Cleveland Clinic

Machine Learning-Based Automated Detection and Quantification of Geographic Atrophy and Hypertransmission Defects Using Spectral Domain Optical Coherence Tomography

, , , , , , , , , , , , , ,

The current study describes the development and assessment of innovative, machine learning (ML)-based approaches for automated detection and pixel-accurate measurements of regions with geographic atrophy (GA) in late-stage age-related macular degeneration (AMD) using optical coherence tomography systems. 900 OCT volumes, 100266 B-scans, and en face OCT images from 341 non-exudative AMD patients with or without GA were included in this study from both Cirrus (Zeiss) and Spectralis (Heidelberg) OCT systems. B-scan and en face level ground truth GA masks were created on OCT B-scan where the segmented ellipsoid zone (EZ) line, retinal pigment epithelium (RPE) line, and bruchs membrane (BM) line overlapped. Two deep learning-based approaches, B-scan level and en face level, were trained. The OCT B-scan model had detection accuracy of 91% and GA area measurement accuracy of 94%. The en face OCT model had detection accuracy of 82% and GA area measurement accuracy of 96% with primary target...

Motion-tracking Brillouin microscopy for in-vivo corneal biomechanics mapping

, , ,

Corneal biomechanics play a critical role in maintaining corneal shape and thereby directly influence visual acuity. However, direct corneal biomechanical measurement in-vivo with sufficient accuracy and a high spatial resolution remains an open need. Here, we developed a three-dimensional (3D) motion-tracking Brillouin microscope for in-vivo corneal biomechanics mapping. The axial tracking utilized optical coherence tomography, which provided a tracking accuracy better than 3 µm. Meanwhile, 10 µm lateral tracking was achieved by tracking pupils with digital image processing. The 3D tracking enabled reconstruction of depth-dependent Brillouin distribution with a high spatial resolution. This superior technical performance enabled the capture of high-quality mechanical mapping in vivo even while the subject was breathing normally. Importantly, we improved Brillouin spectral measurements to achieve relative accuracy better than 0.07% verified by rubidium absorption frequencies, with 0...

Automated analysis of fibrous cap in intravascular optical coherence tomography images of coronary arteries

, , , , , , , , , , ,

Thin-cap fibroatheroma (TCFA) and plaque rupture have been recognized as the most frequent risk factor for thrombosis and acute coronary syndrome. Intravascular optical coherence tomography (IVOCT) can identify TCFA and assess cap thickness, which provides an opportunity to assess plaque vulnerability. We developed an automated method that can detect lipidous plaque and assess fibrous cap thickness in IVOCT images. This study analyzed a total of 4360 IVOCT image frames of 77 lesions among 41 patients. Expert cardiologists manually labeled lipidous plaque based on established criteria. To improve segmentation performance, preprocessing included lumen segmentation, pixel-shifting, and noise filtering on the raw polar (r, θ) IVOCT images. We used the DeepLab-v3 plus deep learning model to classify lipidous plaque pixels. After lipid detection, we automatically detected the outer border of the fibrous cap using a special dynamic programming algorithm and assessed the cap thickness...

A comprehensive update on the use of optical coherence tomography angiography in glaucoma

, , ,

Purpose: The primary purpose of this review is to provide a comprehensive summary on the technical principles of OCTA and to enumerate vascular parameters being explicated for glaucoma diagnosis and progression with emphasis on recent studies. In addition, the authors also summarize the future clinical potentials of OCTA in glaucoma and enumerate the limitations of this imaging modality in the present-day scenario. Methods: The index study is a narrative review on OCTA in glaucoma. The authors searched the PubMed database using the key phrases ''optical coherence tomography angiography" AND "glaucoma,'' AND/OR "vascular parameters" AND/OR "ocular perfusion." Being a relatively recent development in ocular imaging, studies in which OCTA imaging had been used for glaucoma evaluation since 2012 were included until March 2022. The literature search included original studies and previous review articles, while case reports were excluded. Preliminary search was based on relevant articles ...

OCT-Derived Radiomic Features Predict Anti–VEGF Response and Durability in Neovascular Age-Related Macular Degeneration

, , , , , , ,

No established biomarkers currently exist for therapeutic efficacy and durability of anti–VEGF therapy in neovascular age-related macular degeneration (nAMD). This study evaluated radiomic-based quantitative OCT biomarkers that may be predictive of anti-VEGF treatment response and durability. Design Assessment of baseline biomarkers using machine learning (ML) classifiers to predict tolerance to anti-VEGF therapy. Participants Eighty-one participants with treatment-naïve nAMD from the OSPREY study, including 15 super responders (patients who achieved and maintained retinal fluid resolution) and 66 non–super responders (patients who did not achieve or maintain retinal fluid resolution). Methods A total of 962 texture-based radiomic features were extracted from fluid, subretinal hyperreflective material (SHRM), and different retinal tissue compartments of OCT scans. The top 8 features, chosen by the minimum redundancy maximum relevance feature selection method, were e...

Intraoperative OCT Guidance of Intraocular Surgery (MIOCT)

Optical Coherence Tomography (OCT) is used to capture reproducible ocular morphology and cross-sectional tissue measurements in-vivo in a rapid, non-invasive, non-contact manner. It has displaced ophthalmoscopy and stereo photography for clinical assessment and documentation of retinal microanatomy including thickness, cystoid structures, subretinal fluid and retinal traction.(1) Spectral Domain Optical Coherence Tomography (SDOCT) has the speed and resolution required for real-time noninvasive three-dimensional imaging of critical pathology. While modern ophthalmic surgery has benefited from rapid advances in instrumentation and techniques (2-6), the basic principles of the stereo zoom operating microscope have not changed (except for increased automation) since the 1930's. (7-9) The ability to better resolve tissue microanatomy through real-time micro-imaging would have a dramatic impact on ophthalmic surgeon's capabilities, foster the development of new surgical techniques, and p...

Cleveland Clinic Receives NIH Grant for Broad Bandwidth Transducers for High Resolution Information Rich IVUS

Cleveland Clinic Received a 2022 NIH Grant for $390,345 for Broad Bandwidth Transducers for High Resolution Information Rich IVUS. The principal investigator is Aaron Fleischman. Below is a summary of the proposed work. Intra-coronary imaging is a powerful clinical tool for decision making, treatment planning, and assessment of stent deployment. It is also a powerful research tool for plaque progression/regression, drug treatments, and device interventions. There are clear advantages and disadvantages of common intravascular imaging methods. Intravascular ultrasound (IVUS) provides good resolution and allows one to measure lumen narrowing, wall thickening, atheroma burden, and to a lesser extent stent deployment. Using spectral analysis of the RF signal and machine learning, our group has developed software, which was later commercialized, to automatically classify atherosclerotic tissues using IVUS images. Intravascular optical coherence tomography (IVOCT) has better resolution tha...

Automated Machine Learning Detection of Hydroxychloroquine Toxicity and Prediction of Future Toxicity Using Higher Order OCT Biomarkers

, , , , , ,

Objective: Despite guidelines for HCQ toxicity screening, there are clear challenges to accurate detecting and interpretation. In the current report, the feasibility of automated machine-learning (ML) -based detection of hydroxychloroquine (HCQ) retinopathy and prediction of progression to toxicity in eyes without preexisting toxicity is described. Design: Retrospective longitudinal cohort study. Subjects and methods: This was an IRB-approved retrospective longitudinal image analysis study of 388 subjects on hydroxychloroquine. Multi-layer compartmental retinal segmentation with EZ mapping was utilized to harvest quantitative SDOCT biomarkers. Utilizing a combination of clinical features (i.e., cumulative HCQ dose, duration of therapy) and quantitative imaging biomarkers (e.g., volumetric ellipsoid zone (EZ) integrity and compartmental measurements), machine learning models were created to detect toxicity and predict progression based on ground truth OCT-based toxicity reads by 2 ma...

The Role of Optical Coherence Tomography and Optical Coherence Tomography Angiography in the Differential Diagnosis of Posterior Uveitis

,

Purpose: Modalities such as optical coherence tomography (OCT) and OCT angiography (OCTA) have improved the diagnostic utility of fundus imaging in management of uveitis. The purpose of this study is to review role of OCT and OCTA in differential diagnosis of certain posterior uveitic entities. Methods: Narrative review. Results: In this review, we have comprehensively summarized the utility of OCT and OCTA in helping the clinician diagnose common but challenging inflammatory conditions including ocular toxoplasmosis, viral retinitis, and vitreoretinal lymphoma, among others. OCT and OCTA can also be used to assess the choriocapillaris involvement in conditions such as multiple evanescent white dot syndrome, and choroidal granulomas in tubercular and sarcoid uveitis. Conclusions: Fundus imaging with OCT and OCTA has assumed a significant role in establishing the diagnosis in uveitis apart from microbiological and other laboratory analysis. Advantages such as rapidity and non-invasiv...

Impact of Baseline Quantitative OCT Features on Response to Risuteganib for the Treatment of Dry AMD-The Importance of Outer Retinal Integrity

, , , , , , , , ,

Objective: The purpose of the study was to perform a post-hoc analysis to explore the effect of baseline anatomic characteristics identified on optical coherence tomography (OCT) on best-corrected visual acuity (BCVA) response with risuteganib from the completed Phase 2 study in subjects with dry age-related macular degeneration. Design: Post-hoc analysis of a randomized, double-masked, placebo-controlled Phase 2 study SUBJECTS, PARTICIPANTS, AND/OR CONTROLS: Eyes with intermediate dry AMD with BCVA between 20/40-20/200. Patients with concurrent vision impacting or macula obscuring ocular pathology were excluded. Methods: Patients were randomized to receive intravitreal 1.0 mg ristuteganib or sham injection at baseline. A second 1.0mg intravitreal injection of risuteganib was given at week 16 in the treatment arm. Two independent masked reading centers evaluated baseline anatomic characteristics on OCT to explore for features associated with positive response to risuteganib. Main ou...

Effect of Evolocumab on Coronary Plaque Phenotype and Burden in Statin-Treated Patients Following Myocardial Infarction

, , , , , , , , , , , , , , , ,

Objectives The purpose of this study was to determine the effect of evolocumab on optical coherence tomography (OCT) measures of plaque composition. Background The proprotein convertase subtilisin kexin type-9 inhibitor evolocumab produced coronary atheroma regression in statin-treated patients. Methods Patients with a non–ST-segment elevation myocardial infarction were treated with monthly evolocumab 420 mg (n = 80) or placebo (n = 81) for 52 weeks. Patients underwent serial OCT and intravascular ultrasound imaging within a matched arterial segment of a nonculprit vessel. The primary analysis determined the change in the minimum fibrous cap thickness and maximum lipid arc throughout the imaged arterial segment. Additional analyses determined changes in OCT features in lipid-rich plaque regions and plaque burden. Safety and tolerability were evaluated. Results Among treated patients, (age 60.5 ± 9.6 years; 28.6% women; low-density lipoprotein cholesterol [LDL-C], 141.3 ...

Grading Anterior Chamber Inflammation with Anterior Segment Optical Coherence Tomography: An Overview

, , , , , ,

The objective grading of anterior chamber inflammation (ACI) has remained a challenge in the field of uveitis. While the grading criteria produced by the Standardization of Uveitis Nomenclature (SUN) International Workshop have been widely adopted, limitations exist including interobserver variability and grading confined to discrete categories rather than a continuous measurement. Since the earliest iterations of optical coherence tomography (OCT), ACI has been assessed using anterior segment OCT and shown to correlate with slit-lamp findings. However, widespread use of this approach has not been adopted. Barriers to standardization include variability in OCT devices across clinical settings, lack of standardization of image acquisition protocols, varying quantification methods, and the difficulty of distinguishing inflammatory cells from other cell types. Modern OCT devices and techniques in artificial intelligence show promise in expanding the clinical applicability of anterior s...

Plaque microstructures during metformin therapy in type 2 diabetic subjects with coronary artery disease: optical coherence tomography analysis

, , , , , , ,

Background: While metformin is recommended as a first-line cardioprotective therapy for type 2 diabetic patients, whether it exerts direct effects on atherosclerotic plaque remains uncertain. The current study characterized coronary plaque microstructures in type 2 diabetic patients who received metformin. Methods: We retrospectively analyzed 409 non-culprit lipid plaques in 313 type 2 diabetic patients with coronary artery disease (CAD) by using frequency-domain optical coherence tomography (FD-OCT) imaging. FD-OCT derived plaque microstructures were compared in patients stratified according to metformin use. Results: A proportion of 38.6% of study subjects received metformin. Patients receiving metformin more likely exhibited a history of hypertension (79.3% vs . 67.1%, P=0.03) and metabolic syndrome (52.8% vs . 36.4%, P=0.01). On FD-OCT imaging, the prevalence of lipid plaque was lower in the metformin group (66.2% vs . 77.9%, P=0.03). Furthermore, the metformin group demonstrate...

Optical Coherence Tomography Findings in Infectious Posterior Uveitis

, , , , , ,

Purpose To describe and illustrate the main optical coherence tomography (OCT) findings of infectious uveitis. Methods Narrative review. Results Posterior segment OCT in patients with infectious uveitis reveals posterior hyaloid face precipitates, superficial retinal precipitates and infiltrates, foveolitis, retinitis, neuro-retinitis, choroidal granulomas, and choroiditis as main imaging biomarkers. Some of these features are specific to the underlying causing etiology and may support the diagnosis and the initiation of treatment. Some OCT features disappear completely with resolution; some others are associated with irreversible retinal damage. Conclusions OCT identifies different features of infectious uveitis into the vitreous, the retina, and the choroid. OCT characteristics, combined with other multimodal imaging features, are helpful in the differential diagnosis of infectious uveitis, the early detection of complications, and the assessment of the response to therapy. ( ...

Utilization of deep learning to quantify fluid volume of neovascular age-related macular degeneration patients based on swept-source OCT imaging: The ONTARIO study

, , , , , ,

Purpose: To evaluate the predictive ability of a deep learning-based algorithm to determine long-term best-corrected distance visual acuity (BCVA) outcomes in neovascular age-related macular degeneration (nARMD) patients using baseline swept-source optical coherence tomography (SS-OCT) and OCT-angiography (OCT-A) data. Methods: In this phase IV, retrospective, proof of concept, single center study, SS-OCT data from 17 previously treated nARMD eyes was used to assess retinal layer thicknesses, as well as quantify intraretinal fluid (IRF), subretinal fluid (SRF), and serous pigment epithelium detachments (PEDs) using a novel deep learning-based, macular fluid segmentation algorithm. Baseline OCT and OCT-A morphological features and fluid measurements were correlated using the Pearson correlation coefficient (PCC) to changes in BCVA from baseline to week 52. Results: Total retinal fluid (IRF, SRF and PED) volume at baseline had the strongest correlation to improvement in BCVA at month ...

Categories

Organizations in the News

OCT Companies in the News

Picture Gallery