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    1. Atherosclerosis and General Principles of Arterial Imaging

      Atherosclerosis and General Principles of Arterial Imaging

      The imaging of large arteries has expanded during recent years, both for clinical purposes and for research. The technical development has been very impressive. By the use of these modern technologies, it has been possible to achieve a better understanding of atherosclerosis and its morphology and mechanical interactions with the bloodstream. In addition, the imaging of large arteries, especially the aorta, has shed new light on the development of the changes in the arterial media linked to arterial stiffness, increased pulse wave velocity and arterial ageing. In this chapter, these aspects are discussed for atherosclerosis in general and for the ...

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    2. Retinal nerve fiber layer and ganglion cell complex thicknesses measured with spectral-domain optical coherence tomography in eyes with no light perception due to nonglaucomatous optic neuropathy

      Retinal nerve fiber layer and ganglion cell complex thicknesses measured with spectral-domain optical coherence tomography in eyes with no light perception due to nonglaucomatous optic neuropathy

      PURPOSE: To measure retinal nerve fiber layer thickness (RNFLT) and ganglion cell complex thickness (GCCT) in eyes with no light perception due to nonglaucomatous optic neuropathy using spectral-domain optical coherence tomography. METHODS: Fourteen eyes of 14 patients (9 women, 5 men; mean age 56.0 ± 16.6 (standard deviation) years] with no light perception due to optic neuropathy were recruited to this retrospective study. Only clinically stable eyes were included. Eyes were imaged at least 6 months after the onset of the disease. Five patients lost light perception due to traumatic optic neuropathy, four patients had ischemic optic neuropathy, two ...

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    3. Macular morphologic findings on optical coherence tomography after microincision vitrectomy for proliferative diabetic retinopathy

      Macular morphologic findings on optical coherence tomography after microincision vitrectomy for proliferative diabetic retinopathy

      Purpose To investigate macular morphology on spectral-domain optical coherence tomography (SD-OCT) images after microincision vitrectomy for vitreous hemorrhage associated with proliferative diabetic retinopathy (PDR). Methods In this retrospective case series, 69 eyes (57 consecutive patients) that underwent 23-gauge microincision vitrectomy for vitreous hemorrhage due to PDR were investigated. Qualitative and quantitative characteristics on SD-OCT images [central retinal thickness, external limiting membrane (ELM), and the ellipsoid zone, epiretinal membranes involving the fovea, and hyperreflective foci at the fovea] were assessed 6 months postoperatively. Their association with the logarithm of the minimum angle of resolution visual acuity (logMAR VA) was evaluated. Results ...

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    4. Real-life experience after intravitreal ocriplasmin for vitreomacular traction and macular hole: a spectral-domain optical coherence tomography prospective study

      Real-life experience after intravitreal ocriplasmin for vitreomacular traction and macular hole: a spectral-domain optical coherence tomography prospective study

      Purpose To evaluate prospectively the anatomical and functional results after ocriplasmin injection in patients with vitreomacular traction (VMT), or macular hole (MH) combined with VMT, providing the real-life experience of three centers, using spectral domain-optical coherence tomography (SD-OCT). Methods Twenty-four patients with VMT (17 with VMT alone and 7 with an MH combined with VMT) were treated with a single ocriplasmin injection and followed-up prospectively at baseline, day 1, 7, 28 and the last examination of the follow-up for each patient (range: 30–127 days). Best-corrected visual acuity (BCVA) and SD-OCT were performed for patient assessment, while various adverse events ...

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    5. Accurate velocity measurements of boundary-layer flows using Doppler optical coherence tomography

      Accurate velocity measurements of boundary-layer flows using Doppler optical coherence tomography

      Pulsed ultrasound Doppler velocimetry and nuclear magnetic resonance imaging are popular non-invasive measurement methods for flows of opaque fluids. The spatial and temporal resolution of these methods, however, is quite limited, and they lack accuracy, especially close to solid boundaries. In this paper, we show that solution to these problems is achieved by using Doppler optical coherence tomography (DOCT). DOCT provides simultaneous information about the fluid structure and velocity with very high spatial and temporal resolution. For benchmarking of the method we use water as the reference fluid. We show how DOCT gives a very good agreement with theory for ...

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    6. Optimizing flushing parameters in intracoronary optical coherence tomography: an in vivo swine study

      Optimizing flushing parameters in intracoronary optical coherence tomography: an in vivo swine study

      Intracoronary optical frequency domain imaging (OFDI), requires the displacement of blood for clear visualization of the artery wall. Radiographic contrast agents are highly effective at displacing blood however, may increase the risk of contrast-induced nephropathy. Flushing media viscosity, flow rate, and flush duration influence the efficiency of blood displacement necessary for obtaining diagnostic quality OFDI images. The aim of this work was to determine the optimal flushing parameters necessary to reliably perform intracoronary OFDI while reducing the volume of administered radiographic contrast, and assess the influence of flushing media choice on vessel wall measurements. 144 OFDI pullbacks were acquired together ...

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    7. PEGylated Aucore–Agshell Nanorods as Optical Coherence Tomography Signal Nanoamplifiers

      PEGylated Aucore–Agshell Nanorods as Optical Coherence Tomography Signal Nanoamplifiers

      Optimizing contrast enhancement in optical coherence tomography (OCT) is essential for producing specific image signals and realizing its potential use in various biomedical imaging fields besides ophthalmology and cardiology. Using nanoparticles as selective signal nanoamplifiers will be helpful to highlight the lesion sites and identify cancerous changes that are difficult to diagnose currently. In this study, a quantitatively detailed analysis on the improvement of contrast enhancement and penetration depth of Au core –Ag shell nanorods (Au@Ag NRs) as OCT contrast agent was performed. The average A-scan data of the tissue was extracted and investigated. The signal to noise ratio ...

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    8. Central corneal thickness determination in corneal edema using ultrasound pachymetry, a Scheimpflug camera, and anterior segment OCT

      Central corneal thickness determination in corneal edema using ultrasound pachymetry, a Scheimpflug camera, and anterior segment OCT

      Purpose The purpose of this study is to determine the influence of post-surgical corneal edema on the reliability and reproducibility of central corneal thickness (CCT) measurements by a Scheimpflug camera (Pentacam), ultrasound pachymetry (USP), and anterior-segment spectral-domain optical coherence tomography (AS-OCT). Methods Thirty-two patients planned for cataract surgery ( n  = 16) or vitrectomy ( n  =  6) were included in a prospective study. The non-surgery eye was used as control. Two investigators acquired two measurements each, with the Pentacam (Oculus, Germany) and the AS-OCT (Heidelberg Engineering, Germany) in a randomized order, followed by USP (Tomey SP-100, Germany). CCT was evaluated using the apex ...

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    9. Detecting signs of retinal leakage in exudative AMD using Cirrus OCT versus SL SCAN-1, a novel integrated FD-OCT into a common slit lamp

      Detecting signs of retinal leakage in exudative AMD using Cirrus OCT versus SL SCAN-1, a novel integrated FD-OCT into a common slit lamp

      Purpose The purpose is to evaluate the interdevice and interobserver agreements between the SL SCAN-1 (a FD-OCT integrated into a common slit lamp) and a standard stand-alone FD-OCT device (the Cirrus ) with regard to the presence or absence of signs of leakage in the retina in patients with exudative AMD and treated with anti- VEGF . Methods Fifty-six patients, known to have exudative AMD and under treatment with anti- VEGF agents, were included. During a regular follow-up, OCT scans were made with the Cirrus (macular-cube pattern) and the SL SCAN-1 (radial-scan pattern). All scans were graded by two medical retina specialists ...

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    10. In-vivo mapping of drusen by fundus autofluorescence and spectral-domain optical coherence tomography imaging

      In-vivo mapping of drusen by fundus autofluorescence and spectral-domain optical coherence tomography imaging

      Purpose To determine fundus autofluorescence (FAF) signal variations and corresponding microstructural alterations on spectral-domain optical coherence tomography (SD-OCT) in areas of funduscopically visible drusen associated with age-related macular degeneration (AMD). Methods Thirty eyes from 22 patients with geographic atrophy (GA) secondary to AMD (median age 74, range 64–87 years), who had undergone retinal imaging including color fundus photography (CFP), FAF and SD-OCT (Spectralis HRA+OCT; Heidelberg Engineering GmbH, Heidelberg, Germany) were retrospectively analyzed. In each eye, at least one druse (≥63 μm) in the perilesional zone of GA recorded on CFP was analyzed. Relative FAF intensities and alterations in ...

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    11. Swept source optical coherence tomography of the posterior vitreous after pars plana vitrectomy

      Swept source optical coherence tomography of the posterior vitreous after pars plana vitrectomy

      Dear Editor, Swept source optical coherence tomography (SS-OCT) visualizes deep structures such as the choroid, sclera, and most recently, the vitreous at the posterior pole [ 1 ]. With a light wavelength of 1050 nm and scanning speed of 100,000 Hz, SS-OCT has several advantages over spectral domain OCT (SD-OCT), including improved penetration through opacities, faster acquisition times while maintaining high-quality images, and a wider field than SD-OCT (12 mm vs. 6 mm) [ 2 – 4 ]. SS-OCT can provide helpful high-resolution imaging when looking at vitreous pathology [ 4 – 6 ]. Herein, we present two cases where SS-OCT was beneficial in evaluating the vitreous ...

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    12. Neointimal coverage and late apposition of everolimus-eluting bioresorbable scaffolds implanted in the acute phase of myocardial infarction: OCT data from the PRAGUE-19 study

      Neointimal coverage and late apposition of everolimus-eluting bioresorbable scaffolds implanted in the acute phase of myocardial infarction: OCT data from the PRAGUE-19 study

      Incomplete stent apposition and uncovered struts are associated with a higher risk of stent thrombosis. No data exist on the process of neointimal coverage and late apposition status of the bioresorbable vascular scaffold (BVS) when implanted in the highly thrombogenic setting of ST-segment elevation acute myocardial infarction ( STEMI ). The aim of this study was to assess the serial changes in strut apposition and early neointimal coverage of the BVS using optical coherence tomography (OCT) in selected patients enrolled in the PRAGUE-19 study. Intracoronary OCT was performed in 50 patients at the end of primary percutaneous coronary intervention for acute STEMI ...

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    13. Spectral-domain optical coherence tomography reveals prelaminar membranes in optic nerve head pallor in eyes with retinitis pigmentosa

      Spectral-domain optical coherence tomography reveals prelaminar membranes in optic nerve head pallor in eyes with retinitis pigmentosa

      Purpose To determine the relationship between prelaminar structural changes of the optic nerve head (ONH) and optic nerve waxy pallor in retinitis pigmentosa (RP) using spectral-domain optical coherence tomography (SD-OCT) and fundus photography. Methods An observational cross-sectional case control study of patients with RP with and without ONH waxy pallor and controls. Subjects underwent clinical examination, fundus photography, and SD-OCT raster imaging of the ONH. Four independent specialists reviewed the images in a masked fashion. Results Fifty-five eyes of 31 subjects with RP and 28 eyes of 14 controls were included. Optic nerve head waxy pallor was seen in 29 ...

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    14. Technology developments and biomedical applications of polarization-sensitive optical coherence tomography

      Technology developments and biomedical applications of polarization-sensitive optical coherence tomography

      Polarization-sensitive optical coherence tomography (PS-OCT) enables depth-resolved mapping of sample polarization information, such as phase-retardation and optical axis orientation, which is particularly useful when the nano-scale organization of tissue that are difficult to be observed in the intensity images of a regular optical coherence tomography (OCT). In this review, we survey two types of methods and systems of PS-OCT. The first type is PS-OCT with single input polarization state, which contain bulk optics or polarization maintaining fiber (PMF) based systems and single-mode fiber (SMF) based systems. The second type is PS-OCT with two different input polarization states, which contain SMF ...

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    15. Longitudinal analysis of the structural pattern of pseudophakic cystoid macular edema using multimodal imaging

      Longitudinal analysis of the structural pattern of pseudophakic cystoid macular edema using multimodal imaging

      Purpose To describe the relationship between pseudophakic cystoid macular edema (CME) progression and retinal structural changes observed by spectral-domain optical coherence tomography (SD-OCT) and fluorescein angiography. Methods Retrospective, consecutive, longitudinal imaging analysis of patients with acute pseudophakic cystoid macular edema. Two observers at two study centers evaluated all images and categorized the macular structural features based on the retinal layer involved with cystic changes and/or subretinal fluid. A time series of the structural pattern and visual acuity was constructed for 1-month intervals over a 6-month study period. Results Thirty nine patients presented with CME. The mean time since cataract ...

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    16. Analysis of the ganglion cell layer and photoreceptor layer using optical coherence tomography after idiopathic epiretinal membrane surgery

      Analysis of the ganglion cell layer and photoreceptor layer using optical coherence tomography after idiopathic epiretinal membrane surgery

      Dear Editor, We appreciate Dr. Iuliano for his interest and comments regarding our article, and we are pleased to share our opinions regarding visual prognosis after epiretinal membrane (ERM) surgery. Studies from Dr. Iuliano’s group and our group have shown that the ganglion cell layer (GCL) is a significant factor in determining visual acuity in idiopathic ERM [ 1 , 2 ]. A decrease in the thickness of the GCL was correlated with postoperative visual recovery in their study,[ 1 ] whereas thinning of the GCL was correlated with poor visual acuity in our study [ 2 ]. We agree with Dr. Iuliano’s comment ...

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    17. Impact of drug-eluting balloon (pre- or post-) dilation on neointima formation in de novo lesions treated by bare-metal stent: the IN-PACT CORO trial

      Impact of drug-eluting balloon (pre- or post-) dilation on neointima formation in de novo lesions treated by bare-metal stent: the IN-PACT CORO trial

      The efficacy of DEB in modifying the high restenosis risk associated with BMS implantation is doubtful. Optical coherence tomography (OCT) may allow precise assessment of neointimal formation after stent implantation. We performed a single-center, prospective, 1:2 randomized trial comparing BMS implantation alone (BMS group) vs. additional DEB (DEB group). DEB patients were further randomized 1:1 to DEB before stenting (pre-DEB group), or after stenting (post-DEB group). Primary endpoint was OCT-assessed neointimal hyperplasia (expressed both as mean in-stent neointimal area and as percentage obstruction of the mean stent area) at 6 months. Secondary endpoints were the percentage of uncovered ...

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      Mentions: Francesco Prati
    18. Neoatherosclerosis causing edge in-stent restenosis: optical coherence tomography findings

      Neoatherosclerosis causing edge in-stent restenosis: optical coherence tomography findings

      A patient presenting with ‘edge’ in-stent restenosis 12 years after the implantation of a bare-metal stent in the mid-left anterior descending coronary artery is described. Optical coherence tomography disclosed the presence of ruptured neoatherosclerosis at the stent edge. The value of this imaging technique to unravel this unique underlying anatomic substrate is discussed. The therapy of choice for patients presenting with edge in-stent restenosis (ISR) is reviewed.

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      Mentions: Fernando Alfonso
    19. Application of Optical Coherence Tomography (OCT) for Diagnosis of Caries, Cracks, and Defects of Restorations

      Application of Optical Coherence Tomography (OCT) for Diagnosis of Caries, Cracks, and Defects of Restorations

      Optical coherence tomography (OCT) is a noninvasive technique providing cross-sectional images of a tooth structure. This review describes the use of OCT for detecting dental caries, tooth fractures, and interfacial gaps in intraoral restorations. OCT can be a reliable and an accurate method and a safer alternative to X-ray radiography.

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    20. Vascular distribution imaging of dorsal skin window chamber in mouse with spectral domain optical coherence tomography

      Vascular distribution imaging of dorsal skin window chamber in mouse with spectral domain optical coherence tomography

      Doppler optical coherence tomography or optical Doppler tomography (ODT) has been demonstrated to spatially localize flow velocity mapping as well as to obtain images of microstructure of samples simultaneously. In recent decades, spectral domain Doppler optical coherence tomography (OCT) has been applied to observe three-dimensional (3D) vascular distribution. In this study, we developed a spectral domain optical coherence tomography system (SD-OCT) using super luminescent diode (SLD) as light source. The center wavelength of SLD is 835 nm with a 45-nm bandwidth. Theoretically, the transverse resolution, axial resolution and penetration depth of this SD-OCT system are 6.13 μm, 6.84 ...

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    21. Comparison of the current and a new RTVue OCT software version for detection of ganglion cell complex changes due to cataract surgery

      Comparison of the current and a new RTVue OCT software version for detection of ganglion cell complex changes due to cataract surgery

      The purpose was to compare the current (6.3) and a novel software version (6.12) of the RTVue-100 optical coherence tomograph (RTVue OCT) for ganglion cell complex (GCC) and retinal nerve fibre layer thickness (RNFLT) changes after phacoemulsification in healthy cataract eyes, and to investigate whether version 6.12, in which image segmentation is improved, provides benefits over version 6.3 for RNFLT and GCC imaging via mild cataract. One eye of 22 consecutive healthy cataract patients were imaged before and 1 month after uncomplicated cataract surgery using RTVue-100 OCT software version 6.3. The images were analysed with ...

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    22. Spectral domain optical coherence tomography imaging of tubercular chorioretinitis and intraretinal granuloma. Intraretinal tuberculosis: a case report

      Spectral domain optical coherence tomography imaging of tubercular chorioretinitis and intraretinal granuloma. Intraretinal tuberculosis: a case report

      The aim of this study is to report the clinical and spectral domain optical coherence tomography (SD-OCT) findings in a patient suffering from ulcerative colitis with bilateral tubercular chorioretinitis and intraretinal granuloma regressed with systemic antitubercular therapy (ATT). This study is a case report of a 33-year-old Bangladeshi male with ulcerative colitis treated with oral corticosteroids and azathioprine who was referred to our department with a diagnosis of central serous chorioretinopathy. Serological tests, the Mantoux skin test, complete ophthalmologic examination, ocular fundus photography, fundus fluorescein angiography, and SD-OCT scans were performed. The ophthalmological inflammatory pattern and serological investigations provided an ...

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    23. Applicability of the ISNT and IST rules on retinal nerve fiber layer measurement on spectral-domain optical coherence tomography in normal Indian children

      Applicability of the ISNT and IST rules on retinal nerve fiber layer measurement on spectral-domain optical coherence tomography in normal Indian children

      Background To determine the applicability of the ISNT (inferior>superior>nasal>temporal) and IST (inferior>superior>temporal) rules on retinal nerve fiber layer (RNFL) measurement on spectral-domain optical coherence tomography (SD-OCT) in normal children. Methods A prospective, cross-sectional study including consecutive subjects between the ages of 5–18 years who were born at term (≥37 weeks gestational age) and with a normal birth weight (≥2500 g) presenting to the out-patient department for refractive error examination. RNFL measurement was done on Spectralis SD-OCT. Exclusion criteria were best-corrected visual acuity less than 20/20, spherical equivalent (SE) > ± 5 diopter (D), applanation IOP ...

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    24. Correlation between depth and area of retinal nerve fiber layer defect as measured by spectral domain optical coherence tomography

      Correlation between depth and area of retinal nerve fiber layer defect as measured by spectral domain optical coherence tomography

      Background To evaluate the correlation between the depth and area of retinal nerve fiber layer (RNFL) defect, as measured on an RNFL map of spectral-domain optical coherence tomography (SD-OCT). Methods The RNFL of 472 glaucoma subjects and of 217 healthy subjects was imaged by an SD-OCT. RNFL defect depth and area on the RNFL map were expressed as an RNFL defect depth percentage index (RDPI) and an RNFL defect area index (RDAI), respectively, according to the following two formulas: 100×[1–{summation of thicknesses of RNFL defects/summation of thicknesses of upper 95th percentile range of age-matched healthy subjects in ...

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