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    1. The fundus photo has met its match: optical coherence tomography and adaptive optics ophthalmoscopy are here to stay

      The fundus photo has met its match: optical coherence tomography and adaptive optics ophthalmoscopy are here to stay

      Purpose Over the past 25 years, optical coherence tomography (OCT) and adaptive optics (AO) ophthalmoscopy have revolutionised our ability to non-invasively observe the living retina. The purpose of this review is to highlight the techniques and human clinical applications of recent advances in OCT and adaptive optics scanning laser/light ophthalmoscopy (AOSLO) ophthalmic imaging. Recent findings Optical coherence tomography retinal and optic nerve head (ONH) imaging technology allows high resolution in the axial direction resulting in cross-sectional visualisation of retinal and ONH lamination. Complementary AO ophthalmoscopy gives high resolution in the transverse direction resulting in en face visualisation of retinal ...

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    2. The short-term effects of aflibercept on the size of choroidal neovascularization lesion in treatment-resistant neovascular age-related macular degeneration as determined by spectral-domain optical coherence tomography

      The short-term effects of aflibercept on the size of choroidal neovascularization lesion in treatment-resistant neovascular age-related macular degeneration as determined by spectral-domain optical coherence tomography

      Background and Objectives To evaluate the changes in the size of choroidal neovascularization (CNV) lesion using spectral domain-optical coherence tomography (SD-OCT) in patients with treatment-resistant neovascular age-related macular degeneration (AMD) who were switched from ranibizumab to aflibercept. Materials and Methods In this prospective case-series, 33 eyes of 30 patients with treatment-resistant neovascular AMD were included. Treatment-resistant neovascular AMD was defined as choriodal neovascularization secondary to AMD determined by subretinal fluid and/or intraretinal fluid/cysts after more than 6 months of monthly ranibizumab therapy. Enrolled eyes were received intravitreal aflibercept injections at weeks 0, 4, and 8. Maximum area of ...

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    3. In vivo optical imaging of amblyopia: Digital subtraction autofluorescence and split-spectrum amplitude-decorrelation angiography

      In vivo optical imaging of amblyopia: Digital subtraction autofluorescence and split-spectrum amplitude-decorrelation angiography

      Background and Objectives Amblyopia is a visual impairment that is attributed to either abnormal binocular interactions or visual deprivation. The retina and choroids have been shown to be involved in the development of amblyopia. The purpose of this study was to investigate the retinal and choroidal microstructural abnormalities of amblyopia using digital subtraction autofluorescence and split-spectrum amplitude-decorrelation angiography (SSADA) approaches. Methods This prospective study included 44 eyes of 22 patients with unilateral amblyopia. All patients who received indirect ophthalmoscopy, combined depth imaging spectral domain optical coherence tomography (OCT), SSADA-OCT, and macular blue light (BL-) and near-infrared (NIR-) autofluorescences underwent pupil ...

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    4. Validation of a diagnostic algorithm for the discrimination of actinic keratosis from normal skin and squamous cell carcinoma by means of high-definition optical coherence tomography

      Validation of a diagnostic algorithm for the discrimination of actinic keratosis from normal skin and squamous cell carcinoma by means of high-definition optical coherence tomography

      Introduction Actinic keratoses (AKs) commonly arise on sun-damaged skin. Visible lesions are often associated with subclinical lesions on surrounding skin, giving rise to field cancerization. To avoid multiple biopsies to diagnose subclinical/early invasive lesions, there is an increasing interest in non-invasive diagnostic tools, such as high-definition optical coherence tomography (HD-OCT). We previously developed a HD-OCT based diagnostic algorithm for the discrimination of AK from squamous cell carcinoma (SCC) and normal skin. The aim of this study was to test the applicability of HD-OCT for non-invasive discrimination of AK from SCC and normal skin using this algorithm. Methods Three-dimensional (3D ...

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    5. Activity assessment of root caries lesions with thermal and near-IR imaging methods

      Activity assessment of root caries lesions with thermal and near-IR imaging methods

      The purpose of this study was to evaluate thermal and near-infrared (NIR) reflectance imaging methods for the assessment of the activity of root caries lesions. In addition, changes in the lesion structure were monitored with polarization sensitive optical coherence tomography (PS-OCT). Artificial bovine and natural root caries lesions were imaged with PS-OCT, and their dehydration rate was measured with thermal and NIR cameras. The lesion activity of the natural root caries samples was also assessed by two clinicians by conventional means according to ICDAS II guidelines. The thickness of the highly mineralized transparent surface layer measured using PS-OCT increased and ...

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    6. Plaque morphology predictors of side branch occlusion after provisional stenting in coronary bifurcation lesion: Results of optical coherence tomography bifurcation study (ORBID)

      Plaque morphology predictors of side branch occlusion after provisional stenting in coronary bifurcation lesion: Results of optical coherence tomography bifurcation study (ORBID)

      Objectives The aim of this study was to identify the predictors of side branch (SB) ostial stenosis developed after provisional stenting of the main vessel (MV) using optical coherence tomography (OCT). Background Provisional stenting remains the main approach to treatment of bifurcation lesions; however, it may result in the narrowing of SB ostium. There is little information about underlying plaque morphology of the MV lesion and its potential impact on the SB after provisional stenting. Methods Patients with stable coronary disease with angiographic MV lesion not involving SB were included in a prospective single center study. The primary outcome was ...

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    7. Non-invasive assessment of corneal and conjunctival deterioration in soft contact lens users using anterior segment optical coherence tomography

      Non-invasive assessment of corneal and conjunctival deterioration in soft contact lens users using anterior segment optical coherence tomography

      Background The aim was to evaluate the corneal and bulbar conjunctival thicknesses of soft contact lens (SCL) wearers using anterior segment optical coherence tomography (AS-OCT). Methods The epithelial and overall thicknesses of both the central cornea and the infero-temporal bulbar conjunctiva of SCL wearers (30 subjects) were obtained by Cirrus HD-OCT and compared with those of refraction-matched controls (30 subjects) and patients with emmetropia (30 subjects). Results The mean corneal epithelial thicknesses in SCL wearing, spectacle-wearing and emmetropic groups were 48.97 ± 5.45, 52.18 ± 4.84 and 53.18 ± 5.05 µm, respectively. The corneal epithelium of members ...

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    8. Non-invasive optical assessment of viscosity of middle ear effusions in otitis media

      Non-invasive optical assessment of viscosity of middle ear effusions in otitis media

      In vivo Optical Coherence Tomography (OCT) image of a human tympanic membrane and Middle Ear Effusion (MEE) (top), with a CCD image of the tympanic membrane surface (inset). Below is the corresponding time-lapse M-mode OCT data acquired along the white dotted line over time, which can be analyzed to determine the Stokes–Einstein diffusion coefficient of the effusion. Eustachian tube dysfunction can cause fluid to collect within the middle ear cavity and form a middle ear effusion (MEE). MEEs can persist for weeks or months and cause hearing loss as well as speech and learning delays in young children. The ...

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    9. Spectral-Domain Optical Coherence Tomography as a Potential Biomarker in Huntington's Disease

      Spectral-Domain Optical Coherence Tomography as a Potential Biomarker in Huntington's Disease

      Background Spectral-domain optical coherence tomography has been used in several neurological conditions, and peripapillary and macular measurements have been proposed as potential biomarkers in these disorders. The aim of this study was to investigate retinal and choroidal changes in Huntington's disease and to evaluate any potential correlation with the stage of the disease. Methods A cross-sectional observational study compared patients with Huntington's disease and controls. Patients were evaluated using the Unified Huntington's Disease Rating Scale. Spectral-domain optical coherence tomography with enhanced depth imaging was used, and peripapillary choroidal and retinal nerve fiber layer thickness and macular retinal ...

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    10. Comparison of retinal nerve fiber layer and macular thickness for discriminating primary open-angle glaucoma and normal-tension glaucoma using optical coherence tomography

      Comparison of retinal nerve fiber layer and macular thickness for discriminating primary open-angle glaucoma and normal-tension glaucoma using optical coherence tomography

      Purpose The aim of this study was to evaluate the discrimination capabilities of macular and peripapillary retinal nerve fiber layer (pRNFL) thickness parameters as measured using spectral domain optical coherence tomography (SD-OCT) between primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG). Methods A total of 90 subjects were enrolled: 30 healthy subjects, 30 subjects with POAG and 30 subjects with NTG, consecutively. Retinal nerve fiber layer thickness, macular thickness and volume measurements were obtained with circular and radial SD-OCT scans. All parameters were compared between groups using an analysis of variance test. Areas under receiver-operating characteristic (AROC) curves with sensitivities ...

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    11. Four-dimensional live imaging of hemodynamics in mammalian embryonic heart with Doppler optical coherence tomography

      Four-dimensional live imaging of hemodynamics in mammalian embryonic heart with Doppler optical coherence tomography

      Four-dimensional live hemodynamic imaging of the mouse embryonic heart at embryonic day 9.0 using Doppler optical coherence tomography, showing directional blood flows in the sinus venosus, primitive atrium, atrioventricular region and vitelline vein. Hemodynamic analysis of the mouse embryonic heart is essential for understanding the functional aspects of early cardiogenesis and advancing the research in congenital heart defects. However, high-resolution imaging of cardiac hemodynamics in mammalian models remains challenging, primarily due to the dynamic nature and deep location of the embryonic heart. Here we report four-dimensional micro-scale imaging of blood flow in the early mouse embryonic heart, enabling time-resolved ...

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    12. Comparison of caries diagnostic modalities: A clinical study in 40 subjects

      Comparison of caries diagnostic modalities: A clinical study in 40 subjects

      Background and Objectives Few studies have been published that evaluate the usefulness of different caries- diagnostic modalities in general dental practice. The goal of this study was to compare the results of screening for coronal dental caries in a general dental practice using clinical observations, radiographs, laser fluorescence (DIAGNOdent™) (LF), and optical coherence tomography (OCT). Diagnostic agreement between OCT and LF versus standard clinical techniques for detecting caries was determined in 40 subjects. Study Designs/Materials and Methods Forty patients with >1 coronal carious lesion as determined by prescreening using clinical examination and radiographs were enrolled in this study. Subjects ...

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    13. Performance evaluation of automated segmentation software on optical coherence tomography volume data

      Performance evaluation of automated segmentation software on optical coherence tomography volume data

      Over the past two decades a significant number of OCT segmentation approaches have been proposed in the literature. Each methodology has been conceived for and/or evaluated using specific datasets that do not reflect the complexities of the majority of widely available retinal features observed in clinical settings. In addition, there does not exist an appropriate OCT dataset with ground truth that reflects the realities of everyday retinal features observed in clinical settings. While the need for unbiased performance evaluation of automated segmentation algorithms is obvious, the validation process of segmentation algorithms have been usually performed by comparing with manual ...

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    14. Pemphigus with features of both vulgaris and foliaceus variants localized to the nose

      Pemphigus with features of both vulgaris and foliaceus variants localized to the nose

      We report the case of a 74-year-old man affected by an unusual variant of pemphigus. He presented with a crusty and scaly lesion of the nose. We performed reflectance confocal microscopy and optical coherence tomography on the lesion, which suggested an unexpected diagnosis of pemphigus. Therefore, to confirm our diagnostic suspicions, we executed indirect immunofluorescence and two biopsies, one for histopathological examination and one for direct immunofluorescence. Histopathological evaluation showed acantholysis with formation of clefts in the granular and spinous layers of the epidermis. Direct immunofluorescence revealed immunoglobulin G and C3 deposit to the full thickness of the epidermis. Indirect ...

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    15. Clinical monitoring of smooth surface enamel lesions using CP-OCT during nonsurgical intervention

      Clinical monitoring of smooth surface enamel lesions using CP-OCT during nonsurgical intervention

      Introduction Studies have shown that cross-polarization optical coherence tomography (CP-OCT) can be used to image the internal structure of carious lesions in vivo . The objective of this study was to show that CP-OCT can be used to monitor changes in the internal structure of early active carious lesions on smooth surfaces during non-surgical intervention with fluoride. Methods Lesions on the smooth surfaces of teeth were imaged using CP-OCT on 17 test subjects. Lesion structural changes were monitored during fluoride varnish application at 6-week intervals for 30 weeks. The lesion depth ( L d ), integrated reflectivity (Δ R ), and surface zone thickness ( S ...

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    16. Usefulness of Frequency Domain Optical Coherence Tomography Compared with Intravascular Ultrasound as a Guidance for Percutaneous Coronary Intervention

      Usefulness of Frequency Domain Optical Coherence Tomography Compared with Intravascular Ultrasound as a Guidance for Percutaneous Coronary Intervention

      Objectives To compare outcomes and rates of optimal stent placement between optical coherence tomography (OCT) and intravascular ultrasound (IVUS) guided percutaneous coronary intervention (PCI). Background Unlike IVUS-guided PCI, rates of clinical outcomes and optimal stent placement have not been well characterized for OCT-guided PCI. Methods The study enrolled 290 patients who underwent implantation of a second generation drug eluting stent under OCT (122 patients) or IVUS (168 patients) guidance. The two groups were compared after adjusting for baseline differences using 1:1 propensity score matching (PSM) (114 patients in each group). Optimal stent placement was defined as achieving an adequate ...

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    17. Error rate of automated choroidal segmentation using swept-source optical coherence tomography

      Error rate of automated choroidal segmentation using swept-source optical coherence tomography

      Purpose To investigate the error rate of automated choroidal segmentation and the effect of frame averaging on error rate. Methods A horizontal B scan at the fovea was performed in patients having various retinochoroidal disorders using swept-source optical coherence tomography (OCT) with frame-averaging technique. Scanned images were classified into four morphological groups: normal from fellow eyes (N F ), normal from pathologic eyes (N P ), retinal abnormality (R) and retinochoroidal abnormality (RC) group. Choroidal segmentation was automatically performed using built-in software of a swept-source OCT device, and the error rate of choroidal segmentation was analysed. Results Qualified images for all four ...

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    18. In vivo, micro-morphological vascular changes induced by topical brimonidine studied by Dynamic optical coherence tomography

      In vivo, micro-morphological vascular changes induced by topical brimonidine studied by Dynamic optical coherence tomography

      Background Brimonidine is a selective α2 adrenergic receptor agonist with potent vasoconstrictive activity topically used for treatment of facial flushing and erythema caused by rosacea. Direct evidence for the in vivo morphology changes in skin vessels induced by topical application of brimonidine is limited. Dynamic optical coherence tomography is a novel technology that combines conventional OCT with information on flow and thereby provides supplementary information about the microvasculature. Dynamic OCT is non-invasive and creates high-resolution in vivo images of skin to a depth of maximum 2 mm. Objective The objective of this study was to examine and describe micro-morphological skin ...

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    19. Optical coherence tomography of actinic keratoses and basal cell carcinomas – differentiation by quantification of signal intensity and layer thickness

      Optical coherence tomography of actinic keratoses and basal cell carcinomas – differentiation by quantification of signal intensity and layer thickness

      Background Previous studies have shown that actinic keratoses (AKs) and basal cell carcinomas (BCCs) can be diagnosed by optical coherence tomography (OCT) based on morphological characteristics. There is a lack of systematic studies that give standardized information on signal intensity and layer thickness of AKs and BCCs. Objective The aim of this study was to find out if AKs and BCCs can be objectively diagnosed through standardized measurement of signal intensity and layer thickness and to use OCT as a non-invasive objective method for the diagnosis and evaluation of AKs and BCCs. Additionally, tumour and skin layer thickness were investigated ...

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    20. Optical Coherence Tomography as a Tool for Real-Time Visual Feedback and Biomechanical Assessment of Dermal Filler Injections: Preliminary Results in a Pig Skin Model

      Optical Coherence Tomography as a Tool for Real-Time Visual Feedback and Biomechanical Assessment of Dermal Filler Injections: Preliminary Results in a Pig Skin Model

      Dermal fillers are a popular anti-aging treatment with over 2 million procedures performed in the USA in 2013, and this figure will only increase as the aging population grows. Most FDA approved fillers last 3 to 24 months, depending on composition and injection site. There are numerous FDA-approved dermal fillers of varying compositions, with the most common being hyaluronic acid. Various fillers have optimal uses in specific skin layers corresponding to different degrees of treatment (1). Adverse reactions to dermal fillers are infrequent, and most are mild and superficial with no permanent effects (2).

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    21. A Comparison of Intravascular Imaging Modalities for Detection of Stent Struts in Acute Coronary Syndrome

      A Comparison of Intravascular Imaging Modalities for Detection of Stent Struts in Acute Coronary Syndrome

      Background We used optical coherence tomography (OCT) and intravascular ultrasound (IVUS) to assess the struts of implanted stents in patients with acute coronary syndrome (ACS). Methods A totle of 10,756 stent struts were analyzed with OCT in 42 patients of ACS. Of them, both of IVUS and OCT imaging were performed in 33 patients. Appearance of stent struts was classified as well apposed, buried, malapposed, and nondetectable, and the number of stent struts were counted by OCT and IVUS was compared. Results Most of stent struts were well apposed (78.1%, 8,407/10,756). However, malapposed struts were ...

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