In this prospective study, we analysed the changes in retinal vessel density (VD) using optical coherence tomography angiography (OCTA) in patients with commotio retinae up to 6 months after blunt ocular trauma. We analysed the VD in the superficial capillary plexus (SCP), deep capillary plexus (DCP), radial peripapillary capillary (RPC) and the foveal avascular zone (FAZ) area at 48 h, and 1, 3 and 6 months after the trauma and compared results with those of healthy fellow eyes. We also evaluated the best-corrected visual acuity (BCVA) and the structural, spectral domain (SD)-OCT parameters: ganglion cell complex (GCC) and retinal ...

The main goal of this research was to assess if it is possible to evaluate the thickness of thin layers (both thin films on the surface and thin layers below the surface of the tested object) and foils using optical coherence tomography (OCT) for thickness assessment under the resolution of the standard commercially available OCT measurement system. In the proposed solution, light backscattered from the evaluated thin layer has been expressed as a multiple beam interference. Therefore, the OCT system was modeled as a two-beam interferometer (e.g., Michelson), in which one beam propagates from the reference arm and the ...

Purpose: The aim of this study was to use swept-source anterior segment optical coherence tomography (OCT) to explore imaging the meibomian gland openings and to identify their in vivo characteristics in patients with obstructive meibomian gland dysfunction (MGD) and healthy participants. Methods: We enrolled 49 patients with MGD and 54 health controls in this case-control study. Each participant underwent slit-lamp examination, meibography, and OCT scanning. Sixteen patients with MGD underwent a repeat OCT examination after eyelid massage. The outcome measures included determinations of meibomian gland openings (orifices and terminal ducts) from OCT images and comparisons of the meibomian openings between ...

The embryonic heart is an active and developing organ. Genetic studies in mouse models have generated great insight into normal heart development and congenital heart defects, and suggest mechanical forces such as heart contraction and blood flow to be implicated in cardiogenesis and disease. To explore this relationship and investigate the interplay between biomechanical forces and cardiac development, live dynamic cardiac imaging is essential.

The aim of this study was to compare retinal thicknesses and vascular parameters between autism spectrum disorder (ASD) and neurotypical (NT) individuals. Recruited ASD subjects and age- and sex-matched NT controls underwent 2 optical coherence tomography scans (OCT) (macular cube and optic nerve cube) and 2 OCT angiography (OCTA) scans (macular and optic nerve head (ONH) OCTA) with the device Cirrus 5000 (Zeiss). Concerning OCT, we considered full retina thickness in 9 macular sectors of the Early Treatment Diabetic Retinopathy Study (ETDRS) pattern and peripapillary retinal nerve fiber layer (pRNFL) thickness in 4 quadrants and 12 clock-hour sectors. Vessel density ...

In this cross-sectional observational study, we investigated the relationship between photoreceptor layer disruption and telangiectasia in patients diagnosed with early stage macular telangiectasia type 2 (MacTel). A total of 31 eyes (17 patients) with MacTel were imaged with adaptive optics scanning laser ophthalmoscopy (AOSLO) and optical coherence tomography angiography (OCTA). Confocal AOSLO was used to visualize dark regions of nonwaveguiding outer segments, which we refer to as “photoreceptor lesions”. En-face OCTA images of the deep capillary plexus (DCP) were used in conjunction with confocal AOSLO to evaluate the topographic relationship between areas of capillary telangiectasias and photoreceptor lesions. Among seven ...

Photoacoustic microscopy is a novel, non-ionizing, non-invasive imaging technology that evaluates tissue absorption of short-pulsed light through the sound waves emitted by the tissue and has numerous biomedical applications. In this study, a custom-built multimodal imaging system, including photoacoustic microscopy (PAM) and optical coherence tomography (OCT), has been developed to evaluate choroidal vascular occlusion (CVO). CVO was performed on three living rabbits using laser photocoagulation. Longitudinal imaging of CVO was obtained using multiple imaging tools such as color fundus photography, fluorescein angiography, indocyanine green angiography (ICGA), OCT, and PAM. PAM images were acquired at different wavelengths, ranging from 532 to ...

Imaging has become indispensable in the diagnosis and management of diseases in the posterior part of the eye. In recent years, imaging techniques for the anterior segment are also gaining importance and are nowadays routinely used in clinical practice. Ocular surface disease is often synonymous with dry eye disease, but also refers to other conditions of the ocular surface, such as Meibomian gland dysfunction or keratitis and conjunctivitis with different underlying causes, i.e., allergies or infections. Therefore, correct differential diagnosis and treatment of ocular surface diseases is crucial, for which imaging can be a helpful tool. A variety of ...

To compare drusen volume between Heidelberg Spectral Domain (SD-) and Zeiss Swept-Source (SS) PlexElite Optical Coherence Tomography (OCT) determined by manual and automated segmentation methods. Thirty-two eyes of 24 patients with Age-Related Macular Degeneration (AMD) and drusen maculopathy were included. In the central 1 and 3 mm ETDRS circle drusen volumes were calculated and compared. Drusen segmentation was performed using automated manufacturer algorithms of the two OCT devices. Then, the automated segmentation was manually corrected and compared and finally analyzed using customized software. Though on SD-OCT, there was a significant difference of mean drusen volume prior to and after manual ...

Purpose: To investigate the associations between early anatomical responses and intraocular pressure (IOP) changes in macular edema (ME) due to retinal vascular diseases treated with an intravitreal dexamethasone (DEX) implant. Methods: A retrospective review was conducted involving ME patients who underwent intravitreal DEX implantation. The eyes were divided into increased IOP (IIOP) or non-IIOP (nIIOP) groups according to the presence or absence of significant IOP elevation. Significant IOP elevation was defined by both the absolute value of IOP elevation (5 mmHg or higher) and an elevation percentage of the baseline IOP (an increase equal to 30% of the pre-injection IOP ...

In this work, we integrated finite element (FE) method and machine learning (ML) method to predict the stent expansion in a calcified coronary artery. The stenting procedure was captured in a patient-specific artery model, reconstructed based on optical coherence tomography images. Following FE simulation, eight geometrical features in each of 120 cross sections in the pre-stenting artery model, as well as the corresponding post-stenting lumen area, were extracted for training and testing the ML models. A linear regression model and a support vector regression (SVR) model with three different kernels (linear, polynomial, and radial basis function kernels) were adopted in ...

Detection of oral dysplastic and early-stage cancerous lesions is difficult with the current tools. Half of oral cancers are diagnosed in a late stage. Detection of early stromal change to predict malignant transformation is a new direction in the diagnosis of early-stage oral cancer. The application of new optical tools to image stroma in vivo is under investigation, and polarization-sensitive optical coherence tomography (PS-OCT) is potentially one of those tools. This is a preliminary study to sequentially image oral stromal changes from normal, hyperplasia, and dysplasia to early-stage cancer by PS-OCT in vivo. We used 4-Nitroquinoline-1-oxide drinking water to induce ...

In this study, four optical techniques—Optical Coherence Tomography, Sidestream Darkfield Microscopy, Laser Speckle Contrast Imaging, and Fluorescence Angiography (FA)—were compared on performing an intraoperative quantitative perfusion assessment of the gastric conduit during oesophagectomy. We hypothesised that the quantitative parameters show decreased perfusion towards the fundus in the gastric conduit and in patients with anastomotic leakage. In a prospective study in patients undergoing oesophagectomy with gastric conduit reconstruction, measurements were taken with all four optical techniques at four locations from the base towards the fundus in the gastric conduit (Loc1, Loc2, Loc3, Loc4). The primary outcome included 14 quantitative ...

Abstract The visual outcome of myopic choroidal neovascularization (CNV) after anti-vascular endothelial growth factor (anti-VEGF) therapy varies among individuals. We retrospectively analyzed the data of 24 eyes (24 patients) with treatment-naïve myopic CNV who underwent anti-VEGF monotherapy following a pro-re-nata regimen at the Division of Medical Retina Clinic, Department of Ophthalmology, Keio University Hospital between May 2014 and December 2017. The mean age was 70.6 ± 2.1 years, and 16 (66.7%) patients were female. Overall, the mean best-corrected visual acuity (BCVA) improved ( p = 0.034), and the mean height of the hyperreflective material (HRM), involving the CNV ...

Central serous chorioretinopathy (CSC) is a complex and not entirely understood retinal disease. The aim of our research was to describe a novel optical coherence tomography (OCT) finding named “choroidal rift”, which may be identified in the choroid of eyes with CSC. We collected data from 357 patients (488 eyes) with CSC who had structural OCT and OCT angiography (OCTA) scans obtained. Choroidal rifts were identified as polygonal (and not round-shaped) hyporeflective lesions without hyperreflective margins. Choroidal rifts had to be characterized by a size superior to that of the largest choroidal vessel. Finally, hyporeflective lesions were graded as choroidal ...

Treatment using light-activated photosensitizers (photodynamic therapy, PDT) has shown limited efficacy in pigmented melanoma, mainly due to the poor penetration of light in this tissue. Here, an optical clearing agent (OCA) was applied topically to a cutaneous melanoma model in mice shortly before PDT to increase the effective treatment depth by reducing the light scattering. This was used together with cellular and vascular-PDT, or a combination of both. The effect on tumor growth was measured by longitudinal ultrasound/photoacoustic imaging in vivo and by immunohistology after sacrifice. In a separate dorsal window chamber tumor model, angiographic optical coherence tomography (OCT ...

A high-speed, high-resolution swept-source optical coherence tomography (SS-OCT) is presented for focusing lens imaging and a k-domain uniform algorithm is adopted to find the wave number phase equalization. The radius of curvature of the laser focusing lens was obtained using a curve-fitting algorithm. The experimental results demonstrate that the measuring accuracy of the proposed SS-OCT system is higher than the laser confocal microscope.

This study aimed to develop and validate a deep learning system for diagnosing glaucoma using optical coherence tomography (OCT). A training set of 1822 eyes (332 control, 1490 glaucoma) with 7288 OCT images, an internal validation set of 425 eyes (104 control, 321 glaucoma) with 1700 images, and an external validation set of 355 eyes (108 control, 247 glaucoma) with 1420 images were included. Deviation and thickness maps of retinal nerve fiber layer (RNFL) and ganglion cell–inner plexiform layer (GCIPL) analyses were used to develop the deep learning system for glaucoma diagnosis based on the visual geometry group deep ...

Fluorescence-guided surgery is a state-of-the-art approach for intraoperative imaging during neurosurgical removal of tumor tissue. While the visualization of high-grade gliomas is reliable, lower grade glioma often lack visible fluorescence signals. Here, we present a hybrid prototype combining visible light optical coherence microscopy (OCM) and high-resolution fluorescence imaging for assessment of brain tumor samples acquired by 5-aminolevulinic acid (5-ALA) fluorescence-guided surgery. OCM provides high-resolution information of the inherent tissue scattering and absorption properties of tissue. We here explore quantitative attenuation coefficients derived from volumetric OCM intensity data and quantitative high-resolution 5-ALA fluorescence as potential biomarkers for tissue malignancy including otherwise ...

Pilling is caused by friction pulling and fuzzing the fibers of a material. Pilling is normally evaluated by visually counting the pills on a flat fabric surface. Here, we propose an objective method of pilling assessment, based on the textural characteristics of the fabric shown in optical coherence tomography (OCT) images. The pilling layer is first identified above the fabric surface. The percentage of protruding fiber pixels and Haralick’s textural features are then used as pilling descriptors. Principal component analysis (PCA) is employed to select strongly correlated features and then reduce the feature space dimensionality. The first principal component ...

ptical coherence tomography (OCT) supports the detection of thickness changes in intraretinal layers at an early stage of diabetes mellitus. However, the analysis of OCT data in cross-sectional studies is complex and time-consuming. We introduce an enhanced deviation map-based analysis (MA) and demonstrate its effectiveness in detecting early changes in intraretinal layer thickness in adults with type 2 diabetes mellitus (T2DM) compared to common early treatment diabetic retinopathy study (ETDRS) grid-based analysis (GA). To this end, we obtained OCT scans of unilateral eyes from 33 T2DM patients without diabetic retinopathy and 40 healthy controls. The patients were categorized according to ...

Background: We sought to investigate visual function, primarily, and structural changes in retinal ganglion cells, secondarily, in patients with major depressive disorder. Methods: A total of 50 normal participants and 49 patients with major depressive disorder were included in this cross-sectional study. The participants underwent 24–2 standard automated perimetry and spectral-domain optical coherence tomography. Results: The pattern standard deviation (PSD) in the visual field test was higher in the major depressive disorder patients than in the normal control subjects ( P = 0.017). The patients with major depressive disorder showed reduced minimum ganglion cell–inner plexiform layer (GCIPL) thickness relative ...