scholarly journals Axial Motion Compensation Of Optical Coherence Tomography With A Collaborative Medical Robot

2021 ◽  
Author(s):  
Robnier Reyes Perez
Keyword(s):  
Optical Coherence Tomography ◽  
Motion Compensation ◽  
Imaging System ◽  
Imaging Modality ◽  
Tumor Resection ◽  
Optic Axis ◽  
Robotic Arm ◽  
Optical Coherence ◽  
Axial Motion ◽  
Oct Imaging

This thesis presents an imaging tool consisting of an Optical Coherence Tomography (OCT) imaging system mounted on a collaborative robotic arm to enable axial motion compensation. Optical Coherence Tomography is a subsurface, high-resolution imaging modality used in neuroimaging to differentiate between pathological and non-pathological tissue. The motivation behind this project is to bring Optical Coherence Tomography to the operating room for neuroimaging to help with cancerous tissue differentiation and maximize the extent of tumor resection. However, neurosurgeons have expressed concern with respect to intracranial pressure (ICP) pulsation displacing the brain far off the optic axis of the imaging system so as to not be visible. The collaborative robotic arm compensates for sample motion along the optic axis using a Proportional controller to track the position of the peak intensity of the sample’s intensity profile, which generally corresponds to the sample surface. Collaborative robots have changed the robot industry paradigm becoming increasingly functional and safer than the previous generations of robotic arms. We present an OCT robot end-effector to test the feasibility of performing OCT imaging with the collaborative robot.

scholarly journals Axial Motion Compensation Of Optical Coherence Tomography With A Collaborative Medical Robot

2021 ◽  
Author(s):  
Robnier Reyes Perez
Keyword(s):  
Optical Coherence Tomography ◽  
Motion Compensation ◽  
Imaging System ◽  
Imaging Modality ◽  
Tumor Resection ◽  
Optic Axis ◽  
Robotic Arm ◽  
Optical Coherence ◽  
Axial Motion ◽  
Oct Imaging

This thesis presents an imaging tool consisting of an Optical Coherence Tomography (OCT) imaging system mounted on a collaborative robotic arm to enable axial motion compensation. Optical Coherence Tomography is a subsurface, high-resolution imaging modality used in neuroimaging to differentiate between pathological and non-pathological tissue. The motivation behind this project is to bring Optical Coherence Tomography to the operating room for neuroimaging to help with cancerous tissue differentiation and maximize the extent of tumor resection. However, neurosurgeons have expressed concern with respect to intracranial pressure (ICP) pulsation displacing the brain far off the optic axis of the imaging system so as to not be visible. The collaborative robotic arm compensates for sample motion along the optic axis using a Proportional controller to track the position of the peak intensity of the sample’s intensity profile, which generally corresponds to the sample surface. Collaborative robots have changed the robot industry paradigm becoming increasingly functional and safer than the previous generations of robotic arms. We present an OCT robot end-effector to test the feasibility of performing OCT imaging with the collaborative robot.

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

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.

scholarly journals Synthetic polarization-sensitive optical coherence tomography by deep learning

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.

scholarly journals Optical Coherence Tomography

2007 ◽  
Vol 7 ◽  
pp. 87-108 ◽  
Author(s):  
Pier Alberto Testoni
Keyword(s):  
Optical Coherence Tomography ◽  
Gastrointestinal Tract ◽  
Ultrasound Imaging ◽  
Imaging Modality ◽  
Infrared Light ◽  
Optical Coherence ◽  
Depth Of Penetration ◽  
Ductal System ◽  
Neoplastic Lesions ◽  
Oct Imaging

Optical coherence tomography (OCT) is an optical imaging modality that performs high-resolution, cross-sectional, subsurface tomographic imaging of the microstructure of tissues. The physical principle of OCT is similar to that of B-mode ultrasound imaging, except that it uses infrared light waves rather than acoustic waves. Thein vivoresolution is 10–25 times better (about 10 µm) than with high-frequency ultrasound imaging, but the depth of penetration is limited to 1–3 mm, depending on tissue structure, depth of focus of the probe used, and pressure applied to the tissue surface. In the last decade, OCT technology has evolved from an experimental laboratory tool to a new diagnostic imaging modality with a wide spectrum of clinical applications in medical practice, including the gastrointestinal tract and pancreatico-biliary ductal system. OCT imaging from the gastrointestinal tract can be done in humans by using narrow-diameter, catheter-based probes that can be inserted through the accessory channel of either a conventional front-view endoscope, for investigating the epithelial structure of the gastrointestinal tract, or a side-view endoscope, inside a standard transparent ERCP (endoscopic retrograde cholangiopancreatography) catheter, for investigating the pancreatico-biliary ductal system. The esophagus and esophagogastric junction have been the most widely investigated organs so far; more recently, duodenum, colon, and the pancreatico-biliary ductal system have also been extensively investigated. OCT imaging of the gastrointestinal wall structure is characterized by a multiple-layer architecture that permits an accurate evaluation of the mucosa, lamina propria, muscularis mucosae, and part of the submucosa. The technique may therefore be used to identify preneoplastic conditions of the gastrointestinal tract, such as Barrett's epithelium and dysplasia, and evaluate the depth of penetration of early-stage neoplastic lesions. OCT imaging of the pancreatic and biliary ductal system could improve the diagnostic accuracy for ductal epithelial changes, and the differential diagnosis between neoplastic and non-neoplastic lesions.

scholarly journals Optical coherence tomography in varying aetiologies of renal artery stenosis: a case series

2019 ◽  
Vol 3 (2) ◽  
Author(s):  
Rajesh Vijayvergiya ◽  
Kewal Kanabar ◽  
Darshan Krishnappa ◽  
Ganesh Kasinadhuni ◽  
Ashish Sharma ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Renal Artery ◽  
Renal Artery Stenosis ◽  
Imaging Modality ◽  
Case Reports ◽  
Case Series ◽  
Artery Stenosis ◽  
Optical Coherence ◽  
Renal Angioplasty ◽  
Oct Imaging

Abstract Background Renal artery stenosis (RAS) is a common cause of secondary hypertension. The most common aetiology is atherosclerosis; however, other causes like fibromuscular dysplasia (FMD) and Takayasu arteritis (TA) are also frequently encountered. The lesion characteristics and its response to percutaneous intervention depend upon the aetiology of RAS. Optical coherence tomography (OCT) is an excellent imaging modality to analyse coronary lesions during percutaneous coronary interventions. The data regarding the utility of OCT in renal artery imaging is limited, consisting of a few case reports. Case summary We hereby report four cases of RAS, each of different aetiology (atherosclerotic, FMD, post-transplant, and TA), who underwent OCT imaging of the renal artery along with percutaneous renal angioplasty. Discussion The advantages of OCT imaging include demonstration of the arterial wall, pathological features of the disease, and to guide percutaneous interventions. The major limitation of OCT is its lower imaging depth, which may render imaging of large vessels difficult.

scholarly journals 3D Curvelet-Based Segmentation and Quantification of Drusen in Optical Coherence Tomography Images

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
M. Esmaeili ◽  
A. M. Dehnavi ◽  
H. Rabbani
Keyword(s):  
Optical Coherence Tomography ◽  
Imaging System ◽  
Imaging Modality ◽  
Age Related Macular Degeneration ◽  
Spectral Domain ◽  
Optical Coherence ◽  
Treatment Protocols ◽  
Age Related ◽  
Sd Oct

Spectral-Domain Optical Coherence Tomography (SD-OCT) is a widely used interferometric diagnostic technique in ophthalmology that provides novel in vivo information of depth-resolved inner and outer retinal structures. This imaging modality can assist clinicians in monitoring the progression of Age-related Macular Degeneration (AMD) by providing high-resolution visualization of drusen. Quantitative tools for assessing drusen volume that are indicative of AMD progression may lead to appropriate metrics for selecting treatment protocols. To address this need, a fully automated algorithm was developed to segment drusen area and volume from SD-OCT images. The proposed algorithm consists of three parts: (1) preprocessing, which includes creating binary mask and removing possible highly reflective posterior hyaloid that is used in accurate detection of inner segment/outer segment (IS/OS) junction layer and Bruch’s membrane (BM) retinal layers; (2) coarse segmentation, in which 3D curvelet transform and graph theory are employed to get the possible candidate drusenoid regions; (3) fine segmentation, in which morphological operators are used to remove falsely extracted elongated structures and get the refined segmentation results. The proposed method was evaluated in 20 publically available volumetric scans acquired by using Bioptigen spectral-domain ophthalmic imaging system. The average true positive and false positive volume fractions (TPVF and FPVF) for the segmentation of drusenoid regions were found to be 89.15% ± 3.76 and 0.17% ± .18%, respectively.

scholarly journals Morpho-molecular ex vivo detection and grading of non-muscle-invasive bladder cancer using forward imaging probe based multimodal optical coherence tomography and Raman spectroscopy

The Analyst ◽  
2020 ◽  
Vol 145 (4) ◽  
pp. 1445-1456 ◽  
Author(s):  
Fabian Placzek ◽  
Eliana Cordero Bautista ◽  
Simon Kretschmer ◽  
Lara M. Wurster ◽  
Florian Knorr ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Optical Coherence Tomography ◽  
Imaging System ◽  
Ex Vivo ◽  
Large Field ◽  
Optical Coherence ◽  
Fiber Optic Probe ◽  
Optic Probe ◽  
Muscle Invasive

Characterization of bladder biopsies, using a combined fiber optic probe-based optical coherence tomography and Raman spectroscopy imaging system that allows a large field-of-view imaging and detection and grading of cancerous bladder lesions.

Blood Vessel Density Measured Using Dynamic Optical Coherence Tomography is a Tool for Wound Healers

2021 ◽  
pp. 153473462110173
Author(s):  
Rajgopal Mani ◽  
Jon Holmes ◽  
Kittipan Rerkasem ◽  
Nikolaos Papanas
Keyword(s):  
Blood Flow ◽  
Optical Coherence Tomography ◽  
Blood Vessel ◽  
Chronic Wounds ◽  
Vessel Density ◽  
Optical Coherence ◽  
Skin Microcirculation ◽  
Wound Edge ◽  
Venous Ulcers ◽  
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.

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

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

<b><i>Introduction:</i></b> 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. <b><i>Objective:</i></b> 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. <b><i>Methods:</i></b> 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. <b><i>Results:</i></b> 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. <b><i>Conclusions:</i></b> 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.

Sign in / Sign up

Export Citation Format

Share Document