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    1. Non-invasive imaging of a choroidal macrovessel

      Non-invasive imaging of a choroidal macrovessel

      Purpose To describe novel anatomic findings of an apparent choroidal macrovessel, originally misdiagnosed as a choroidal tumor, using non-invasive imaging tools. Observations Initial ophthalmic examination revealed an elevated hypopigmented choroidal mass in the macular area, with a serpentine track extending temporally to the equator. Enhanced depth imaging optical coherence tomography (EDI-OCT) revealed an optically hollow lesion just outside the choroid-scleral junction (CSJ), indenting the retina and compressing the choroid from the scleral side. Optical coherence tomography angiography (OCTA) at the choroidal level showed relative low flow within the lesion. En face OCT at the level of the choroid demonstrated similar ...

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    2. Donor specific anti-HLA antibodies and cardiac allograft vasculopathy: A prospective study using highly automated 3-D optical coherence tomography analysis

      Donor specific anti-HLA antibodies and cardiac allograft vasculopathy: A prospective study using highly automated 3-D optical coherence tomography analysis

      Introduction Recent studies suggested potential positive correlations between HLA-specific antibodies and development of cardiac allograft vasculopathy (CAV). Methods This prospective two-center study investigated early progression of CAV by coronary optical coherence tomography in 1 month and 12 months after heart transplantation (HTx) in 104 patients. Detection and characterization of donor specific (DSA) and MHC class-I polypeptide-related sequence A (MICA) antibodies were performed before, 1, 6 and 12 months after transplantation. Results During the first post-HTx year, we observed a significant reduction in the mean coronary luminal area (P < .001), and progression in mean intimal thickness (IT) (P < .001). DSA and ...

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    3. Assessment of Retinal Vessel Density in Adult-Onset Foveomacular Vitelliform Dystrophy by Optical Coherence Tomography Angiography

      Assessment of Retinal Vessel Density in Adult-Onset Foveomacular Vitelliform Dystrophy by Optical Coherence Tomography Angiography

      Background To evaluate retinal thickness, area of foveal avascular zone (FAZ), flow area and flow density of choriocapillaris, vessel density of both superficial capillary plexus (SCP) and deep capillary plexus (DCP) of eyes with adult-onset foveomacular vitelliform dystrophy (AOFVD) using optical coherence tomography angiography (OCT-A) and compare the results with healthy controls. Methods 17 eyes of 14 patients diagnosed with AOFVD and 17 eyes of 17 healthy subjects were enrolled in this study. All patients underwent a complete ophthalmological examination and a 6 x 6 mm macular OCT-A scanning. Quantiative results of retinal thickness, retinal vessel density of SCP and ...

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    4. A feasibility study of the DyeVert™ plus contrast reduction system to reduce contrast media volumes in percutaneous coronary procedures using optical coherence tomography

      A feasibility study of the DyeVert™ plus contrast reduction system to reduce contrast media volumes in percutaneous coronary procedures using optical coherence tomography

      bjective To evaluate the feasibility of using the DyeVert™ Plus EZ Contrast Reduction System in optical coherence tomography (OCT)-guided percutaneous coronary intervention (PCI) procedures and to assess OCT image quality. Background OCT is employed as a powerful intravascular imaging modality; however, it requires blood displacement via contrast injection during image acquisition, thereby posing risk of nephrotoxicity. The DyeVert System is designed to reduce and facilitate monitoring of contrast media volume (CMV) delivered, without diminishing image quality. Methods We conducted a prospective clinical feasibility study to determine whether the DyeVert System is non-inferior to manual contrast injection in reducing CMV ...

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      Mentions: Hiram G. Bezerra
    5. A novel phenotype of torpedo maculopathy on spectral-domain optical coherence tomography

      A novel phenotype of torpedo maculopathy on spectral-domain optical coherence tomography

      Purpose To present a new phenotype of torpedo maculopathy on spectral domain optical coherence tomography imaging (SD-OCT). Observations A 31-year-old female presented with a multi-partite yellowish lesion in the macula of her left eye, with a central fovea-involving component and a temporal tail-like component. The lesion showed mixed hyper- and hypoautofluorescence on fundus autofluorescence imaging. The fovea-involving component exhibited disruption of ellipsoid zone without outer-retinal cavitation on SD-OCT, consistent with the prior-described type 1 OCT morphology. The temporal tail showed subtle inner choroidal excavation with preservation of the ellipsoid zone and outer-retinal structures. Conclusions Inner choroidal excavation with preservation of ...

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    6. Evaluation of dental caries, tooth crack, and age-related changes in tooth structure using optical coherence tomography

      Evaluation of dental caries, tooth crack, and age-related changes in tooth structure using optical coherence tomography

      Optical coherence tomography (OCT) is an imaging technique that can visualize the internal biological structure without X-ray exposure. Swept-source OCT (SS-OCT) is one of the latest version of OCT, wherein the light source is a tunable laser that sweeps near-infrared wavelength light to achieve real-time imaging. The imaging depth of OCT is highly influenced by the translucency of the medium. The medium that does not transmit light and the deeper structure beyond the range of light penetration depth are not relevant for OCT imaging. In OCT, sound enamel is almost transparent at the OCT wavelength range, and enamel and dentin ...

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    7. Predictors of Rapid Plaque Progression: An Optical Coherence Tomography Study

      Predictors of Rapid Plaque Progression: An Optical Coherence Tomography Study

      Objectives This study sought to identify morphological predictors of rapid plaque progression. Background Two patterns of plaque progression have been described: slow linear progression and rapid step-wise progression. The former pattern will cause stable angina when the narrowing reaches a critical threshold, whereas the latter pattern may lead to acute coronary syndromes or sudden cardiac death. Methods Patients who underwent optical coherence tomography (OCT) imaging during the index procedure and follow-up angiography with a minimum interval of 6 months were selected. Nonculprit lesions with a diameter stenosis of ≥30% on index angiography were assessed. Lesion progression was defined as a ...

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    8. Spontaneous macular hole closure after posterior vitreous detachment in an eye with hyperreflective OCT stress line

      Spontaneous macular hole closure after posterior vitreous detachment in an eye with hyperreflective OCT stress line

      Purpose The aim of this report is to describe a patient who presented with a central hyper-reflective line (HRL) with spectral domain-optical coherence tomography (SD-OCT) after posterior vitreous detachment that evolved to full thickness macular hole (FTMH) with subsequent spontaneous resolution. Observations A 59-year-old patient presented with a history of photopsia and floaters followed by the development of a central scotoma in the right eye (OD). The left eye (OS) was normal. On examination, visual acuity (VA) was 20/20- OD and 20/20 OS. Retinal examination OD was remarkable for a retinal tear, and SD-OCT demonstrated a central HRL ...

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    9. Redox responsive nanoparticle encapsulating black phosphorus quantum dots for cancer theranostics

      Redox responsive nanoparticle encapsulating black phosphorus quantum dots for cancer theranostics

      Effective cancer treatment puts high demands for cancer theranostics. For cancer diagnostics, optical coherence tomography (OCT) technology (including photothermal optical coherence tomography (PT-OCT)) has been widely investigated since it induces changes in optical phase transitions in tissue through environmental changes (such as temperature change for PT-OCT). In this report, redox responsive nanoparticle encapsulating black phosphorus quantum dots was developed as a robust PT-OCT agent. Briefly, black phosphorus quantum dots (BPQDs) are incorporated into cysteine-based poly-(disulfide amide) (Cys-PDSA) to form stable and biodegradable nanoagent. The excellent photothermal feature allows BPQD/Cys-PDSA nanoparticles (NPs) as a novel contrast agent for high-resolution ...

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    10. Choroidal nonperfusion on optical coherence tomography angiography in a case of unilateral posterior segment ocular sarcoidosis misdiagnosed as MEWDS

      Choroidal nonperfusion on optical coherence tomography angiography in a case of unilateral posterior segment ocular sarcoidosis misdiagnosed as MEWDS

      Purpose To report a case of presumed ocular sarcoidosis initially presenting with features of multiple evanescent white dot syndrome (MEWDS) with atypical optical coherence tomography angiography (OCTA) findings. Observations A 23 year-old woman presented with a unilateral central scotoma, photophobia, and decreased visual acuity after a viral illness. Examination of the right eye revealed multiple round white macular spots and stippled granularity at the fovea. Multimodal imaging with fluorescein angiography (FA), indocyanine green angiography (ICG), fundus autofluorescence (FAF), and optical coherence tomography (OCT) was consistent with a diagnosis of MEWDS. However, OCTA demonstrated choriocapillaris (CC) flow deficits, which is not ...

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    11. Optical coherence tomography angiography of astrocytic hamartoma demonstrates intrinsic vascularity

      Optical coherence tomography angiography of astrocytic hamartoma demonstrates intrinsic vascularity

      Purpose To evaluate the findings of astrocytic hamartoma in the setting of gyrate atrophy, including details of optical coherence tomography angiography (OCTA). Observations Multimodal imaging was obtained on a 20-year-old woman with genetically-confirmed gyrate atrophy. Dilated fundus exam was performed, followed by ultra-widefield color and green autofluorescence imaging and OCTA of bilateral peripapillary and optic disc lesions. Clinical and imaging findings were consistent with gyrate atrophy. The bilateral peripapillary and optic disc lesions had a glistening, translucent, and mulberry-like appearance. OCTA imaging of these lesions clearly demonstrated an intrinsic vascular network and hyporeflective spaces within the lesion, which could not ...

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    12. Reference variance and adjustment factor based wave atoms image speckle reduction method for optical coherence tomography images

      Reference variance and adjustment factor based wave atoms image speckle reduction method for optical coherence tomography images

      Speckle noise in optical coherence tomography (OCT) images causes blurring of small targets and structural edges in the image, which reduces the quality of OCT images. To address this problem, a reference variance and adjustment factor based wave atoms image speckle reduction method for OCT images is proposed. First, reference image and adjustment factor were introduced, and reference image speckle noise reference variance was adjusted using adjustment factor to obtain the target image speckle noise variance. Then, a wave atoms threshold equation including the reference variance and the adjustment factor was constructed to obtain an accurate wave atoms noise reduction ...

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    13. A theoretical model for the micron resolution spectral domain optical coherence tomography

      A theoretical model for the micron resolution spectral domain optical coherence tomography

      The resolution and effective imaging depth (EID) of spectral domain optical coherence tomography (OCT) are of great importance for visualizing the fine details of biological tissues. To this end, a theoretical model for the micron resolution spectral domain OCT was proposed with both the temporal coherence and the longitudinal spatial coherence considered. Based on the model, the parameters that influence the axial resolution, the signal intensity and the EID can be quantitatively analyzed. Among all the parameters the focusing effect of objective lens affects the signal intensity most due to the fast broadening of the effective point spread function (PSF ...

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    14. Ex-vivo molecular imaging with Upconversion Nanoparticles (UCNPs) using Photo Thermal Optical Coherence Tomography (PTOCT)

      Ex-vivo molecular imaging with Upconversion Nanoparticles (UCNPs) using Photo Thermal Optical Coherence Tomography (PTOCT)

      We demonstrate the photothermal optical coherence tomography (PTOCT) system, with upconversion nanoparticles (UCNPs) as a molecular probe. We synthesize hydrophilic, biocompatible upconversion nanoparticles (UCNPs) using hydrothermal synthesis. We developed the PTOCT system along with the signal processing tool and applied this technique on animal tissue phantom for targeted imaging. The ‘lock-in detection’ of the amplitude modulated photothermal beam (980 nm), which used to excite the UCNPs was the backbone of the signal processing algorithm. The signal processing was further established in different aspects. As an application part, the diffusion dynamics of the UCNPs was performed inside the tissue to study ...

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    15. Biomimetic remineralization of artificial caries dentin lesion using Ca/P-PILP

      Biomimetic remineralization of artificial caries dentin lesion using Ca/P-PILP

      Objective To assess the ultrastructural change of demineralized dentin collagen during calcium phosphate polymer-induced liquid precursor (Ca/P-PILP) mediated remineralization process and to evaluate the biomimetic remineralization potential of high concentration Ca/P-PILP at demineralized artificial caries dentin lesion, additionally to investigate the bond interfacial integrity as well as the bonding strength of the biomimetic remineralized artificial caries dentin lesion. Methods Demineralized dentin collagen of 5 μm thick was biomimetically remineralized with low, medium concentration Ca/P-PILP for 10 days and high concentration Ca/P-PILP for 10, 15, 20 days. Artificial caries dentin lesion at a thickness of 150 ± 50 ...

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    16. Anterior-segment spectral domain optical coherence tomography in epidermolysis bullosa

      Anterior-segment spectral domain optical coherence tomography in epidermolysis bullosa

      Purpose Assess epidermolysis bullosa (EB)-related corneal pathology using anterior segment optical coherence tomography (AS-OCT) and correlate imaging with clinical metrics in EB patients versus age-matched controls. Methods EB patients and controls were recruited during an EB conference (July 2018) and at Tufts Medical Center (June–August 2019). Subjects completed a questionnaire, had best corrected visual acuity (BCVA) tested, and underwent AS-OCT scanning. Stromal and epithelial thickness were measured. Depth, length, and type of the three largest lesions were assessed by a masked examiner using a novel pathology grading system. Multivariate analysis of AS-OCT findings and clinical metrics was performed ...

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    17. Optical Coherence Tomography of Outer Retinal Hyper-Reflectivity, Neovascularization and Pigment in Type 2 Macular Telangiectasia

      Optical Coherence Tomography of Outer Retinal Hyper-Reflectivity, Neovascularization and Pigment in Type 2 Macular Telangiectasia

      Purpose To investigate the presence of outer retina hyperreflectivity (ORHR) and outer retina neovascularization (ORNV) before pigment proliferation is visible in eyes with macular telangiectasia type 2 (Mactel 2). Design Retrospective study conducted in a cohort of patients from the Mactel project. Patients Thirty-nine Mactel 2 eyes without pigment on color fundus photo (CFP) at presentation were studied during a mean follow-up of 36.6 months (range: 13.8-50.4 months, SD: ± 10 months). Methods All patients routinely underwent Snellen BCVA measurement, CFP, spectral-domain optical coherence tomography (SD-OCT), and OCT angiography (OCTA). The main outcome measures were the BCVA, the ...

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    18. Don't be afraid of the dark - OCT angiography through a black intraocular lens

      Don't be afraid of the dark - OCT angiography through a black intraocular lens

      Purpose To report a case in which optical coherence tomography (OCT) and OCT angiography (OCT-A) allowed imaging of the posterior pole in a patient fitted with a black occlusive intraocular lens (IOL). Observations Following retinal central artery occlusion, a 52-year-old patient suffered from disturbing residual light perception. Occlusive contact lenses blocked the light insufficiently, so that the patient had to rely on an eye patch for relief of symptoms. After no neovascularization had formed during an observation period of 12 months, a black IOL (Morcher 85F) was implanted, blocking wavelengths in the visible spectrum but allowing transmission in the near-infrared ...

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    19. Woven Coronary Artery Anomaly: Optical Coherence Tomography Versus Intravascular Ultrasound

      Woven Coronary Artery Anomaly: Optical Coherence Tomography Versus Intravascular Ultrasound

      Woven coronary artery anomaly is a rare congenital anomaly, and intravascular ultrasound and optical coherence tomography are useful for the diagnosis. We performed both imaging techniques for woven coronary artery anomaly and evaluated which was superior. We concluded that optical coherence tomography was the preferred imaging modality in this case

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    20. Quantitative assessment of macular microvasculature and radial peripapillary capillary plexus in the fellow eyes of patients with retinal vein occlusion using OCT angiography

      Quantitative assessment of macular microvasculature and radial peripapillary capillary plexus in the fellow eyes of patients with retinal vein occlusion using OCT angiography

      Purpose To evaluate the macular microvasculature and radial peripapillary capillary (RPC) plexus in the fellow eyes of patients diagnosed with unilateral retinal vein occlusion (RVO), using optical coherence tomography angiography (OCTA). Methods Seventy-two fellow eyes of patients with unilateral RVO and 74 healthy control eyes were consecutively enrolled. All subjects underwent a complete ophthalmological assessment, including optical coherence tomography (OCT) and OCTA measurements. Foveal avascular zone (FAZ) area, macular vessel density (VD), and perfusion density (PD) of the superficial capillary plexus (SCP) were measured. The perfusion and flux index (FI) of the RPC plexus were measured using a 4.5 ...

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    21. Application of optical frequency domain imaging to recanalized unruptured internal carotid artery aneurysm treated by flow-diverting stent-assisted coiling

      Application of optical frequency domain imaging to recanalized unruptured internal carotid artery aneurysm treated by flow-diverting stent-assisted coiling

      Here we report the application of optical frequency domain imaging (OFDI), a new optical coherence tomography (OCT) device, for intravascular visualization in the treatment of a recanalized unruptured internal carotid artery aneurysm that was treated initially by stent-assisted coil embolization. OFDI revealed malapposition of the stent and lack of neointimal growth at the aneurysm neck, which was treated by deployment of a Pipeline Embolization Device to overlap the stent. An angiogram performed one year after the procedure revealed perfect healing of the aneurysm and OFDI clearly demonstrated good stent apposition and total endothelialization over the aneurysm neck.

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    22. Macular Optical Coherence Tomography Characteristics at 36 weeks Postmenstrual Age in Infants Examined for Retinopathy of Prematurity

      Macular Optical Coherence Tomography Characteristics at 36 weeks Postmenstrual Age in Infants Examined for Retinopathy of Prematurity

      Objective To report our ability to capture, grade reliably and analyze bedside macular optical coherence tomography (OCT) images from preterm infants and relate OCT findings to biological factors and retinopathy of prematurity (ROP) status at a single time window in the STudy of Eye imaging in Preterm infantS (BabySTEPS). Design Prospective observational study Participants Preterm infants eligible for ROP screening, with parental consent for research and a 36±1 weeks postmenstrual age (PMA) visit. Methods We imaged both eyes of preterm infants with an investigational non-contact, handheld swept-source OCT at the time of clinical ROP examinations. Macular OCT features and ...

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    23. Clinicopathologic correlation of aniridia: Optical coherence tomography angiography and histopathologic observations

      Clinicopathologic correlation of aniridia: Optical coherence tomography angiography and histopathologic observations

      Purpose To describe optical coherence tomography angiography (OCTA) findings in a patient with aniridia and correlate with representative histopathology. Observations OCTA images of the macula of a pediatric aniridic patient, who has nystagmus and impaired vision bilaterally, demonstrate a complete absence of the foveal avascular zone in both the superficial and deep vascular complexes (SVC and DVC). In addition, larger superficial blood vessels were found to be abnormally diving from the SVC into the DVC. Similarly, immunofluorescence with confocal microscopy imaging of a retinal histopathology specimen from a 2 month old aniridic patient demonstrated larger vessels diving in the same ...

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    24. Multimodal imaging in optic nerve melanocytoma: Optical coherence tomography angiography and other findings

      Multimodal imaging in optic nerve melanocytoma: Optical coherence tomography angiography and other findings

      Purpose To evaluate optical coherence tomography (OCT), fundus autofluorescence (FAF) imaging and optical coherence tomography angiography (OCTA) as diagnostic tools in optic disc melanocytoma (ODM) and study the differences in peripapillary and macular vascular density in eyes with ODM using OCTA. Methods Patients with ODM were enrolled in this case series. Each patient underwent evaluation of best-corrected visual acuity, slit-lamp biomicroscopy, fundus examination, fundus photography, standard visual field testing, spectral domain OCT, ultrasound B-scan examination, FAF, fluorescein angiography and OCTA. Results Eight patients (three males and five females) with ODM (9 eyes) were enrolled. The largest ODM presented a nodular ...

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