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    1. Assessment of early occlusal caries pre- and post- sealant application—An imaging approach

      Assessment of early occlusal caries pre- and post- sealant application—An imaging approach

      Background and Objective Clinicians have difficulty assessing and monitoring early occlusal caries. Traditional clinical exam and radiographs are unable to detect the subtle alterations in enamel indicative of de- or re-mineralization, particularly under dental sealants. Although clinicians have used laser fluorescence (LF) to address this gap, this modality has demonstrated weak correlation with histology. The International Caries Detection and Assessment System (ICDAS-II) has demonstrated high sensitivity and specificity for caries detection, but since it is based on visual assessment, it is of no use in areas beneath the most commonly used dental sealants which are opaque. Optical coherence tomography (OCT ...

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    2. Optic nerve head assesment: comparison of Cirrus optic coherence tomography and Heidelberg Retinal Tomograph 3

      Optic nerve head assesment: comparison of Cirrus optic coherence tomography and Heidelberg Retinal Tomograph 3

      Background The purpose of this study was to analyze the relationship between Optic Nerve Head (ONH) parameters measured by spectral domain optical coherence tomography and confocal scanning laser ophthalmoscope. Design Prospective, cross-sectional study. Hospital setting. Participants One hundred seventy-three subjects (85 glaucoma and 88 normal subjects). Methods One eye from each individual was selected randomly for ONH imaging by the spectral domain Cirrus OCT and Heidelberg Retinal Tomograph 3 (HRT3). Main Outcome Measures Four ONH parameters that are measured by both technologies (average cup to disc ratio (CDR), rim area, disc area and cup volume) were analyzed and compared for ...

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    3. Optical Coherence Tomography-Guided Retinal Prosthesis Design: Model of Degenerated Retinal Curvature and Thickness for Patient-Specific Devices

      Optical Coherence Tomography-Guided Retinal Prosthesis Design: Model of Degenerated Retinal Curvature and Thickness for Patient-Specific Devices

      Retinitis pigmentosa affects over 1.5 million people worldwide and is a leading cause of vision loss and blindness. While retinal prostheses have shown some success in restoring basic levels of vision, only generic, “one-size-fits-all” devices are currently being implanted. In this study, we used optical coherence tomography scans of the degenerated retina from 88 patients with retinitis pigmentosa to generate models of retinal thickness and curvature for the design of customized implants. We found the average retinal thickness at the fovea to be 152.9 ± 61.3 μm, increasing to a maximum retinal thickness of 250.9 ± 57.5 ...

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    4. Miniature forward-imaging B-scan optical coherence tomography probe to guide real-time laser ablation

      Miniature forward-imaging B-scan optical coherence tomography probe to guide real-time laser ablation

      Background and Objective Investigations have shown that pulsed lasers tuned to 6.1 µm in wavelength are capable of ablating ocular and neural tissue with minimal collateral damage. This study investigated whether a miniature B-scan forward-imaging optical coherence tomography (OCT) probe can be combined with the laser to provide real-time visual feedback during laser incisions. Study Design/Methods and Materials A miniature 25-gauge B-scan forward-imaging OCT probe was developed and combined with a 250 µm hollow-glass waveguide to permit delivery of 6.1 µm laser energy. A gelatin mixture and both porcine corneal and retinal tissues were simultaneously imaged and ...

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    5. Spectroscopic study on appearances of make-up skins using a visible RGB-LED OCT

      Spectroscopic study on appearances of make-up skins using a visible RGB-LED OCT

      Background/purpose Facial foundation is very effective to correct color irregularities of the skin surface and to protect the skin from harmful light. This depends strongly on both the optical properties and the coating condition of foundation on the skin surface. Methods We constructed the full-field optical coherence tomography (OCT) (FF-OCT) microscope with visible light sources of RGB LEDs. The commercially available skin replicas were used as the model of skin in the experiment, which were composed of two layers, a thin polyurethane film transcribed from cheek surface of a female and a beige-colored silicone substrate. The foundations were applied ...

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    6. Techniques and best practices for optical coherence tomography: A practical manual for interventional cardiologists

      Techniques and best practices for optical coherence tomography: A practical manual for interventional cardiologists

      Optical Coherence Tomography (OCT) is a novel intracoronary imaging modality that utilizes near-infrared light to provide information regarding lesion length and severity, vessel lumen diameter, plaque morphology, as well as the opportunity for stent procedure guidance and follow-up. While analogous to intravascular ultrasound (IVUS), the specific imaging properties, including significantly higher resolution, and technical specifications of OCT offer the ability for intracoronary diagnostic and interventional procedure guidance roles that require a thorough understanding of the technology. We provide coronary interventionalist's a user's guide to OCT, focusing on techniques and approaches to optimize imaging, with a focus on efficiency ...

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    7. Usefulness of optical coherence tomography to detect central serous chorioretinopathy in monkeys

      Usefulness of optical coherence tomography to detect central serous chorioretinopathy in monkeys

      Many systemic drugs can induce ocular toxicity and several ocular side-effects have been identified in clinical studies. However, it is difficult to detect ocular toxicity in preclinical studies because of the lack of appropriate evaluation methods. Optical coherence tomography (OCT) is useful because it can provide real-time images throughout a study period, whereas histopathology only provides images of sacrificed animals. Using OCT alongside histopathology, attempts were made to find effective approaches for screening of drug-induced ocular toxicity in monkeys. Such approaches could be used in preclinical studies prior to human trials. Six male cynomolgus monkeys ( Macaca fascicularis Raffles ) were orally ...

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    8. Optical coherence tomography using images of hair structure and dyes penetrating into the hair

      Optical coherence tomography using images of hair structure and dyes penetrating into the hair

      Background/purpose Hair dyes are commonly evaluated by the appearance of the hair after dyeing. However, this approach cannot simultaneously assess how deep the dye has penetrated into hair. Methods For simultaneous assessment of the appearance and the interior of hair, we developed a visible-range red, green, and blue (RGB) (three primary colors)-optical coherence tomography (OCT) using an RGB LED light source. We then evaluated a phantom model based on the assumption that the sample's absorbability in the vertical direction affects the tomographic imaging. Results Consistent with theory, our device showed higher resolution than conventional OCT with far-red ...

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    9. Hydrogel-Forming Microneedles Increase in Volume During Swelling in Skin, but Skin Barrier Function Recovery is Unaffected

      Hydrogel-Forming Microneedles Increase in Volume During Swelling in Skin, but Skin Barrier Function Recovery is Unaffected

      We describe, for the first time, quantification of in-skin swelling and fluid uptake by hydrogel-forming microneedle (MN) arrays and skin barrier recovery in human volunteers. Such MN arrays, prepared from aqueous blends of hydrolyzed poly(methylvinylether/maleic anhydride) (15%, w/w) and the cross-linker poly(ethyleneglycol) 10,000 Da (7.5%, w/w), were inserted into the skin of human volunteers ( n = 15) to depths of approximately 300 μm by gentle hand pressure. The MN arrays swelled in skin, taking up skin interstitial fluid, such that their mass had increased by approximately 30% after 6 h in skin. Importantly, however ...

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    10. Effect of high myopia on glaucoma diagnostic parameters measured with optical coherence tomography

      Effect of high myopia on glaucoma diagnostic parameters measured with optical coherence tomography

      Background We examined the influence of high myopia on conventional spectral-domain optical coherence tomographic parameters and assessed the macular ganglion cell complex thickness to macular outer retinal thickness ratio as a new optical coherence tomography parameter. Design Prospective cross-sectional study Participants Sixty normal and 30 highly myopic eyes (refractive error more than -6 D). Methods We used the RTVue-100 to measure macular ganglion cell complex and circumpapillary retinal nerve fibre layer thickness, global loss volume, and focal loss volume and then calculated the ganglion cell complex thickness to macular outer retinal thickness ratio. Main Outcome Measures Each parameter was compared ...

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    11. Better Inflation Time of Stent Balloon for Second-Generation Drug-Eluting Stent Expansion and Apposition: An Optical Coherence Tomography Study

      Better Inflation Time of Stent Balloon for Second-Generation Drug-Eluting Stent Expansion and Apposition: An Optical Coherence Tomography Study

      Objectives We tried to determine the effect of stent balloon inflation time on stent expansion and apposition using optical coherence tomography . Background Second-generation drug-eluting stents (DES) have thin struts; however, inflation times for optimal stent expansion and apposition are unknown in vivo . Methods Subjects included 17 patients (18 de novo coronary artery lesions), in whom Resolute Integrity → (n = 9) and Xience Prime → (n = 9) DES were deployed. All stents were inflated 3 times to the nominal inflation pressure (8.9 ± 0.6 atm) using the stent delivery balloon. The first inflation continued until the stent was angiographically fully expanded; the ...

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    12. High-definition optical coherence tomography and reflectance confocal microscopy in the in vivo visualization of a reaction to permanent make-up

      High-definition optical coherence tomography and reflectance confocal microscopy in the in vivo visualization of a reaction to permanent make-up

      Background and Objectives After permanent make-up treatments, eczematous and granulomatous reactions may occur which need anti-inflammatory treatment. For the definite diagnosis oftentimes biopsies are recommended. In vivo imaging such as reflectance confocal microscopy (RCM) and high-definition optical coherence tomography (HD-OCT) has been successfully used in the non-invasive diagnosis of various dermatoses before. Methods Here, we report on non-invasive imaging of a reaction towards permanent make-up in a 40-year-old woman by using HD-OCT and RCM. Results Both in HD-OCT and in RCM subepidermal pigment and granulomatous changes could be visualized and correlated with the histopathological findings. Regression of the lesions in ...

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      Mentions: AGFA Healthcare
    13. Optical coherence contrast imaging using gold nanorods in living mice eyes

      Optical coherence contrast imaging using gold nanorods in living mice eyes

      Background Optical Coherence Tomography (OCT) is a powerful imaging modality to visualize tissue structures, with axial image pixel resolution as high as 1.6 um in tissue. However, OCT is intrinsically limited to providing structural information as the OCT contrast is produced by optically scattering tissues. Methods Here we demonstrate gold nanorods (GNRs) injected into the anterior chamber (AC) and cornea of mice eyes can create a significant OCT signal and hence can be used as a contrast agent for in vivo OCT imaging. Results We show that a low dose of 30 nM of GNRs (13 nm in diameter ...

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    14. Correlation of optical coherence tomography and histology in microcystic adnexal carcinoma: a case report

      Correlation of optical coherence tomography and histology in microcystic adnexal carcinoma: a case report

      Background/Aims Herein, we report a case of microcystic adnexal carcinoma (MAC), which we correlated and evaluated by optical coherence tomography (OCT) and conventional H&E histology. Methods A commercially available OCT scanner was used for imaging. Several multi-slice images were obtained from the central portion of the lesion. Correlation of OCT findings with histology was performed retrospectively. Results Microcystic adnexal carcinoma showed characteristic criteria, which were divided into superficial and sub-epidermal findings. Conclusion The use of OCT can visualize characteristic criteria of MAC, thus enabling prompt diagnosis before surgery.

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    15. Myocardial Infarction Due to Intracoronary Embolization of Percutaneous Coronary Intervention Packaging

      Myocardial Infarction Due to Intracoronary Embolization of Percutaneous Coronary Intervention Packaging

      Intracoronary device loss is occasionally encountered and removal is commonly performed at the time of the procedure. We report a case of removal of a retained coronary balloon protective plastic tubing inadvertently left in the coronary artery for a month and associated with myocardial infarction. Optical coherence tomography was used to visualize the foreign body prior to removal with a snare. To our knowledge this is the first report of a removal of disposable packaging equipment after prolonged intracoronary dwell time.

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    16. Difference of neointimal growth patterns in bifurcation lesions among four kinds of drug-eluting stents: An optical coherence tomographic study

      Difference of neointimal growth patterns in bifurcation lesions among four kinds of drug-eluting stents: An optical coherence tomographic study

      Aim : Neointimal proliferation of bifurcation lesions after implantation of drug-eluting stents (DES) has not been well evaluated. Thus, we compared neointimal proliferation of bifurcation lesions among four DES using optical coherence tomography (OCT). Methods : Eight-month follow-up OCT was performed in 68 bifurcation lesions treated by 15 sirolimus-eluting stents (SES) and 17 paclitaxel-eluting stents (PES) as first-generation DES, and by 17 zotarolimus-eluting stents (ZES) and 19 everolimus-eluting stents (EES) as second-generation DES. Cross-sectional images of the bifurcation lesion using OCT were analyzed every 450 µm. All images were divided into three areas: inner wall of the bifurcation (IB), outer wall of ...

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    17. Evaluation of ultrasound and glucose synergy effect on the optical clearing and light penetration for human colon tissue using SD-OCT

      Evaluation of ultrasound and glucose synergy effect on the optical clearing and light penetration for human colon tissue using SD-OCT

      Topical application optical clearing agents (OCAs) can effectively enhance the tissue optical clearing on the human colon tissue, which has been demonstrated in our previous studies. Nevertheless, the strong light scattering still limits the diffusion rate of OCAs and penetration depth of light into the tissue. In this study, in order to further increase the diffusion of the OCA of glucose into tissue, we employ a method to improve the glucose permeability and light penetration with ultrasound (sonophoretic delivery, SP) and glucose (G) synergy on human normal and cancerous colon tissues in vitro, which was measured and quantified with spectral-domain ...

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    18. Imaging of Mohs Micrographic Surgery Sections Using Full-Field Optical Coherence Tomography: A Pilot Study

      Imaging of Mohs Micrographic Surgery Sections Using Full-Field Optical Coherence Tomography: A Pilot Study

      Background Full-field optical coherence tomography (FF-OCT) is a new noninvasive imaging technique that can see down to the cellular level without tissue preparation or contrast agents. Objective To use FF-OCT to image Mohs micrographic surgery specimens and verify the ability of a dermatopathologist to identify or exclude malignancy. Materials and Methods Two Mohs surgeons supplied 18 Mohs sections from 11 patients. Each section was scanned using the FF-OCT, and a dermatopathologist blinded to the diagnosis examined the images for malignancy. The FF-OCT images were then compared with the intraoperative hematoxylin and eosin (H&E)-stained frozen sections for concordance. Results ...

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    19. Serial optical coherence tomography images of trapped balloon catheter after bailout stenting

      Serial optical coherence tomography images of trapped balloon catheter after bailout stenting

      The increased use of endovascular interventions has resulted in a growing number of complications pertaining to unretrievable devices. We report a case of balloon dislodgement in a coronary artery during percutaneous coronary intervention (PCI) with bailout stenting used bare metal stent (BMS). We could not retrieve the remnant despite several attempts and techniques. Thereafter, we deployed BMS to bail out thrombus to recover the coronary flow. Emergency surgery was not considered because of high perioperative mortality (EuroSCORE II 55.91%). We did careful follow up with frequency domain optical coherence tomography (FD-OCT) images, which revealed thick neointima hyperplasia that completely ...

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    20. Histopathological correlates of basal cell carcinoma in slice and en-face imaging modes of high-definition optical coherence tomography

      Histopathological correlates of basal cell carcinoma in slice and en-face imaging modes of high-definition optical coherence tomography

      Background High-definition optical coherence tomography (HD-OCT) scanners have recently been developed providing significantly higher resolution than conventional OCT . Objectives To assess the relationship between recently defined histopathological HD-OCT correlates of basal cell carcinomas (BCC) and possible predictors for the most common tumour subtypes. Methods For HD-OCT imaging, we used the Skintell ® device (Agfa Healthcare, Mortsel, Belgium). Twenty-five BCCs were histopathologically (including vertical as well horizontal haematoxylin and eosin and Alcian blue sectioning) confirmed and correlated with HD-OCT images. Results In the en-face mode, lobulated nodules were seen in 21 of the 25 lesions (84%), peripheral rimming in 18 (25/72 ...

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