1. 1-24 of 352 1 2 3 4 ... 13 14 15 »
    1. A method for monitoring enamel erosion using laser irradiated surfaces and optical coherence tomography

      A method for monitoring enamel erosion using laser irradiated surfaces and optical coherence tomography

      Introduction Since optical coherence tomography (OCT) is well suited for measuring small dimensional changes on tooth surfaces, OCT has great potential for monitoring tooth erosion. Previous studies have shown that enamel areas ablated by a carbon dioxide laser manifested lower rates of erosion compared to the non-ablated areas. The purpose of this study was to develop a model to monitor erosion in vitro that could potentially be used in vivo . Methods Thirteen bovine enamel blocks were used in this in vitro study. Each 10 mm × 2 mm block was partitioned into five regions, the central region was unprotected, the adjacent ...

      Read Full Article
    2. Bivalirudin versus unfractionated heparin for residual thrombus burden: A frequency-domain optical coherence tomography study

      Bivalirudin versus unfractionated heparin for residual thrombus burden: A frequency-domain optical coherence tomography study

      Objectives: This study aimed to compare the effect of bivalirudin and unfractionated heparin (UFH) on residual thrombus burden assessed by frequency-domain optical coherence tomography (FD-OCT), and on angiographic indices of microvascular obstruction (MVO). Background: The efficacy of bivalirudin to inhibit thrombus formation inside the stent during percutaneous coronary interventions (PCI) as compared to UFH is unknown. Methods: Sixty patients with coronary artery disease who underwent post-PCI FD-OCT were studied, including 20 patients treated with bivalirudin and 40 control patients treated with UFH, matched by clinical presentation, stent characteristics, and periprocedural medications. In-stent thrombus volume, thrombus score (number of quadrants with ...

      Read Full Article
    3. Retinal nerve fibre layer thickness measurements by optical coherence tomography in patients with sleep apnoea syndrome

      Retinal nerve fibre layer thickness measurements by optical coherence tomography in patients with sleep apnoea syndrome

      Background The study aims to investigate whether retinal nerve fibre layer (RNFL) abnormalities can be detected in patients with obstructive sleep apnoea/hypopnoea syndrome with normally appearing optic disc. Design This is an observational case-control study. Participants One hundred and eight consecutive patients with moderate or severe obstructive sleep apnoea/hypopnoea syndrome (OSAHS) as determined by overnight polysomnography and normal looking discs and 108 age-matched healthy controls were included in the study. Methods All patients underwent RNFL examinations by optical coherence tomography using fast retinal nerve fibre layer thickness scan. Main Outcome Measures The main outcome measure was RNFL thickness ...

      Read Full Article
    4. Novel endoscopic diagnosis for bladder cancer

      Novel endoscopic diagnosis for bladder cancer

      A dvances in endoscopic imaging technology may improve sensitivity for the detection of bladder cancer and provide a more complete understanding of the urothelial landscape, and it also may lead to improved short-term and long-term cancer control. Fluorescence cystoscopy requires intravesical administration of a photosensitizing agent (5-aminolevulinic acid or hexaminolevulinate), and imaging with a blue-light endoscopy system demonstrably improves the detection of papillary and flat bladder lesions compared with conventional white-light cystoscopy. Prospective phase 3 clinical trials have demonstrated improved diagnostic ability, enhanced tumor resection, and a small but significant reduction in recurrence-free survival. Optical coherence tomography delineates subsurface microarchitecture ...

      Read Full Article
    5. Optical coherence tomography in patients with a history of juvenile multiple sclerosis reveals early retinal damage

      Optical coherence tomography in patients with a history of juvenile multiple sclerosis reveals early retinal damage

      Background and purpose Some 3%−10% of patients with multiple sclerosis (MS) experience disease onset before the age of 18 years (‘early’ onset MS, EOMS). Optical coherence tomography is a non-invasive method to measure retinal nerve fibre layer thickness (RNFLT) and total macular volume (TMV) and may be useful to differentiate axonal and neuronal damage in the retina of patients with a history of EOMS. Here RNFLT and TMV in EOMS patients after a mean disease duration of 11.6 years were compared with patients with age- or disease-duration-matched later onset MS (LOMS) and healthy controls (HCs). Methods In this ...

      Read Full Article
    6. The ISNT rule in glaucoma: revisiting with spectral domain optical coherence tomography

      The ISNT rule in glaucoma: revisiting with spectral domain optical coherence tomography

      Purpose To evaluate the ability of the neuroretinal rim (NRR) rules determined using spectral domain optical coherence tomography (SDOCT) in diagnosing glaucoma and to study the effect of optic disc size and disease severity on the diagnostic ability of these rules. Methods In a cross-sectional study, 125 eyes of 96 glaucoma patients and 96 eyes of 72 control subjects underwent optic nerve head (ONH) imaging with SDOCT. Inferior (I), superior (S), nasal (N) and temporal (T) NRR areas were automatically determined by the sdoct software. Diagnostic abilities of ISNT (I > S > N > T), IT (I > T) and ST (S > T ...

      Read Full Article
    7. Treatment monitoring of topical ingenol mebutate in actinic keratoses with the combination of optical coherence tomography and reflectance confocal microscopy: a case series

      Treatment monitoring of topical ingenol mebutate in actinic keratoses with the combination of optical coherence tomography and reflectance confocal microscopy: a case series

      ingenol mebutate gel has been approved lately for the topical treatment of actinic keratoses (AK). Modern imaging techniques such as optical coherence tomography (OCT) and reflectance confocal microscopy (RCM) have been shown useful for the non-invasive diagnostics of non-melanoma skin cancer 1-6 . Both techniques differ in optical resolution and penetration depth.

      Read Full Article
      Mentions: Tanja Maier
    8. A multicentre pilot study investigating high-definition optical coherence tomography in the differentiation of cutaneous melanoma and melanocytic naevi

      A multicentre pilot study investigating high-definition optical coherence tomography in the differentiation of cutaneous melanoma and melanocytic naevi

      Background High-definition optical coherence tomography scanners have recently been developed. Objectives To assess the diagnostic performance of HD-OCT in the differentiation of benign melanocytic skin lesions (MSL) and cutaneous melanoma (CM). Methods Patients with MSL were assessed by HD-OCT. All diagnoses were histopathologically confirmed. One blinded observer evaluated both slice and en-face HD-OCT images and diagnosed MLS on the basis of an algorithm adopted from reflectance confocal microscopy, recent HD-OCT reports, and conventional OCT. Results A total of 93 MSL were studied comprising 66 benign MSL and 27 CM. The sensitivity of HD-OCT was 74.1% [95% confidence interval (CI ...

      Read Full Article
    9. Retinal Pathology detected by optical coherence tomography in an animal model of Parkinson's disease - Schneider - 2014 - Movement Disorders - Wiley Online Library

      Retinal Pathology detected by optical coherence tomography in an animal model of Parkinson's disease - Schneider - 2014 - Movement Disorders - Wiley Online Library

      Background Optical coherence tomography (OCT) is a noninvasive procedure for analysis of retinal morphology. Significant changes in the thickness of the peripapillary retinal nerve fiber layer (RNFL) in Parkinson's disease (PD) have been reported, and the current study was performed to examine whether such changes can also be detected in an animal model of PD. Methods Optical coherence tomography measurements of peripapillary RNFL thickness, macula volume, and foveal thickness were obtained from 10 normal and five 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated cynomolgus monkeys with stable Parkinsonian signs. Results Average RNFL thickness was significantly decreased in Parkinsonian monkeys compared ...

      Read Full Article
    10. Optical coherence tomography applied to tests of skin care products in humans – a case study

      Optical coherence tomography applied to tests of skin care products in humans – a case study

      Background/purpose When evaluating skin care products for human skin, quantitative test methods need to be simple, precise and reliable. Optical coherence tomography (OCT), provides high-resolution sectional images of translucent materials to a depth of a few millimeters, a technique usually applied to medical measurements in ophthalmology and dermatology. This study aimed to demonstrate the application of OCT as the main technique for monitoring changes in skin topography during tests of a wrinkle-reduction product in humans. Methods We used a commercial OCT apparatus to perform clinical examinations of skin roughness in treated and non-treated sites in the periorbital region of ...

      Read Full Article
      Mentions: Marcus P. Raele
    11. Real-time three-dimensional imaging of epidermal splitting and removal by high-definition optical coherence tomography

      Real-time three-dimensional imaging of epidermal splitting and removal by high-definition optical coherence tomography

      Background While real-time 3-D evaluation of human skin constructs is needed, only 2-D non-invasive imaging techniques are available. Objective Evaluation of the potential of High-Definition Optical Coherence Tomography (HD-OCT) for real-time 3-D assessment of the epidermal splitting and de-cellularisation. Methods Human skin samples were incubated with four different agents: Dispase II, NaCl 1M, Sodium Dodecyl Sulfate (SDS) and Triton X-100. Epidermal splitting, dermo-epidermal junction, acellularity and 3-D architecture of dermal matrices were evaluated by High-Definition Optical Coherence Tomography before and after incubation. Real-time 3-D HD-OCT assessment was compared with 2-D en face assessment by Reflectance Confocal Microscopy (RCM). (Immuno)histopathology ...

      Read Full Article
    12. Comparison of scanning electron microscopy and optical coherence tomography (OCT) for imaging of coronary bifurcation stents

      Comparison of scanning electron microscopy and optical coherence tomography (OCT) for imaging of coronary bifurcation stents

      Background: Optical coherence tomography (OCT) is a new intracoronary imaging modality that has excellent resolution and image quality and has been used to image neointimal coverage after stent implantation. OCT has been compared to histologic, intravascular ultrasound, and scanning electron microscopy (SEM) studies. However, OCT has not been compared with SEM for imaging stent coverage over side branches. Objective: The aim of this study was to compare OCT with scanning electron microscopy (SEM) in imaging neointimal coverage over stent struts bridging coronary side-branch ostia. Methods: Using a balloon-overstretch in-stent restenosis model, we deployed 38 everolimus-eluting stents across coronary bifurcations in ...

      Read Full Article
    13. Diabetic macular oedema quantified with spectral-domain optical coherence tomography – evaluation of boundary line artefacts and the effect on retinal thickness

      Diabetic macular oedema quantified with spectral-domain optical coherence tomography – evaluation of boundary line artefacts and the effect on retinal thickness

      Purpose To characterize frequency, morphological cause and time-dependent change of boundary line artefacts in optical coherence tomography (OCT) examinations of centre-involved diabetic macular oedema (ciDME) patients who underwent ranibizumab treatment with 1-year follow-up and to evaluate the impact of artefacts on retinal thickness. Methods One hundred and fourteen patients were examined with radial scan protocol by Topcon 3D OCT at baseline, 3 and 12 months. All B scans from all visits were examined for boundary line artefacts (artefacts) and were stratified by morphological element causing artefacts including hard exudates (HE), epiretinal membranes (ERM), optical opacities and serous detachments. Boundary line ...

      Read Full Article
    14. Grader learning effect and reproducibility of Doppler Spectral‐Domain Optical Coherence Tomography derived retinal blood flow measurements

      Grader learning effect and reproducibility of Doppler Spectral‐Domain Optical Coherence Tomography derived retinal blood flow measurements

      Purpose To investigate grader learning effect and to quantify intergrader reproducibility of Doppler Spectral-Domain Optical Coherence Tomography (SD-OCT) derived retinal blood flow measurements. Methods Fifteen healthy young subjects (mean age 28.44; SD 3 years) underwent Doppler SD-OCT scans of one eye using the circumpapillary double circular scan protocol of the Optovue RTVue by one of two experienced operators. One trained (i.e. having undergone certification) and one novice (i.e. preliminary training comprising five standard practice data sets) individual then graded a standardized set of scans, consisting of 15 data sets (session 1) using custom Doppler Optical Coherence Tomography ...

      Read Full Article
    15. Evaluation of the chorioretinal thickness changes in Alzheimer's disease using spectral-domain optical coherence tomography

      Evaluation of the chorioretinal thickness changes in Alzheimer's disease using spectral-domain optical coherence tomography

      Background To assess the chorioretinal thickness changes using spectral-domain optical coherence tomography (SD-OCT) and to evaluate the association between these structural changes and cognitive impairment in Alzheimer's disease (AD). Design Prospective, cross-sectional study Participants 31 eyes of 31 consecutive patients with AD and 30 eyes of 30 cognitively healthy age-matched control subjects were recruited Methods SD-OCT (RTVue-100) was used to measure the macular ganglion cell complex thickness (mGCC), outer retinal thickness (ORL), and the choroidal thickness (CT). Cognitive function was evaluated by Mini-Mental State examination (MMSE) on the same day of the optical examination. Main Outcome Measures chorioretinal thickness ...

      Read Full Article
    16. Achromatopsia: case presentation and literature review emphasising the value of spectral domain optical coherence tomography

      Achromatopsia: case presentation and literature review emphasising the value of spectral domain optical coherence tomography

      A literature review and case presentation are used to discuss the diagnostic value of spectral domain optical coherence tomography (SD-OCT) in the assessment and management of congenital achromatopsia. A 24-year-old Hispanic man presented to the clinic with a longstanding history of decreased vision and associated possible recent progression. A comprehensive eye examination and a battery of tests including SD-OCT, fundus photography, electroretinogram (ERG) and Farnsworth D-15 were completed. SD-OCT and photopic ERG confirmed the clinical diagnosis of congenital achromatopsia. There was the classic subfoveal flattened hyporeflective ‘punched out’ zone, resulting from an absence of inner segment/outer segment junction. SD-OCT ...

      Read Full Article
    17. Morphometric grading of osteoarthritis by optical coherence tomography - An ex vivo study

      Morphometric grading of osteoarthritis by optical coherence tomography - An ex vivo study

      Optical Coherence Tomography (OCT) yields microscopic cross-sectional images of cartilage in real time and at high resolution. As yet, comprehensive grading of degenerative cartilage changes based on OCT has rarely been performed. This study investigated the potential of quantitative OCT using algorithm-based image parameters such as irregularity (OII – Optical Irregularity Index), homogeneity (OHI – Optical Homogeneity Index) and attenuation (OAI – Optical Attenuation Index) in the objective grading of cartilage degeneration. Therefore, OCT was used to image and assess 113 human osteochondral samples obtained from total knee replacements. Processing included the analysis of OII (by calculation of the standard deviation with regards ...

      Read Full Article
    18. Evaluation of the macular choroidal thickness using spectral optical coherence tomography in patients with obstructive sleep apnea syndrome

      Evaluation of the macular choroidal thickness using spectral optical coherence tomography in patients with obstructive sleep apnea syndrome

      Background To assess the choroidal thickness (CT) in patients with obstructive sleep apnea syndrome (OSAS) and healthy controls. Design Prospective, cross-sectional study Participants 92 eyes of 92 patients with OSAS and 32 eyes of 32 age- and body mass index-matched healthy subjects were enrolled. Methods OSAS patients were further divided into mild, moderate and severe OSAS groups according to their apnea hypopnea index (AHI) values. The macular CT and peripapillary retinal nerve fiber layer (RNFL) thickness measurements of the subjects were obtained using spectral domain optical coherence tomography (RTVue-100, Optovue). The CT and RNFL thickness measurements of the groups were ...

      Read Full Article
    19. Optical coherence tomography for the evaluation of asymmetric cardiac allograft vasculopathy in a child

      Optical coherence tomography for the evaluation of asymmetric cardiac allograft vasculopathy in a child

      We present an unusual case of CAV in a child with isolated disease in the LAD coronary artery. Initial progression of the disease appeared to have been halted by the use of sirolimus, but the assessment of disease in other vessels (particularly the RCA) was of particular importance in deciding whether or not to relist this patient for transplantation. Due to the known limitations of coronary angiography, we used OCT to assess for angiographically silent CAV. The normal intravascular appearance of the RCA by OCT was reassuring, and the child was not relisted for transplantation. OCT offers multiple advantages for ...

      Read Full Article
    20. Mechanism of luminal patency of the self-expanding sideguard sidebranch stent: Evaluation by intravascular ultrasound and optical coherence tomography

      Mechanism of luminal patency of the self-expanding sideguard sidebranch stent: Evaluation by intravascular ultrasound and optical coherence tomography

      Background : The Cappella Sideguard (CS) sidebranch stent is a self-expanding, thin-strut, nitinol device with anatomic flaring at the sidebranch ostium designed to treat bifurcation lesions. Objective : To evaluate the mechanism of long-term lumen patency of the novel, self-expanding CS sidebranch stent compared to a balloon-expandable stent in the main vessel. Methods : We performed intravascular ultrasound (IVUS) post-intervention and at follow-up in 24 CS stents and in 28 balloon-expandable drug-eluting stents deployed in the corresponding main vessel. Thirteen patients also had optical coherence tomography (OCT) at follow-up to evaluate neointimal hyperplasia and strut coverage. Results : CS stent area at the sidebranch ...

      Read Full Article
    21. Multimodality imaging of the effects of a novel dentifrice on oral biofilm

      Multimodality imaging of the effects of a novel dentifrice on oral biofilm

      Objective Oral biofilm formation and progression on the surface of the tooth can lead to advanced oral disease such as gingivitis. The purpose of this randomized, controlled, double-blinded study was to evaluate the effects of a novel dental gel on oral plaque biofilm using multimodal imaging techniques. Materials and Methods Twenty-five subjects with moderate gingival inflammation (Löe and Silness Gingival Index ≥2) and pocket depths <4 were randomly assigned to brush twice daily for 21 days with the test or the control dental gel. In vivo multimodality in situ imaging was performed over a 3-week period using in vivo ...

      Read Full Article
    22. Optical coherence tomography as a tool for characterization of complex biological surfaces

      Optical coherence tomography as a tool for characterization of complex biological surfaces

      The advent of scanning electron microscopy has facilitated our understanding of the biology in relation to surface microstructure of many invertebrates. In recent years, interest in biomimetics and bio-inspired materials has further propelled the search for novel microstructures from natural surfaces. As this search widens in diversity to nurture deeper understanding of form and function, the need often arises to examine rare specimens. Unfortunately, most methods for characterization of the microtopography of natural surfaces are sacrificial, and as such, place limiting constraints on research progress in situations where only a few rare specimens are known, such as the rich resources ...

      Read Full Article
    1-24 of 352 1 2 3 4 ... 13 14 15 »
  1. Categories

    1. Applications:

      Art, Cardiology, Dentistry, Dermatology, Developmental Biology, Gastroenterology, Gynecology, Microscopy, NDE/NDT, Neurology, Oncology, Ophthalmology, Other Non-Medical, Otolaryngology, Pulmonology, Urology
    2. Business News:

      Acquisition, Clinical Trials, Funding, Other Business News, Partnership, Patents
    3. Technology:

      Broadband Sources, Probes, Tunable Sources
    4. Miscellaneous:

      Jobs & Studentships, Student Theses, Textbooks