In this study, the efficacy of phycocyanin in bone defect repairing was tested on a zebrafish skull defect model, and the evaluating process was monitored in vivo using optical coherence tomography (OCT). Thirty zebrafish were randomly divided into three groups, which were immersed in water and phycocyanin solution (50 mg/L and 100 mg/L) after skull defect creating. All zebrafish were examined by OCT immediately after craniotomy, and on the 10th and 20th days of phycocyanin treatment. All the model fish were euthanized to enable a histological evaluation of skull after 20 days recovery. OCT images demonstrated that phycocyanin ...

Purpose To evaluate the inner layers of the retina in patients with fibromyalgia (FM) compared to healthy subjects using a posterior pole protocol analysis in optical coherence tomography (OCT) and the relationship of structural measures with quality of life. Methods Seventy-four eyes of healthy subjects and 55 eyes of FM patients were analyzed. FM group was divided into three subgroups depending on the phenotype of the disease (group 1, biologic phenotype; group 2, depressive phenotype; group 3, atypical phenotype). All of them were evaluated using Pole Posterior protocol of OCT Spectralis, which analyzes the thickness of the macular area divided ...

Purpose To determine the specific changes in the parameters of electroretinography (ERG), reflecting various aspects of retinal ganglion cell (GC) function, and optical coherence tomography (OCT), and their correlations in patients with advanced stages of primary open-angle glaucoma (POAG). Methods The study included 35 people (55 eyes) with stages II and III POAG, divided into two subgroups, and 28 healthy age-matched individuals (32 eyes). Transient and stationary pattern-electroretinograms (PERG) and photopic negative response (PhNR) were recorded according to the ISCEV Standards (RETIport/scan, Roland Consult). The thickness of the GC complex (GCC) of the macular region was assessed (Heidelberg Spectralis ...

Purpose To assess the longitudinal changes of neovascularisations (NV) in a patient with proliferative diabetic retinopathy (PDR) after panretinal photocoagulation under additive intravitreal treatment with Vascular Endothelial Growth Factor (VEGF)-inhibitors using optical coherence tomography angiography (OCTA). Methods We present two patients after several sessions of panretinal photocoagulation and intravitreal treatment with VEGF-Inhibitors due to DME and also to treat PDR. Multimodal imaging including fundus photography and optical coherence tomography angiography (OCTA) was used to monitor the effect of VEGF-inhibitors on the NV. We measured the size of the NV at baseline and at 1, 3, and 6 months and ...

Purpose To analyze the vitreous opacities of rat eyes by optical coherence tomography (OCT) in two models of chronic glaucoma. Hyperreflective opacities at the vitreoretinal interface, their dynamics over time (changes in number, size, intensity, eccentricity, and orientation) and as a function of intraocular pressure were analyzed in two different glaucoma models and compared to healthy controls. Methods Images of the vitreoretinal interface were obtained by OCT and exported as videos (composed of cross-sectional images acquired by means of 61 b-scans measuring around 3 mm in length and centred on the optic nerve). These videos were analysed using a custom ...

Dear Editors, Alopecia areata (AA) is an autoimmune skin disorder that affects any hair-bearing areas and results in localized nonscarring hair loss. It can occur in individuals at any age regardless of ethnicity with a lifetime risk of 1–2%. 1 The loss of hair is caused by perifollicular inflammation, which is associated with cytokines and chemokines released by T cells. 2 , 3 Although spontaneous regrowth is possible in 80% of patchy AA, full resolution is slow. 4 Patients with AA can be treated with various treatment options including a topical or intralesional steroid. While intralesional steroid injection is more ...

Optical coherence tomography angiography (OCTA) can map microvascular networks and quantify blood flow velocities with high resolution by calculating intensity standard deviations of time-series signals. However, statistical calculations of the standard deviations need much processing time and reduce the analysis efficiency. In this study, we proposed three optimized OCTA algorithms incorporating rapid estimations of the intensity standard deviations, including the range algorithm, the mean absolute error algorithm, and the maximum absolute error algorithm. The abilities of the optimized algorithms to quantify the flow velocities were validated by a flow phantom. After a rat cerebral cortex was imaged, the optimized OCTA ...

Carbon dots (CDs) have been considered as promising candidates with superior biocompatibilities for multimodel cancer theranostics. However, incorporation of exogenous components, such as targeting molecules and chemo/photo therapeutic drugs, are often required to improve the therapeutic efficacy. Herein, we propose an "all-in-one" CDs that exhibit intrinsic bioactivities for bioimaging, potent tumor therapy and postoperative management. The multifunctional CDs derived from gallic acid and tyrosine (GT-CDs) consist of a graphitized carbon core and N, O-rich functional groups, which endow them with a high near-infrared photothermal conversion efficiency of 33.9% and tumor-specific cytotoxicity, respectively. A new imaging modality, photothermal optical ...

Light in the second near-infrared (NIR-II) window in the wavelength range of 1000 – 1700 nm shows reduced absorption by biological tissues, scattering, and auto- fl uorescence, compared with light in the visible region. [1 – 3] These characteristics result in a deep biological tissue penetra- tion depth and high-resolution images during in vivo imaging. [4 – 6] Therefore, con- siderable research is ongoing regarding contrast agents for in vivo NIR-II window imaging applications, such as single-walled carbon nanotubes, quantum dots, and Au nanoparticles. Single-walled carbon nano- tubes are 1D nanomaterials with a bandgap of approximately 1 eV, which can be used as ...

Letter to the editor

Objectives/hypothesis: To establish the utility of anatomic optical coherence tomography (aOCT) in evaluating internal nasal valve (INV). Study design: Anatomic specimen imaging study. Methods: Fresh-harvested human specimen heads were evaluated using both computed tomography (CT) imaging as well as using aOCT. Scans were performed at three time points: 1) After septoplasty for cartilage harvest, 2) after placement of butterfly graft (BFG), and 3) after placement of bilateral spreader grafts (SG). Imaging data were then converted into 3D models of the nasal airway. CT- and aOCT-generated models were compared by both static volumetric analysis and computational fluid dynamics (CFD) to ...

Introduction: Port-wine birthmarks (PWBs) are congenital capillary malformations that can be located on any area of the body. Vascular features include vessel size, depth, and density, which can greatly differ between patients, individual lesions, and even sites within the same lesion. Previous studies have determined that the location of PWB lesions has impacted their clinical response to laser treatment. Objective: We utilized dynamic optical coherence tomography (D-OCT) to measure in vivo vessel diameter, density, and superficial plexus depth in patients of all ages with PWB on various sites of the body. We hypothesized that these vascular characteristics would differ according ...

Purpose: To investigate the response of the superficial and deep capillary plexuses to hyperoxia and hypoxia using optical coherence tomography angiography (OCT-A) and retinal vessel analyzer. Methods: Twenty-four healthy volunteers participated in this randomized, double-masked, cross-over study. For each subject, two study days were scheduled: on one study day, hyperoxia was induced by breathing 100% oxygen whereas on the other study day, hypoxia was induced by breathing a mixture of 88% nitrogen and 12% oxygen. Perfusion density was calculated in the superficial vascular plexus (SVP) and the deep capillary plexus (DCP), using OCT-A before (normal breathing) and during breathing of ...

In vivo volumetric imaging of the microstructural changes of peripheral nerves with an inserted electrode could be key for solving the chronic implantation failure of an intra-neural interface necessary to provide amputated patients with natural motion and sensation. Thus far, no imaging devices can provide a cellular-level three-dimensional (3D) structural images of a peripheral nerve in vivo. In this study, an optical coherence tomography-based peripheral nerve imaging platform that employs a newly proposed depth of focus extension technique is reported. A point spread function with the finest transverse resolution of 1.27 µm enables the cellular-level volumetric visualization of the ...

Objective: To evaluate changes over 3 years in the thickness of inner retinal layers including the peripapillary retinal nerve fiber layer (pRNFL), and combined macular ganglion cell and inner plexiform layers (mGCIPL), in individuals with relapsing-remitting multiple sclerosis (RRMS) versus healthy controls; to determine whether optical coherence tomography (OCT) is sufficiently sensitive and reproducible to detect small degrees of neuroaxonal loss over time that correlate with changes in brain volume and disability progression as measured by the Expanded Disability Status Scale (EDSS). Methods: Individuals with RRMS from 28 centers (n = 333) were matched with 64 healthy participants. OCT scans were ...

Objective: To describe the in vivo structural characteristics of multifocal and geographic retinal dysplasia visualized with advanced retinal imaging including confocal scanning laser ophthalmoscopy (cSLO), optical coherence tomography (OCT), en face OCT, and the novel vascular imaging technique OCT angiography (OCTA). Dogs studied and procedures: Two dogs were diagnosed with unilateral multifocal or geographic retinal dysplasia and underwent advanced retinal imaging under general anesthesia at the Retinal Disease Studies Facility of the University of Pennsylvania. Results: In both cases, the morphological pattern of the lesions was similar including outer retinal folds that invaginated and formed tubular retinal rosettes, surrounding a ...

Objective: To evaluate the clinical application of spectral-domain optical coherence tomography (SD-OCT) for anterior uveitis in dogs. Animals and procedures: Client-owned dogs presenting with anterior uveitis and clinically healthy dogs were enrolled in this study. Included eyes were divided into 5 groups by flare grade and 3 groups by cell grade through slit-lamp biomicroscopy. Each eye was examined using SD-OCT following slit-lamp biomicroscopy. The ratio of aqueous signal intensity to air signal intensity, which is called the aqueous-to-air relative intensity (ARI) index, was used to evaluate the flare grade. Cell number, central corneal thickness (CCT), and the presence of keratic ...

Objective: To evaluate changes over 3 years in the thickness of inner retinal layers including the peripapillary retinal nerve fiber layer (pRNFL), and combined macular ganglion cell and inner plexiform layers (mGCIPL), in individuals with relapsing-remitting multiple sclerosis (RRMS) versus healthy controls; to determine whether optical coherence tomography (OCT) is sufficiently sensitive and reproducible to detect small degrees of neuroaxonal loss over time that correlate with changes in brain volume and disability progression as measured by the Expanded Disability Status Scale (EDSS). Methods: Individuals with RRMS from 28 centers (n = 333) were matched with 64 healthy participants. OCT scans were ...

Aims We evaluated the first in-human performance of a novel hybrid imaging catheter that permits simultaneous and co-registered acquisition of intravascular ultrasound (IVUS) and optical coherence tomography (OCT) images. Methods and Results A total of 17 patients undergoing planned percutaneous coronary intervention (PCI) were imaged between August 2018 and August 2019. Eleven patients with both pre- and post-PCI IVUS and OCT images were included in the offline image analysis. IVUS and OCT images were analyzed separately then together with co-registered images for pre-stent findings, and only separately for post-stent findings. A total of 926 frames were analyzed (218 pre-PCI, 708 ...

Objective: To compare the measurements of iridocorneal angle parameters between spectral domain optical coherence tomography (SD-OCT) and ultrasound biomicroscopy (UBM) in dogs. Animals studied and procedures: A total of 47 eyes of dogs were scanned at the temporal limbus using SD-OCT and UBM. Iridocorneal angle (ICA) and angle opening distance (AOD) were measured from the obtained images accordingly. The intra-observer and inter-observer reproducibility were evaluated using the intraclass correlation coefficient. To evaluate intra-observer reproducibility, measurements of the first and second grading from the first examiner were compared. To evaluate inter-observer reproducibility, measurements between the two examiners were compared. Agreement between ...

Objective: To confirm the feasibility of visualizing upper and lower proximal lacrimal canaliculi (LC) using spectral-domain optical coherence tomography (SD-OCT). Animals studied: Eight eyes of four normal Beagle dogs. Procedures: To obtain an upper proximal LC image, the head was turned in the opposite direction to the eye being imaged, and the medial part of the upper eyelid was everted to expose the LC. To obtain a lower LC image, the lower eyelid was everted just below the punctum. Using "angle mode", the scan line was placed parallel on the long axis of the LC. The inlet LC width (LCW ...

Introduction: Diabetes is a global issue that currently affects 425 million people worldwide. One observable microvascular complication of this condition is a change in the foveal avascular zone (FAZ). In this study, we used optical coherence tomography angiography (OCT-A) to investigate the effect of diabetes on the FAZ. Materials and methods: Eleven diabetic and eleven non-diabetic participants took part in this study. Participants in both groups were matched for age (p = 0.217) and sex (p = 0.338), and had no history of ocular disease. Macular OCT-A scans of participants' right and left eyes were taken. Glycosylated haemoglobin (HbA 1c ...

The diagnostic accuracy of optical coherence tomography (OCT) for in-vivo assessment of resection margins of basal cell carcinoma (BCC) prior to Mohs' Micrographic Surgery (MMS) remains unknown.(1) Therefore, we conducted a multicentre, case-control study with the objective to estimate sensitivity and specificity values. Included were patients with a biopsy proven primary BCC and an indication for MMS (2), who visited the dermatology outpatient clinic of Maastricht University Medical Centre+ or Mohs Klinieken in Hoorn, The Netherlands.

Background and objective: Lasers are widely employed in clinical applications. In vivo monitoring of real-time information about different-wavelength laser surgeries would provide important surgical feedback for surgeons or clinical therapy instruments. However, the quantitative effect of laser ablation or vaporization still needs to be further explored and investigated. Here, we investigate and quantitatively evaluate the ablation variations and morphological changes of two laser ablation models: point- and sweeping-based models. Methods: An infrared thermal imager was used to monitor the temperature variations, and curve fitting was used to build the relationship between the laser radiation duration/sweeping speed and quantitative parameters ...