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    1. Comparison of line‐field confocal optical coherence tomography images with histological sections: Validation of a new method for in vivo and non‐invasive quantification of superficial dermis thickness

      Comparison of line‐field confocal optical coherence tomography images with histological sections: Validation of a new method for in vivo and non‐invasive quantification of superficial dermis thickness

      Background Line‐field confocal optical coherence tomography (LC‐OCT) is an imaging technique providing “optical biopsies” of the skin in real time and non‐invasively. At a center optical wavelength of 1.3 µm, this innovative technology can be applied to dermo‐cosmetic product development due to both high image resolution (~2 µm) and sufficient penetration (~0.5 mm). Nevertheless, the precise dermal area analyzed with LC‐OCT has never been identified. In this study, the objective was to compare LC‐OCT images with histological sections of the same area, in order to validate a new method for in vivo ...

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      Mentions: Arnaud Dubois
    2. Retinal microvasculature in pituitary adenoma patients: is optical coherence tomography angiography useful?

      Retinal microvasculature in pituitary adenoma patients: is optical coherence tomography angiography useful?

      Purpose To examine retinal vascular changes in the peripapillary and macular areas in patients with pituitary adenoma (PA) using optical coherence tomography angiography (OCTA). Methods Cross‐sectional, retrospective study of 17 consecutive PA patients and 16 healthy subjects. All patients underwent a neuro‐ophthalmological examination to assess the presence of optic neuropathy (ON). Static automated perimetry (SAP), macular and optic disc structural OCT [retinal nerve fibre layer (RNFL) and ganglion cell complex (GCC) thicknesses] and OCTA were performed. Pituitary adenoma (PA) patients with ON were compared to those without ON and to healthy subjects. Results Optic neuropathy (ON) was found ...

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    3. Stent underexpansion due to heavy coronary calcification resistant to rotational atherectomy: A case for coronary lithoplasty?

      Stent underexpansion due to heavy coronary calcification resistant to rotational atherectomy: A case for coronary lithoplasty?

      Stent underexpansion is frequently observed in calcified coronary lesions and increases the risk of future adverse cardiac events. Current plaquemodification techniques might not be suitable when calcium deposition is circumferential and deep inside the vessel wall. We report a case during which coronary lithoplasty was used as an adjuvant therapy to improve severe stent underexpansion after failed atherectomy and high‐pressure non‐compliant balloon dilatations.

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    4. Vascular changes after vitrectomy for rhegmatogenous retinal detachment: optical coherence tomography angiography study

      Vascular changes after vitrectomy for rhegmatogenous retinal detachment: optical coherence tomography angiography study

      Purpose To analyse the postoperative foveal avascular zone (FAZ) area, superficial vessel density (SVD) and deep vessel density (DVD) and their correlation with functional (best‐corrected visual acuity, BCVA) and anatomical outcomes (foveal macular thickness, FMT) after surgery for rhegmatogenous retinal detachment (RRD) repair. Method Patients with RRD eyes, successfully treated with a single pars plana vitrectomy (PPV) with gas tamponade and a minimum 12 months follow‐up, were re‐examined. Foveal avascular zone (FAZ) area, SVD, DVD and FMT were evaluated by using optical coherence tomography angiography (OCTA) and compared to fellow eye. Results Fifty‐six patients with macula ...

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    5. In vivo detection of tumor boundary using ultrahigh‐resolution optical coherence angiography and fluorescence imaging

      In vivo detection of tumor boundary using ultrahigh‐resolution optical coherence angiography and fluorescence imaging

      Accurate detection of early tumor margin is of great preclinical and clinical implications for predicting the survival rate of subjects and assessing the response of tumor microenvironment to chemotherapy or radiation therapy. Here, we report a multimodality optical imaging study on in vivo detection of tumor boundary by analyzing neoangiogenesis of tumor microenvironment (microangiography), microcirculatory blood flow (optical Doppler tomography) and tumor proliferation (GFP fluorescence). Microangiography demonstrates superior sensitivity (77.7±6.4%) and specificity (98.2±1.7%) over other imaging technologies (e.g. OCT) for tumor margin detection. Additionally, we report longitudinal in vivo imaging of tumor progression ...

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    6. Capillary Refill—The Key to Assessing Dermal Capillary Capacity and Pathology in Optical Coherence Tomography Angiography

      Capillary Refill—The Key to Assessing Dermal Capillary Capacity and Pathology in Optical Coherence Tomography Angiography

      Background/Objectives: Standard optical coherence tomography angiography (OCTA) has been limited to imaging blood vessels actively undergoing perfusion, providing a temporary picture of surface microvasculature. Capillary perfusion in the skin is dynamic and changes in response to the surrounding tissue's respiratory, nutritional, and thermoregulatory needs. Hence, OCTA often represents a given perfusion state without depicting the actual extent of the vascular network. Here we present a method for obtaining a more accurate anatomic representation of the surface capillary network in human skin using OCTA, along with proposing a new parameter, the Relative Capillary Capacity (RCC), a quantifiable proxy for ...

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    7. Quantitative flow ratio virtual stenting and post stenting correlations to post stenting fractional flow reserve measurements from the DOCTORS (Does Optical Coherence Tomography Optimize Results of Stenting) study population

      Quantitative flow ratio virtual stenting and post stenting correlations to post stenting fractional flow reserve measurements from the DOCTORS (Does Optical Coherence Tomography Optimize Results of Stenting) study population

      Objective We sought to evaluate the correlations of pre‐PCI QFR analysis with virtual PCI called residual QFR and post‐PCI QFR compared to post‐PCI FFR. Background Quantitative flow ratio (QFR) is a computation of fractional flow reserve (FFR) based on angiography without use of a pressure wire. The ability to evaluate post‐PCI FFR using pre‐PCI QFR analysis with a virtual PCI and the correlation between post‐PCI QFR compared to post‐PCI FFR remains unknown. Methods From the DOCTORS (Does Optical Coherence Tomography Optimize Results of Stenting) study population, we blindly analyzed residual QFR and post ...

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    8. Full‐field swept‐source optical coherence tomography and neural tissue classification for deep brain imagingv

      Full‐field swept‐source optical coherence tomography and neural tissue classification for deep brain imagingv

      Optical coherence tomography can differentiate brain regions with intrinsic contrast and at a micron scale resolution. Such a device can be particularly useful as a realtime neurosurgical guidance tool. We present, to our knowledge, the first full‐field swept‐source optical coherence tomography system operating near a wavelength of 1310 nm. The proof‐of‐concept system was integrated with an endoscopic probe tip, that is compatible with deep brain stimulation keyhole neurosurgery. Neuroimaging experiments were performed on ex vivo brain tissues and in vivo in rat brains. Using classification algorithms involving texture features and optical attenuation, images were successfully classified ...

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    9. The Use of Optical Coherence Tomography and Convolutional Neural Networks to Distinguish Normal and Abnormal Oral Mucosa

      The Use of Optical Coherence Tomography and Convolutional Neural Networks to Distinguish Normal and Abnormal Oral Mucosa

      Incomplete surgical resection of head and neck squamous cell carcinoma (HNSCC) is the most common cause of local HNSCC recurrence. Currently, surgeons rely on pre‐operative imaging, direct visualization, palpation, and frozen section to determine the extent of tissue resection. It has been demonstrated that optical coherence tomography (OCT), a minimally invasive, non‐ionizing near infrared mesoscopic imaging modality can resolve subsurface differences between normal and abnormal head and neck mucosa. Previous work has utilized 2‐D OCT imaging which is limited to the evaluation of a small regions of interest generated frame by frame. OCT technology is capable of ...

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    10. Intravascular ultrasound, optical coherence tomography, and fractional flow reserve use in acute myocardial infarction

      Intravascular ultrasound, optical coherence tomography, and fractional flow reserve use in acute myocardial infarction

      Background There are limited data on the use of intravascular ultrasound (IVUS), optical coherence tomography (OCT), and fractional flow reserve (FFR) during acute myocardial infarction (AMI). Objectives To assess the temporal trends of IVUS, OCT, and FFR use in AMI. Methods A retrospective cohort study from the National Inpatient Sample (2004–2014) was designed to include AMI admissions that received coronary angiography. Administrative codes were used to identify percutaneous coronary intervention (PCI), IVUS, OCT, and FFR. Outcomes included temporal trends, inhospital mortality and resource utilization stratified by IVUS, OCT, or FFR use. Results In 4,419,973 AMI admissions, IVUS ...

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    11. Prospective evaluation of drug eluting self‐apposing stent for the treatment of unprotected left main coronary artery disease: 1‐year results of the TRUNC study

      Prospective evaluation of drug eluting self‐apposing stent for the treatment of unprotected left main coronary artery disease: 1‐year results of the TRUNC study

      Objectives To assess long‐term safety and efficacy of the Xposition S self‐apposing stent in the treatment of unprotected left main coronary artery (ULMCA) disease. Background Percutaneous intervention with stents has emerged as a valid alternative to surgical revascularization to treat ULMCA disease. Conventional balloon‐expandable stents face technical challenges, particularly in large left main diameter requiring extensive optimization and side branch access in distal bifurcation. Xposition S allows for optimal apposition, bridging diameter differences, and allows expansion to vessel diameters up to 6.0 mm. Methods Between June 2016 and July 2017, 205 patients were enrolled in this ...

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    12. Clinical validation of the RTVue optical coherence tomography angiography image quality indicators

      Clinical validation of the RTVue optical coherence tomography angiography image quality indicators

      Importance All automated image quality indicators for en face optical coherence tomography angiography (OCTA) images require gold standard validation for determining optimal thresholds. Background A manual grading system (gold standard) for OCTA images was validated and compared to two automated image quality indicators: signal strength index (SSI) and scan quality index (SQI) generated by different software versions of the Optovue OCTA device. Design Retrospective cross‐sectional study. Participants 52 eyes of 52 healthy individual and 77 eyes of 51 patients with retinal vascular diseases. Methods 129 OCTA images of the superficial vascular plexus were graded manually by 3 independent examiners ...

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    13. Simultaneous detection of cerebral blood perfusion and cerebral edema using swept‐source optical coherence tomography

      Simultaneous detection of cerebral blood perfusion and cerebral edema using swept‐source optical coherence tomography

      The progression of ischemic cerebral edema (CE) is closely related to the level of cerebral blood perfusion (CBP) and affects each other. Simultaneous detection of CBP and CE is helpful in understanding the mechanisms of ischemic cerebral edema development. In this article, a wide field of view (FOV) SS‐OCT system was used to detect CE status and CBP levels simultaneously in middle cerebral artery occlusion (MCAO) rats. Images reflecting these two physiological states can be reconstructed with only one C‐scan. We quantify these two physiological states into 4 parameters, which contain two vascular parameters (vascular displacement distance and ...

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    14. Evaluation of different Swept’Source optical coherence tomography angiography (SS‐OCTA) slabs for the detection of features of diabetic retinopathy

      Evaluation of different Swept’Source optical coherence tomography angiography (SS‐OCTA) slabs for the detection of features of diabetic retinopathy

      Purpose To compare different Swept‐Source optical coherence tomography angiography (SS‐OCTA) slabs for the detection of features of diabetic retinopathy (DR), to find the most suitable slab for grading. Methods Retrospective cross‐sectional study. Consecutive patients with DR were evaluated using SS‐OCTA. The central 12 × 12 mm scan was used to generate the retinal, superficial and deep slab. The grading results of the slabs were then compared to determine if one specific slab is superior to detect respective features. Results A total of 348 eyes (190 patients; mean age 58.1 ± 14.5 years) were graded for features ...

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      Mentions: Sebastian Wolf
    15. Imaging of Sub‐Endocardial Adipose Tissue and Fiber Orientation Distributions in the Human Left Atrium using Optical Coherence Tomography

      Imaging of Sub‐Endocardial Adipose Tissue and Fiber Orientation Distributions in the Human Left Atrium using Optical Coherence Tomography

      Background Optical coherence tomography (OCT) has the potential to provide real‐time imaging guidance for atrial fibrillation ablation, with promising results for lesion monitoring. OCT can also offer high‐resolution imaging of tissue composition, but there is insufficient cardiac OCT data to inform the use of OCT to reveal important tissue architecture of the human left atrium. Thus, the objective of this study was to define OCT imaging data throughout the human left atrium, focusing on the distribution of adipose tissue and fiber orientation as seen from the endocardium. Methods and Results Human hearts (n=7) were acquired for imaging ...

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    16. Assessment of corneal viscoelasticity using elastic wave optical coherence elastography

      Assessment of corneal viscoelasticity using elastic wave optical coherence elastography

      The corneal viscoelasticity have great clinical significance, such as the early diagnosis of keratoconus. In this work, an analysis method which utilized the elastic wave velocity, frequency and energy attenuation to assess the corneal viscoelasticity is presented. Using phase‐resolved optical coherence tomography, the spatial‐temporal displacement map is derived. The phase velocity dispersion curve and center frequency are obtained by transforming the displacement map into the wavenumber‐frequency domain through the 2D Fast Fourier Transform (FFT). The shear modulus is calculated through Rayleigh wave equation using the phase velocity in the high‐frequency. The normalized energy distribution is plotted ...

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    17. Role of optical coherence tomography for distal left main stem angioplasty

      Role of optical coherence tomography for distal left main stem angioplasty

      Objective The objective is to analyze the acute and midterm angiographic outcome of percutaneous treatment of left main coronary stem (LM‐PCI) guided by optical coherence tomography (OCT). Background LM‐PCI is a complex procedure, and several anatomical factors may impair its outcome. Intravascular imaging is emerging as a useful tool to guide the procedure. Methods We conducted a retrospective analysis of patients undergoing LM‐PCI at three European centers between 2014 and 2017 with a control angiography at 6–12 months. Patients were divided into two groups: OCT‐guidance (pre‐ and post‐PCI) and control group (standard angiographic guidance ...

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    18. Evaluation of surgically excised breast tissue microstructure using wide‐field optical coherence tomography

      Evaluation of surgically excised breast tissue microstructure using wide‐field optical coherence tomography

      Background Currently, positive margins at lumpectomy contribute to health care cost, patient anxiety, and treatment delay. Multiple technology solutions are being explored with the aim of lowering re‐excision rates for breast‐conserving surgery (BCS). We examined wide‐field optical coherence tomography (WF‐OCT), an innovative adjunct intraoperative imaging tool for tissue visualization of margins. Methods This IRB‐approved pilot study included women with invasive or in situ carcinoma scheduled for primary BCS. Lumpectomy specimens and any final/revised margins were imaged by optical coherence tomography immediately prior to standard histological processing. The optical coherence tomography used provided two‐dimensional ...

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