optical Coherence Tomography ◽

Stenotic Area ◽

Flow Diverters ◽

Stent Stenosis

Purpose Flow-diverters have revolutionized the endovascular treatment of intracranial aneurysms, offering a durable solution to aneurysms with high recurrence rates after conventional stent-assisted coiling. Events that occur after treatment with flow-diversion, such as in-stent stenosis (ISS) are not well understood and require further assessment. After assessing an animal model with Optical Coherence Tomography (OCT), we propose a concept that could explain the mechanism causing reversible ISS after treatment of intracranial aneurysms with flow-diverters. Methods Six Pipeline Flex embolization devices (PED-Flex), six PED with Shield technology (PED-Shield), and four Solitaire AB devices were implanted in the carotid arteries (two stents per vessel) of four pigs. Intravascular optical coherence tomography (OCT) and digital subtraction angiography (DSA) images obtained on day 21 were compared to histological specimens. Results A case of ISS in a PED-Flex device was assessed with OCT imaging. Neointima with asymmetrical topography completely covering the PED struts was observed. Histological preparations of the stenotic area demonstrated thrombus on the surface of device struts, covered by neointima. Conclusion This study provides a plausible concept for reversible ISS in flow-diverters. Based on an observation of a previous experiment, we propose that similar cases of ISS are related to thrombus presence underneath endothelization, but further experiments focused on this phenomenon are needed. Optical Coherence Tomography will be useful tool when available for clinical use.

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Synthetic polarization-sensitive optical coherence tomography by deep learning

npj Digital Medicine ◽

10.1038/s41746-021-00475-8 ◽

2021 ◽

Vol 4 (1) ◽

Author(s):

Yi Sun ◽

Jianfeng Wang ◽

Jindou Shi ◽

Stephen A. Boppart

Keyword(s):

Optical Coherence Tomography ◽

Deep Learning ◽

Imaging System ◽

Imaging Modality ◽

Similarity Index ◽

Polarization Sensitivity ◽

Imaging Method ◽

Optical Coherence ◽

The Real ◽

Oct Imaging

AbstractPolarization-sensitive optical coherence tomography (PS-OCT) is a high-resolution label-free optical biomedical imaging modality that is sensitive to the microstructural architecture in tissue that gives rise to form birefringence, such as collagen or muscle fibers. To enable polarization sensitivity in an OCT system, however, requires additional hardware and complexity. We developed a deep-learning method to synthesize PS-OCT images by training a generative adversarial network (GAN) on OCT intensity and PS-OCT images. The synthesis accuracy was first evaluated by the structural similarity index (SSIM) between the synthetic and real PS-OCT images. Furthermore, the effectiveness of the computational PS-OCT images was validated by separately training two image classifiers using the real and synthetic PS-OCT images for cancer/normal classification. The similar classification results of the two trained classifiers demonstrate that the predicted PS-OCT images can be potentially used interchangeably in cancer diagnosis applications. In addition, we applied the trained GAN models on OCT images collected from a separate OCT imaging system, and the synthetic PS-OCT images correlate well with the real PS-OCT image collected from the same sample sites using the PS-OCT imaging system. This computational PS-OCT imaging method has the potential to reduce the cost, complexity, and need for hardware-based PS-OCT imaging systems.

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