- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Deep structure tensor graph search framework for automated extraction and characterization of retinal layers and fluid pathology in retinal SD-OCT scans
摘要： Maculopathy is a group of retinal disorders that affect macula and cause severe visual impairment if not treated in time. Many computer-aided diagnostic methods have been proposed over the past that automatically detect macular diseases. However, to our best knowledge, no literature is available that provides an end-to-end solution for analyzing healthy and diseased macular pathology. This paper proposes a vendor-independent deep convolutional neural network and structure tensor graph search-based segmentation framework (CNN-STGS) for the extraction and characterization of retinal layers and fluid pathology, along with 3-D retinal profiling. CNN-STGS works by first extracting nine layers from an optical coherence tomography (OCT) scan. Afterward, the extracted layers, combined with a deep CNN model, are used to automatically segment cyst and serous pathology, followed by the autonomous 3-D retinal profiling. CNN-STGS has been validated on publicly available Duke datasets (containing a cumulative of 42,281 scans from 439 subjects) and Armed Forces Institute of Ophthalmology dataset (containing 4,260 OCT scans of 51 subjects), which are acquired through different OCT machinery. The performance of the CNN-STGS framework is validated through the marked annotations, and it significantly outperforms the existing solutions in various metrics. The proposed CNN-STGS framework achieved a mean Dice coefficient of 0.906 for segmenting retinal fluids, along with an accuracy of 98.75% for characterizing cyst and serous fluid from diseased retinal OCT scans.
关键词： convolutional neural network (CNN),Optical coherence tomography (OCT),maculopathy,ophthalmology,graph search
更新于2025-09-23 15:23:52
-
New clinical ultrahigh-resolution SD-OCT using A-scan matching algorithm
摘要： Purpose A new clinical ultrahigh-resolution spectral domain optical coherence tomography (UHR-SD-OCT) system using an original averaging technique named BA-scan matching algorithm^ was developed. The aim of this study was to determine whether our new UHR-SD-OCT system can obtain clearer sectional images of the retina than conventional standard resolution SD-OCT systems (SR-SD-OCT). Methods We recorded horizontal B-scan images of 42 normal eyes using our new UHR-SD-OCT device (Bi-μ, Kowa) and a conventional SR-SD-OCT (Spectralis, Heidelberg). To evaluate the clarity of the interdigitation zone (IZ) subjectively, the integrity of IZ was divided into three types by two raters. To evaluate the clarity of the IZ objectively, a peak height score (PHS) was calculated at five different points of the macula using the longitudinal reflectivity profile. Results The mean (± SD) of the subjective visibility score of the IZ in the UHR-SD-OCT images was 2.64 ± 0.54 which was significantly higher than the 2.46 ± 0.46 in the SR-SD-OCT images (P = 0.02). The PHS was also significantly higher for the UHR-SD-OCT than for the SR-SD-OCT images at all five locations (all P < 0.01). Conclusion The results indicate that the newly developed clinical UHR-SD-OCT instrument using the A-scan matching algorithm can obtain clearer images of the IZ, and they suggest that this device should be clinically useful in detecting finer structural abnormalities of the outer retina.
关键词： Spectral domain,Ultrahigh-resolution,Optical coherence tomography (OCT),Interdigitation zone,Retina
更新于2025-09-23 15:21:21
-
Intra-slice motion correction of intravascular OCT images using deep features
摘要： Intra-slice motion correction is an important step for analyzing volume variations and pathological formations from intravascular imaging. Optical Coherence Tomography (OCT) has been recently introduced for intravascular imaging and assessment of coronary artery disease. 2D cross-sectional OCT images of coronary arteries play a crucial role to characterize the internal structure of the tissues. Adjacent images could be compounded, however they might not fully match due to motion, which is a major hurdle for analyzing longitudinally each tissue in 3D. The aim of this study is to develop a robust tissue matching based motion correction approach from a sequence of 2D intracoronary OCT images. Our motion correction technique is based on the correlation between deep features obtained from Convolutional Neural Network (CNN) for each frame of a sequence. The optimal transformation of each frame is obtained by maximizing the similarity between the tissues of reference and moving frames. The results show a good alignment of the tissues after applying CNN features and determining the transformation parameters.
关键词： Deep Features,Optical Coherence Tomography (OCT),Coronary Artery,Motion Correction,Tissue Characterization
更新于2025-09-23 15:21:01
-
Three-dimensional optical coherence tomography image denoising through multi-input fully-convolutional networks
摘要： In recent years, there has been a growing interest in applying convolutional neural networks (CNNs) to low-level vision tasks such as denoising and super-resolution. Due to the coherent nature of the image formation process, the optical coherence tomography (OCT) images are inevitably affected by noise. This paper proposes a new method named the multi-input fully-convolutional networks (MIFCN) for denoising of OCT images. In contrast to recently proposed natural image denoising CNNs, the proposed architecture allows the exploitation of high degrees of correlation and complementary information among neighboring OCT images through pixel by pixel fusion of multiple FCNs. The parameters of the proposed multi-input architecture are learned by considering the consistency between the overall output and the contribution of each input image. The proposed MIFCN method is compared with the state-of-the-art denoising methods adopted on OCT images of normal and age-related macular degeneration eyes in a quantitative and qualitative manner.
关键词： Multi-input FCN,Optical Coherence Tomography (OCT),Image denoising,Fully convolutional network (FCN)
更新于2025-09-19 17:15:36
-
Optical coherence tomography in imaging of peripheral pulmonary arteries
摘要： Background: To establish an optical coherence tomography (OCT)-based method for imaging peripheral pulmonary arteries. Methods: We recruited eight patients (five men; average age, 48±12 years; peripheral pulmonary artery thrombosis, three patients; idiopathic pulmonary hypertension, three patients; interstitial lung disease, two patients) who underwent OCT of the peripheral pulmonary arteries in the First Affiliated Hospital of Guangzhou Medical University and Guangzhou Institute of Respiratory Diseases, between September 2009 and September 2010. OCT was performed using both the conventional OCT imaging method (COI) and the improved pulmonary artery imaging method (IPI). In the IPI, contrast agent was used as an indicator of balloon inflation meanwhile increases in flushing speed of the replacement fluid. The percentage of optimal images, inflation pressure, flushing speeds and complications were compared between the two methods. Results: We performed OCT of 33 vessel segments by both methods. IPI produced more optimal images than COI (88% vs. 24%). Mean inflation pressure and flushing speed were higher during IPI than COI (0.62±0.15 vs. 0.43±0.08 atm; 1 atm =101.3 kPa; 0.82±0.10 vs. 0.42±0.06 mL/s; both P<0.01). Decreased blood oxygen saturation (SaO2) was associated with 9% and 30% segments (P<0.01) in the COI (mean decrease, 8.4%±3.6%) and IPI groups (mean decrease, 12.1%±5.3%; P<0.05) respectively. SaO2 recovered to pre-imaging levels after oxygen inhalation. Conclusions: IPI is safe and effective for OCT of peripheral pulmonary arteries.
关键词： human body,Optical coherence tomography (OCT),peripheral pulmonary arteries,imaging method
更新于2025-09-19 17:15:36
-
Optical coherence tomography guidance during bioresorbable vascular scaffold implantation
摘要： Bioresorbable vascular scaffold (BRS) represent a revolutionary concept in interventional cardiology. After initial enthusiasm, recent real world registries, including patients with increasing lesion complexity, reported not trivial rates of scaffold thrombosis (ScT). The importance of correct patients selection as well as technical aspects during BRS implantation procedures has been highlighted in several studies suggesting that the high rate of ScT might be related to uncorrected patients/lesions selection together with underutilization of intracoronary imaging guidance leading to suboptimal BRS implantation. The high-resolution power together with the lack of shadowing observed beyond polymer struts makes optical coherence tomography (OCT) the optimal imaging technique to guide BRS implantation and identifies eventually scaffolds failures.
关键词： bioresorbable vascular scaffold (BRS),Optical coherence tomography (OCT)
更新于2025-09-19 17:15:36
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Modeling of the Ultra-Stable Operating Regime in Fourier Domain Mode Locked (FDML) Lasers
摘要： Fourier domain mode locked (FDML) ?ber lasers are broadband wavelength-swept ring systems with record sweep speeds. Lasing is achieved by synchronizing the roundtrip time of the optical ?eld in the ?ber delay cavity with the sweep period of a tunable Fabry-P′erot (FP) bandpass ?lter. Since their invention in 2006, FDML lasers have dramatically enhanced the capabilities of optical coherence tomography (OCT) and various sensing applications. However, the physical coherence limits, such as the maximum achievable coherence length, are yet unknown. An important breakthrough in reaching this limit is a recently experimentally demonstrated highly coherent operation mode over a bandwidth of more than 100 nm [1], referred to as the sweet spot. The sweet spot operation mode is characterized by nearly shot-noise limited ?uctuations in the intensity trace of the laser with signi?cantly enhanced coherence properties, whereas in conventional FDML laser systems the intensity trace is distorted by high frequency noise which negatively affects the coherence length. This ultra-low noise operating regime was generated by an almost perfect compensation of the ?ber dispersion with a manually ?ne tuned chirped ?ber Bragg grating and a highly synchronized sweep rate of the FP ?lter with an accuracy in the range of mHz. Polarization effects were controlled with a polarization maintaining semiconductor optical ampli?er (SOA) gain medium and a polarization controller.
关键词： Fourier domain mode locked (FDML) lasers,sweet spot operation mode,coherence length,semiconductor optical amplifier (SOA),polarization controller,optical coherence tomography (OCT)
更新于2025-09-11 14:15:04
-
Intravital imaging of adriamycin-induced renal pathology using two-photon microscopy and optical coherence tomography
摘要： Adriamycin (doxorubicin), a common cancer chemotherapeutic drug, can be used to induce a model of chronic progressive glomerular disease in rodents. In our studies, we evaluated renal changes in a rat model after Adriamycin injection using two-photon microscopy (TPM), optical coherence tomography (OCT) and Doppler OCT (DOCT). Taking advantage of deep penetration and fast scanning speed for three-dimensional (3D) label-free imaging, OCT/DOCT system was able to reveal glomerular and tubular pathology noninvasively and in real time. By imaging renal pathology following the infusion of °uorophore-labeled dextrans of di?erent molecular weights, TPM can provide direct views of glomerular and tubular °ow dynamics with the onset and progression of renal disease. Speciˉcally, glomerular permeability and ˉltration, proximal and distal tubular °ow dynamics can be revealed. 6–8 weeks after injection of Adriamycin, TPM and OCT/DOCT imaging revealed glomerular sclerosis, compromised °ow across the glomerular wall, tubular atrophy, tubular dilation, and variable intra-tubular °ow dynamics. Our results indicate that TPM and OCT/DOCT provide real-time imaging of renal pathology in vivo that has not been previously available using conventional microscopic procedures.
关键词： Two-photon Microscopy (TPM),Chronic kidney disease (CKD),Tubular Atrophy,glomerulosclerosis,Optical Coherence Tomography (OCT)
更新于2025-09-11 14:15:04
-
Sequential phases of RGC axonal and somatic injury in EAE mice examined using DTI and OCT
摘要： Background: Clinical imaging modalities including optical coherence tomography (OCT) and di?usion tensor imaging (DTI) are vital in Multiple Sclerosis (MS), but their relationships during the di?erent phases of Retinal ganglion cell (RGC) degeneration are not clear. We hypothesize that initial injury in optic nerve causes axonal degeneration leading to RGC loss in retina, which can be characterized by a combination of DTI and OCT. Our objective was to examine the correlation between noninvasive and histological data to chronicle the degeneration pro?le of RGCs in the retina and optic nerve in a mouse model of MS. Materials and methods: Experimental Autoimmune Encephalomyelitis (EAE) was induced in 11 C57Bl/6 mice, with 8 mice reserved as controls. OCT and DTI was conducted 2–8 weeks after induction of EAE. The thickness of the retinal ganglion cell complex (GCC) was measured using OCT and compared to DTI indices measured in optic nerves. End-stage histology was used to quantify axon/myelin loss in the optic nerve and retinal thinning/RGC loss in the retina. Results: Signi?cant changes in DTI-derived Axial Di?usivity (AD, ?17.2%) and Trace Di?usivity (TR, ?18.3%) began after 2 weeks of EAE. Later signi?cant reductions in Fractional Anisotropy (FA) and AD, with increases in Radial Di?usion (RD) were apparent after 4 and 8 weeks. OCT-derived measures of GCC thickness were reduced after 4 weeks, and reached signi?cant reduction after 8 weeks. Among EAE mice, DTI (FA, AD and RD measures) and OCT measures were all signi?cantly correlated after 4 and 8 weeks. Among histology measures, RGC density (?23%), RGC size (?27%), and the number of SMI31+ axons (?54%) were reduced signi?cantly. DTI measures of FA and AD along with GCC thinning were the best independent predictors of axon loss. Conclusions: DTI and OCT measures are tightly correlated during the chronic phase of axonal degeneration (4–8 weeks) in EAE mice. After 8 weeks of EAE, both OCT and DTI measures are strong predictors of axon loss in the Optic Nerve.
关键词： longitudinal study,Optical coherence tomography (OCT),Retinal ganglion cell (RGC),Experimental Autoimmune Encephalomyelitis (EAE),Di?usion tensor imaging (DTI)
更新于2025-09-10 09:29:36
-
Repeatability, reproducibility and interocular difference in the assessments of optic nerve OCT in children– a Swedish population-based study
摘要： Background: The aim was, first, to collect normative data of the optic nerve head and the peripapillary retinal nerve fibre layer (RNFL) thickness assessed with Cirrus SD-OCT, in healthy children in a population-based study; second, using these data, to examine repeatability, reproducibility and the interocular difference. Methods: One-hundred and ten eyes from 57 children aged 6–15 born at term, were examined. Best-corrected visual acuity and refraction were assessed. Both eyes were examined and the interocular difference was calculated. Repeatability was calculated by one examiner performing three assessments. Thereafter, a second examiner repeated the assessments to calculate reproducibility. Results: Mean RNFL thickness was 99.2 (SD 8.8) μm, mean disc area 1.89 (SD 0.37) mm2 and mean rim area 1.52 (SD 0.26) mm2. No significant correlations with age, gender or refraction were found. Repeatability and reproducibility were good overall. There was interocular symmetry between the eyes. Conclusions: Normal values for optic nerve head and RNFL thickness assessed with Cirrus SD-OCT were gathered to obtain a normal material in children. High repeatability and reproducibility indicated reliability of assessments performed by different examiners on different occasions. Overall, good correlation between right and left eyes was found.
关键词： Children,Optical coherence tomography (OCT),Repeatability,Interocular difference,Normal values,Reproducibility
更新于2025-09-10 09:29:36