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    1. An Overview of OCT Techniques for Detection of Ophthalmic Syndromes

      An Overview of OCT Techniques for Detection of Ophthalmic Syndromes

      The retina is an essential part of the human eye. It is a very small part at the subsequent pole of the human eye, and it is composed of a tissue cell that can detect the presence of light. The tissue is sensitive enough to detect the amount of light present, its intensity, and a range of different wavelengths as well. These tissues generate nerve signals, and those signals are passed to the brain via the optic nerve. If the retina malfunctions, then different retinal disorders can occur such as diabetic retinopathy, glaucoma, and pathologic myopia. These can be considered ...

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    2. The diagnostic value of optical coherence tomography angiography in diabetic retinopathy: a systematic review

      The diagnostic value of optical coherence tomography angiography in diabetic retinopathy: a systematic review

      Purpose Diabetic retinopathy (DR) is one of the leading causes of blindness worldwide. Accurate investigative tools are essential for the early diagnosis and monitoring of the disease. Optical coherence tomography angiography (OCTA) is a recently developed technology that enables visualisation of the retinal microvasculature. Methods A systematic review of the literature was performed to examine the diagnostic use of OCTA in DR to date. Medline, EMBASE, and Cochrane databases were searched to find relevant studies. Sixty-one original studies were selected for the review. Results and discussion OCTA has demonstrated the ability to identify microvascular features of DR such as microaneurysms ...

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    3. Colocalization of neurons in optical coherence microscopy and Nissl-stained histology in Brodmann’s area 32 and area 21

      Colocalization of neurons in optical coherence microscopy and Nissl-stained histology in Brodmann’s area 32 and area 21

      Optical coherence tomography is an optical technique that uses backscattered light to highlight intrinsic structure, and when applied to brain tissue, it can resolve cortical layers and fiber bundles. Optical coherence microscopy (OCM) is higher resolution (i.e., 1.25 µm) and is capable of detecting neurons. In a previous report, we compared the correspondence of OCM acquired imaging of neurons with traditional Nissl stained histology in entorhinal cortex layer II. In the current method-oriented study, we aimed to determine the colocalization success rate between OCM and Nissl in other brain cortical areas with different laminar arrangements and cell packing ...

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    4. Deep Learning-Based Detection and Segmentation for BVS Struts in IVOCT Images

      Deep Learning-Based Detection and Segmentation for BVS Struts in IVOCT Images

      Bioresorbable Vascular Scaffold (BVS) is the latest stent type for the treatment of coronary artery disease. A major challenge of BVS is that once it is malapposed during implantation, it may potentially increase the risks of late stent thrombosis. Therefore it is important to analyze struts malapposition during implantation. This paper presents an automatic method for BVS malapposition analysis in intravascular optical coherence tomography images. Struts are firstly detected by a detector trained through deep learning. Then, struts boundaries are segmented using dynamic programming. Based on the segmentation, apposed and malapposed struts are discriminated automatically. Experimental results show that the ...

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    5. Plaque modification of severely calcified coronary lesions by scoring balloon angioplasty using Lacrosse non-slip element: insights from an optical coherence tomography evaluation

      Plaque modification of severely calcified coronary lesions by scoring balloon angioplasty using Lacrosse non-slip element: insights from an optical coherence tomography evaluation

      Percutaneous coronary intervention (PCI) for heavily calcified lesions is challenging because these lesions are resistant to balloon dilatation and stenting. Lacrosse non-slip element (NSE) may have the potential to dilate heavily calcified lesions. We aimed to investigate predictors of successful lesion modification using Lacrosse NSE angioplasty via optical coherence tomography (OCT)-guided PCI. We investigated 32 patients with severe target lesion calcification treated with OCT-guided PCI. Successful lesion modification was defined as the complete fracture of calcification after Lacrosse NSE angioplasty. Before PCI, 172 segments with calcification were identified. After pre-dilatation using Lacrosse NSE, successful lesion modification was achieved in ...

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    6. Mitigation of Speckle Noise in Optical Coherence Tomograms

      Mitigation of Speckle Noise in Optical Coherence Tomograms

      Optical Coherence Tomography (OCT) is a promising high-resolution imaging technique that works based on low coherent interferometry. However, like other low coherent imaging modalities, OCT suffers from an artifact called, speckle. Speckle reduces the detectability of diagnostically relevant features in the tissue. Retinal optical coherence tomograms are of a great importance in detecting and diagnosing eye diseases. Different hardware or software based techniques are devised in literatures to mitigate speckle noise. The ultimate aim of any software-based despeckling technique is to suppress the noise part of speckle while preserves the information carrying portion of that. In this chapter, we reviewed ...

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    7. Phenotyping of Mouse Models with OCT

      Phenotyping of Mouse Models with OCT

      Optical coherence tomography (OCT) is an invaluable technique to perform noninvasive retinal imaging in small animal models such as mice. It provides virtual cross sections that correlate well with histomorphometric data with the advantage that multiple iterative measurements can be acquired in timeline analyses to detect dynamic changes and reduce the number of animals needed per study.

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    8. Coil embolization of pseudoaneurysm as a complication of excimer laser coronary angioplasty: insights from intravascular ultrasound and optical coherence tomography findings

      Coil embolization of pseudoaneurysm as a complication of excimer laser coronary angioplasty: insights from intravascular ultrasound and optical coherence tomography findings

      The occurrence of pseudoaneurysm in the coronary artery is rare and can develop after percutaneous coronary interventions. To date, the optimal therapy, including conservative, surgical, and endovascular therapies, for pseudoaneurysm in the coronary artery remains unclear. Here, we report a case of pseudoaneurysm arising as a complication of excimer laser coronary angioplasty, which was successfully treated with stent-assisted coil embolization, after which optical coherence tomography revealed complete healing of the pseudoaneurysm. This report highlights the feasibility of stent-assisted coil embolization for coronary pseudoaneurysms involving bifurcation.

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    9. Automated segmentation of en face choroidal images obtained by optical coherent tomography by machine learning

      Automated segmentation of en face choroidal images obtained by optical coherent tomography by machine learning

      Purpose To develop an automated method to segment the choroidal layers of en face optical coherent tomography (OCT) images by machine learning. Study design A cross-sectional, prospective study of 276 eyes of 181 healthy subjects. Methods OCT en face images of the choroid were obtained every 2.6 μm from the retinal pigment epithelium (RPE) to the chorioscleral border. The images at the start of the choriocapillaris, start of Sattler’s layer, and start of Haller’s layer were identified, and the image numbers from the RPE line were taken as the teacher data. Forty-one feature quantities of each image ...

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      Mentions: Taiji Sakamoto
    10. Morphological characteristics of optical coherence tomography defined plaque fissure in patients with acute coronary syndrome

      Morphological characteristics of optical coherence tomography defined plaque fissure in patients with acute coronary syndrome

      We assessed the plaque disruption in 245 consecutive patients with acute coronary syndrome undergoing percutaneous coronary intervention. The plaque fissure was diagnosed with optical coherence tomography, and intravascular ultrasound was used to determine arterial remodeling. Of them, 26 fissures were found in this study. The definite fissure was seen in 17 (65.4%) and probable fissure was seen in 9 (34.6%) patients. In 18 (69.2%), plaque fissure component was lipidic or thin-capped fibroatheroma. Eighteen (69.2%) of fissured plaque were seen within 30 mm of coronary ostium. Combined plaque fissure with plaque rupture/erosion was seen in 21 ...

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    11. Three dimensional neuro-retinal rim thickness and retinal nerve fiber layer thickness using high-definition optical coherence tomography for open-angle glaucoma

      Three dimensional neuro-retinal rim thickness and retinal nerve fiber layer thickness using high-definition optical coherence tomography for open-angle glaucoma

      Purpose To compare the diagnostic capability of three-dimensional (3D) neuro-retinal rim thickness (NRR) with existing optic nerve head and retinal nerve fiber layer (RNFL) scan parameters using high-definition optical coherence tomography (HD-OCT). Design Retrospective study. Methods Based on the mean deviation (MD) of the Humphrey Field Analyzer (HFA), the 152 subjects were categorized into mild (MD > − 6 dB, 100), moderate (MD − 6 to − 12 dB, 26), and severe (MD < − 12 dB, 26) glaucoma. The HD-OCT values of NRR, RNFL and ganglion cell inner plexiform layer (GCIPL) thicknesses, along with those of other parameters (rim area, disc area) were obtained, and ...

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    12. Retinal pigment epithelium hyperplasia overlying pigment epithelial detachment in age-related macular degeneration can masquerade as neovascularization on optical coherence tomography angiography

      Retinal pigment epithelium hyperplasia overlying pigment epithelial detachment in age-related macular degeneration can masquerade as neovascularization on optical coherence tomography angiography

      Purpose To report the image artifacts due to retinal pigment epithelium (RPE) hyperplasia overlying retinal pigment epithelial detachment (PED) in age-related macular degeneration (AMD), which can masquerade as neovascularization on optical coherence tomography angiography (OCTA). Methods A hospital-based, retrospective, and cross-sectional study. Twenty-two eyes from 16 patients with non-vascularized PED related to AMD were included in this study. All patients were examined by OCTA, spectral-domain optical coherence tomography, fluorescence angiography, and indocyanine green angiography. Vascular flow signals (VFS) on both the outer retinal slab of en face OCTA and cross-sectional OCTA and their correspondence with RPE hyperplasia were evaluated. Results ...

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    13. Measurement and Compensation for the Amplitude and Phase Spectral Distortions of an Interference Signal in Optical Coherence Tomography for the Relative Optical-Spectrum Width Exceeding 10%

      Measurement and Compensation for the Amplitude and Phase Spectral Distortions of an Interference Signal in Optical Coherence Tomography for the Relative Optical-Spectrum Width Exceeding 10%

      We describe a universal method of compensating for the arbitrary dispersion in the spectral and time domain optical coherence tomography systems. In combination with the amplitude method of correcting the optical-spectrum irregularities, this approach allows one to obtain the spectrally determined resolution if the instrument function is close to the Gaussian one. The efficiency of the method is demonstrated in the time and spectral domain optical coherence tomographies with the fully fiber-type optical systems for the relative optical-spectrum width exceeding 10%.

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    14. Optical Coherence Tomography in Glaucoma: A Practical Guide (Textbook)

      Optical Coherence Tomography in Glaucoma: A Practical Guide (Textbook)

      This book focuses on the practical aspects of Optical Coherence Tomography (OCT) in glaucoma diagnostics offering important theoretical information along with many original cases. OCT is a non-invasive imaging technique that acquires high-resolution images of the ocular structures. It enables clinicians to detect glaucoma in the early stages and efficiently monitor the disease. Optical Coherence Tomography in Glaucoma features updated information on technical applications of OCT in glaucoma, reviews recently published literature and provides clinical cases based on Cirrus and Spectralis OCT platforms. In addition, newer techniques like event and trend analyses for progression, macular ganglion cell analysis, and OCT ...

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      Mentions: UCLA
    15. Relationship between filtering bleb vascularization and surgical outcomes after trabeculectomy: an optical coherence tomography angiography study

      Relationship between filtering bleb vascularization and surgical outcomes after trabeculectomy: an optical coherence tomography angiography study

      Purpose To explore the relationship between the bleb vasculature and surgical outcome after trabeculectomy (TRAB) using optical coherence tomography angiography (OCT-A). Methods A prospective study was conducted, which included 26 eyes of 26 primary glaucoma patients in the final analysis. Thereinto, six patients underwent TRAB combined 5-FU and 12 patients received subconjunctival 5-FU injection postoperation. The bleb vessel was evaluated using OCT-A 1 week, 2 weeks, 1 month, 3 months, and 6 months after TRAB. Intraocular pressure (IOP), filtering bleb height, and bleb wall thickness were recorded at the same time. Pearson’s correlation analysis and linear regression analysis were ...

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    16. Improved analysis of foveal avascular zone area with optical coherence tomography angiography

      Improved analysis of foveal avascular zone area with optical coherence tomography angiography

      Purpose To investigate the relationship between the foveal avascular zone (FAZ) and the inner nuclear layer (INL)-free zone in the center of the fovea in order to provide an improved approach to evaluation of the FAZ area with optical coherence tomography angiography (OCTA). Methods Thirty-six healthy individuals (36 eyes) and 15 age-matched patients (15 eyes) with nonproliferative diabetic retinopathy (nPDR) were included in this study. The FAZ, as well as INL-free zone, was measured on OCTA images. The FAZ area, INL-free zone area, and the ratio of the INL-free zone area to the FAZ area were compared between healthy ...

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    17. Optical coherence tomography angiography assessment of the macular capillary plexus after surgery for macula-off rhegmatogenous retinal detachment

      Optical coherence tomography angiography assessment of the macular capillary plexus after surgery for macula-off rhegmatogenous retinal detachment

      Dear Editor, Macula-involved rhegmatogenous retinal detachment (RRD) is a condition that can cause severe central visual disturbance, even after successful retinal re-attachment. Optical coherence tomography angiography (OCTA) can measure vessel density (VD) in the macular capillary plexus (MCP), both superficially (the SCP) and deeply (the DCP), and can measure the foveal avascular zone (FAZ) in these layers. Previous research used OCTA to evaluate the correlation between the FAZ and visual acuity (VA) in the eyes with macula-off RRD [ 1 ]. Here, we extend previous results by including measurements of OCTA-measured VD in both the SCP and DCP, and compared these measurements ...

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    18. Microbubble contrast enhancement of neointima after drug-eluting stent implantation: an optical coherence tomography study

      Microbubble contrast enhancement of neointima after drug-eluting stent implantation: an optical coherence tomography study

      Microvessels within neoatherosclerosis are associated with vulnerability and increase from the early to the very late phase after drug-eluting stent implantation. Microbubble contrast agents have been suggested to enhance tissue microvasculature for optical coherence tomography (OCT) imaging. The present study investigated whether OCT signal intensity of neointima within stented segments was enhanced after intracoronary administration of microbubble contrast agents. A total of 40 patients who underwent follow-up coronary angiography after drug-eluting stent implantation were enrolled. At the time of follow-up coronary angiography, OCT images of the stented segments were recorded before and after intracoronary administration of microbubble contrast agents. Mean ...

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      Mentions: Kenichi Fujii
    19. Retinal flow density by optical coherence tomography angiography is useful for detection of nonperfused areas in diabetic retinopathy

      Retinal flow density by optical coherence tomography angiography is useful for detection of nonperfused areas in diabetic retinopathy

      Purpose Fluorescein angiography (FA) has been conventionally used for detection of retinal nonperfused area (NPA) in diabetic retinopathy (DR) in spite of its qualitative evaluation. Optical coherence tomography angiography (OCTA) has been recently reported to be useful for the quantification of retinal vascular disorder in DR. In this study, we examined whether retinal flow density (FD) measurement in OCTA was useful for NPA detection in DR. Methods The study included 41 eyes from 29 patients with DR who underwent FA and OCTA. Regions surrounded by arteries or veins were extracted in the OCTA image, and the FDs in each region ...

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    20. An investigation on optic nerve head involvement in Fuchs uveitis syndrome using optical coherence tomography and fluorescein angiography

      An investigation on optic nerve head involvement in Fuchs uveitis syndrome using optical coherence tomography and fluorescein angiography

      Purpose To investigate optic nerve head involvement in patients with Fuchs uveitis syndrome (FUS). Methods Optic nerve head of 43 FUS eyes without clinical optic disc edema and 37 unaffected fellow eyes were evaluated using optical coherence tomography (OCT) of peripapillary retina and retinal nerve fiber layer (RNFL) and fundus fluorescein angiography. Results Seventy-one percent of FUS eyes showed optic nerve head hyperfluorescence. The mean average RNFL thickness in FUS eyes was 115.0 ± 11.9 μm, which was thicker than unaffected eyes (103.0 ± 10.7 μm, p  < 0.001). Mean average of peripapillary retinal thicknesses in FUS eyes ...

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    21. Observation of anterior chamber volume after cataract surgery with swept-source optical coherence tomography

      Observation of anterior chamber volume after cataract surgery with swept-source optical coherence tomography

      Purpose To investigate the changes in the anterior chamber volume (ACV) with swept-source optical coherence tomography (SS-OCT) after cataract surgery and the factors that influence these ACV changes. Methods This was a prospective cohort study. Fifty-one patients who underwent cataract surgery were enrolled. Their ACV, anterior chamber depth, and angle widths were measured with SS-OCT before and 1 day, 1 week, and 1 month after surgery. The associations between the changes in ACV and posterior vitreous detachment (PVD) and axial length (AXL) were determined. Results Compared with the preoperative volume, ACV increased significantly at all three time points after surgery ...

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    22. Optical coherence tomography findings of falciform retinal detachment complicated with persistent fetal vasculature

      Optical coherence tomography findings of falciform retinal detachment complicated with persistent fetal vasculature

      Background Falciform retinal detachment (FRD) usually causes pronounced retinal wrinkles, and the prognosis of visual function is poor. In this present study, we report a rare case of FRD in which optical coherence tomography (OCT) findings revealed a relatively good visual function. Case presentation This study involved a 22-year-old female who had previously been diagnosed with FRD at 2 years of age, and who presented with microphthalmus in both eyes with pronounced retinal folds from the optic disc to the inferior-temporal side. Based on the clinical findings, we diagnosed it as persistent fetal vasculature (PFV). We found the visual function ...

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    23. The impact of tissue characterization for in-stent restenosis with optical coherence tomography during excimer laser coronary angioplasty

      The impact of tissue characterization for in-stent restenosis with optical coherence tomography during excimer laser coronary angioplasty

      We aimed to evaluate the impact of tissue characterization for in-stent restenosis (ISR) with optical computed tomography (OCT) during excimer laser coronary angioplasty (ELCA) in the drug-eluting stent (DES) era. The effect of ELCA for ISR according to differences in tissue characteristics is unclear. Fifty-three ISR lesions (7 bare metal stents and 46 drug-eluting stents) were treated with an ELCA catheter. After ELCA, balloon dilatation with either the scoring or non-compliant balloons was conducted. The procedure was completed by applying a drug-coated balloon. Tissue characterization and lumen measurement with OCT were performed thrice: (1) before percutaneous coronary intervention (PCI), (2 ...

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    1-24 of 660 1 2 3 4 ... 26 27 28 »
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