Journal articles: 'Blood-vessels Tomography'

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Stojanovich, L., and A. Djokovic. "Tomography and blood vessels in Hughes syndrome." Lupus 23, no. 4 (January 16, 2014): 337–41. http://dx.doi.org/10.1177/0961203313520061.

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GUIMARAES, P., P. RODRIGUES, R. BERNARDES, and P. SERRANHO. "3D blood vessels segmentation from optical coherence tomography." Acta Ophthalmologica 90 (August 6, 2012): 0. http://dx.doi.org/10.1111/j.1755-3768.2012.2712.x.

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Proskurin, S. G., and S. V. Frolov. "Visualization of Blood Vessels Using Optical Coherence Tomography." Biomedical Engineering 46, no. 3 (August 31, 2012): 96–99. http://dx.doi.org/10.1007/s10527-012-9276-7.

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Martinsen, Ørjan G., Håvard Kalvøy, Sverre Grimnes, Bernt Nordbotten, Per Kristian Hol, Erik Fosse, Helge Myklebust, and Lance B. Becker. "Invasive Electrical Impedance Tomography for Blood Vessel Detection." Open Biomedical Engineering Journal 4, no. 1 (July 9, 2010): 135–37. http://dx.doi.org/10.2174/1874120701004010135.

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We present a novel method for localization of large blood vessels using a bioimpedance based needle positioning system on an array of ten monopolar needle electrodes. The purpose of the study is to develop a portable, low cost tool for rapid vascular access for cooling and controlled reperfusion of cardiac arrest patients. Preliminary results show that localization of blood vessels is feasible with this method, but larger studies are necessary to improve the technology.

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Gladish, James C., Gang Yao, Nicolas L? Heureux, and Mark A. Haidekker. "Optical Transillumination Tomography for Imaging of Tissue-Engineered Blood Vessels." Annals of Biomedical Engineering 33, no. 3 (January 2005): 323–27. http://dx.doi.org/10.1007/s10439-005-1734-x.

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Ramakonar, Hari, Bryden C. Quirk, Rodney W. Kirk, Jiawen Li, Angela Jacques, Christopher R. P. Lind, and Robert A. McLaughlin. "Intraoperative detection of blood vessels with an imaging needle during neurosurgery in humans." Science Advances 4, no. 12 (December 2018): eaav4992. http://dx.doi.org/10.1126/sciadv.aav4992.

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Intracranial hemorrhage can be a devastating complication associated with needle biopsies of the brain. Hemorrhage can occur to vessels located adjacent to the biopsy needle as tissue is aspirated into the needle and removed. No intraoperative technology exists to reliably identify blood vessels that are at risk of damage. To address this problem, we developed an “imaging needle” that can visualize nearby blood vessels in real time. The imaging needle contains a miniaturized optical coherence tomography probe that allows differentiation of blood flow and tissue. In 11 patients, we were able to intraoperatively detect blood vessels (diameter, >500 μm) with a sensitivity of 91.2% and a specificity of 97.7%. This is the first reported use of an optical coherence tomography needle probe in human brain in vivo. These results suggest that imaging needles may serve as a valuable tool in a range of neurosurgical needle interventions.

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Diaz, J. Daniel, Jay C. Wang, Patrick Oellers, Inês Lains, Lucia Sobrin, Deeba Husain, Joan W. Miller, Demetrios G. Vavvas, and John B. Miller. "Imaging the Deep Choroidal Vasculature Using Spectral Domain and Swept Source Optical Coherence Tomography Angiography." Journal of VitreoRetinal Diseases 2, no. 3 (April 16, 2018): 146–54. http://dx.doi.org/10.1177/2474126418771805.

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Purpose: To evaluate the deeper choroidal vasculature in eyes with various ocular disorders using spectral domain (SD) optical coherence tomography angiography (OCTA) and swept source (SS) OCTA. Methods: Patients underwent OCTA imaging with either SD-OCTA (Zeiss Cirrus Angioplex or Optovue AngioVue) or SS-OCTA (Topcon Triton). Retinal pigment epithelium (RPE) integrity, structural visualization of deep choroidal vessels on en face imaging, and OCTA of deep choroidal blood flow signal were analyzed. Choroidal blood flow was deemed present if deeper choroidal vessels appeared bright after appropriate segmentation. Results: Structural visualization of choroidal vessels was feasible in all eyes by en face imaging. In both SD-OCTA and SS-OCTA, choroidal blood flow signal was present in all eyes with overlying RPE atrophy (100% of eyes with RPE atrophy, 28.6% of all imaged eyes, P < .001). Conclusions: While choroidal vessels can be visualized anatomically in all eyes by en face imaging, choroidal blood flow detection in deep choroidal vessel is largely restricted to areas with overlying RPE atrophy. Intact RPE acts as a barrier for reliable detection of choroidal flow using current OCTA technology, inhibiting evaluation of flow in deeper choroidal vessels in most eyes.

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Liu, Jingxuan, Jinyu Fan, Quan Wang, Wen He, Caihua Dong, Minxuan Sun, and Guohua Shi. "Observation of the early blood vessels of cutaneous malignant melanoma using Swept Source Optical Coherence Tomography Angiography (SS-OCTA)." Journal of Innovative Optical Health Sciences 12, no. 04 (July 2019): 1942005. http://dx.doi.org/10.1142/s1793545819420057.

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Melanoma, characterized by high mortality, rapid development and accompanied with angiogenesis is the most typical malignant tumor in skin cancer. Hence, the detection of blood vessels is of much significance. The early vascular network has small scale. If we remove the tumor early and biopsy it, it will increase the spread of the cancer cells and infection and bleeding. In this case, we presented a new angiography method. A high-resolution OCT system for noninvasive angiographic imaging of early skin melanoma — Swept Source Optical Coherence Tomography Angiography (SS-OCTA) is proposed. With a high lateral resolution of 10[Formula: see text][Formula: see text]m in vivo tomographic angiography, SS-OCTA is used to image and identify the morphology of the early tumor blood vessels. In addition, a control group experiment is conducted to observe the growth of melanoma in the process of rupture, malformation of micro-vessels. The results of the analysis and statistical test ([Formula: see text]) are statistically significant.

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Wang, Li, Di Ke, Haishu Xin, Rui Liu, Shu Pan, Kedi Xiong, and Sihua Yang. "Optical-visualized photoacoustic tomographic navigation." Applied Physics Letters 122, no. 2 (January 9, 2023): 023701. http://dx.doi.org/10.1063/5.0135655.

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The current preoperative vascular imaging methods cannot achieve noninvasive high-resolution imaging of deep-localized vessels. Photoacoustic tomography (PAT) can show microvessels with centimeter depth and submillimeter diameter without the use of contrast agents. Combined with PAT and optical projection technology, the Hessian-matrix-based skin removal algorithm and the target matching method were developed to spatially align the photoacoustic data of subcutaneous blood vessels with the anatomy of real patients and to realize three-dimensional (3D) visualization of blood vessels from the body surface. The optical projection navigation system based on PAT has high spatial resolution (∼135 μm) and temporal resolution (0.1 s). In the rabbit injection experiment, 3D distributions of needle and blood vessel (>100 μm) were obtained by image segmentation, which proved that the method can guide micro plastic injection. Furthermore, healthy volunteers' forehead imaging experiments show that 3D visualization and cross-sectional images of the human forehead clearly show the vascular network and ability of the system to image submillimeter blood vessels with penetration depth (∼10.2 mm). Our work confirms that the method of integrated photoacoustic imaging and optical projection has great potential for noninvasive diagnosis and treatment of clinical blood vessels, opening a path for the application of photonics in medical esthetics.

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Nelson, J. S., T. E. Milner, B. S. Tanenbaum, D. M. Goodman, and M. J. C. Van Gemert. "Infra-red tomography of port-wine-stain blood vessels in human skin." Lasers in Medical Science 11, no. 3 (September 1996): 199–204. http://dx.doi.org/10.1007/bf02156765.

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Yao, Gang, and Mark A. Haidekker. "Transillumination optical tomography of tissue-engineered blood vessels: a Monte Carlo simulation." Applied Optics 44, no. 20 (July 10, 2005): 4265. http://dx.doi.org/10.1364/ao.44.004265.

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Yang, Shaozhuang, Liwei Liu, Yixin Chang, Ningning Zhang, Kun Liu, Liang Hong, Bingling Chen, Yue Zhao, Rui Hu, and Junle Qu. "In vivo mice brain microcirculation monitoring based on contrast-enhanced SD-OCT." Journal of Innovative Optical Health Sciences 12, no. 01 (January 2019): 1950001. http://dx.doi.org/10.1142/s1793545819500019.

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In this paper, we proposed a contrast-enhanced homemade spectral domain optical coherence tomography (SD-OCT) method for monitoring of brain microcirculation. We used the polyethylene glycol (PEG)-ylated gold nanorods (GNRs) as a contrast-enhanced agent, obtained clearly 2D and 3D OCT images of blood vessels and dynamic changes of probes in mouse blood vessels. Owing to high scattering of the PEG-GNRs, more tiny blood vessels can be imaged and the OCT signal can be enhanced by 5.87 dB after injection of PEG-GNRs for 20[Formula: see text]min, the enhancement then declined gradually for 60[Formula: see text]min. Our results demonstrate an effective technique for the enhanced imaging of blood vessels in vivo, especially for studies of the brain microcirculation, which could be serviced for disease mechanism research and therapeutic drug monitoring.

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Ramakonar, Hari H. "220 A Stereotactic Brain Biopsy Needle Integrating an Optical Coherence Tomography (OCT) Probe with Blood Vessel Detection in Human Patients." Neurosurgery 64, CN_suppl_1 (August 24, 2017): 260. http://dx.doi.org/10.1093/neuros/nyx417.220.

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Abstract INTRODUCTION Stereotactic brain biopsies are a common neurosurgical procedure used predominantly to obtain histological diagnosis of brain pathologies. Intracranial haemorrhage is the most frequent complication related to this procedure and is associated with increased morbidity and mortality. We present a pilot study investigating a customised miniature Optical Coherence Tomography (OCT) probe integrated into a commercial stereotactic brain biopsy needle. OCT is a high-resolution optical imaging modality that uses reflections of low-power, near-infrared light to characterise tissue. The probe is combined with fully automated blood vessel detection software based on speckle decorrelation to provide real-time feedback as the needle tip encounters a blood vessel. METHODS We demonstrate the use of such a needle intraoperatively for the first time in humans. A total of 167 superficial blood vessel and control measurements were obtained in 11 patients undergoing craniotomies for various pathologies. Deep blood vessel measurements were also acquired in 3 patients. Superficial blood vessel measurements were obtained by directly placing the probe over cortical vessels exposed during craniotomy and validated against intraoperative photographs. Deep vessels were targeted using preoperative MRI and frameless stereotactic surgical navigation. RESULTS >For the superficial vessel measurements, the probe demonstrated a sensitivity of >88% and specificity >98% for the detection of blood vessels >500microns in diameter. For the deep vessel measurements, the probe was able to detect a blood vessel appropriately on all three occasions. CONCLUSION This pioneering study demonstrates OCT detection of blood vessels in human patients in real-time, integrated with current Neurosurgical practices. This work opens the possibilities of further studies using OCT to detect blood vessels in probe based Neurosurgery to minimise the risk of haemorrhage from such procedures.

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Matveev, Lev, Elena Kiseleva, Mikhail Baleev, Alexander Moiseev, Maxim Ryabkov, Arseniy Potapov, Evgeniya Bederina, et al. "Optical Coherence Tomography Angiography and Attenuation Imaging for Label-Free Observation of Functional Changes in the Intestine after Sympathectomy: A Pilot Study." Photonics 9, no. 5 (April 29, 2022): 304. http://dx.doi.org/10.3390/photonics9050304.

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We present in this study optical coherence tomography angiography (OCTA) and OCT attenuation imaging (OCTAI) for in vivo non-destructive visualization of intramural blood and lymphatic vessels of the intestine wall. Rabbit small intestine in the norm and after thoracolumbar sympathectomy served as the object of the intraoperative study. Compared to OCTA real-time imaging, OCTAI takes several minutes and can be termed as “nearly real time”. OCTAI signal processing was modified to take into account the signal-to-noise ratio and the final thickness of the intestine wall. The results showed that, after sympathectomy, changes in functioning of intramural blood and lymphatic vessels were observed with a high statistical significance. The occurrence of trauma-induced constriction of the blood and lymphatic vessels led to an especially pronounced decrease in the length of small-caliber (<30 µm) blood vessels (p < 10−5), as well as in the volumetric density of lymphatic vessels (on average by ~50%) compared to their initial state. Remarkably, OCTA/OCTAI modalities provide the unique ability for “nearly-instant detection” of changes in functional status of the tissues, long before they become visible on histology. The proposed approach can be used in further experiments to clarify the mechanisms of changes in intestinal blood and lymph flows in response to trauma of the nervous system. Furthermore, potentially it can be used intraoperatively in patients requiring express diagnosis of the state of intramural blood and lymph circulation.

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Pilch, Matthäus, Yaroslava Wenner, Elisabeth Strohmayr, Markus Preising, Christoph Friedburg, Erdmuthe Meyer zu Bexten, Birgit Lorenz, and Knut Stieger. "Automated segmentation of retinal blood vessels in spectral domain optical coherence tomography scans." Biomedical Optics Express 3, no. 7 (June 4, 2012): 1478. http://dx.doi.org/10.1364/boe.3.001478.

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Bonesi, M., S. G. Proskurin, and I. V. Meglinski. "Imaging of subcutaneous blood vessels and flow velocity profiles by optical coherence tomography." Laser Physics 20, no. 4 (March 10, 2010): 891–99. http://dx.doi.org/10.1134/s1054660x10070029.

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Maruko, Ichiro, Hideki Koizumi, Shota Sawaguchi, Taiji Hasegawa, Hisaya Arakawa, and Tomohiro Iida. "CHOROIDAL BLOOD VESSELS IN RETINAL PIGMENT EPITHELIAL ATROPHY USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY." Retinal Cases & Brief Reports 13, no. 1 (2019): 88–93. http://dx.doi.org/10.1097/icb.0000000000000542.

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Sirotkina, M. A., A. L. Potapov, N. N. Vagapova, I. K. Safonov, D. A. Karashtin, L. A. Matveev, S. G. Radenska-Lopovok, et al. "Multimodal Optical Coherence Tomography: Imaging of Blood and Lymphatic Vessels of the Vulva." Sovremennye tehnologii v medicine 11, no. 4 (December 2019): 26. http://dx.doi.org/10.17691/stm2019.11.4.03.

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Ulrich, M., L. Themstrup, N. de Carvalho, S. Ciardo, J. Holmes, R. Whitehead, J. Welzel, G. B. E. Jemec, and G. Pellacani. "Dynamic optical coherence tomography of skin blood vessels - proposed terminology and practical guidelines." Journal of the European Academy of Dermatology and Venereology 32, no. 1 (August 29, 2017): 152–55. http://dx.doi.org/10.1111/jdv.14508.

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S., Pearl Mary, and Thanikaiselvan V. "Unified adaptive framework for contrast enhancement of blood vessels." International Journal of Electrical and Computer Engineering (IJECE) 10, no. 1 (February 1, 2020): 767. http://dx.doi.org/10.11591/ijece.v10i1.pp767-777.

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Information about blood vessel structures influences a lot of diseases in the medical realm. Therefore, for proper localization of blood vessels, its contrast should be enhanced properly. Since the blood vessels from all the medical angio-images have almost similar properties, a unified approach for the contrast enhancement of blood vessel structures is very useful. This paper aims to enhance the contrast of the blood vessels as well as the overall contrast of all the medical angio-images. In the proposed method, initially, the vessel probability map is extracted using hessian eigenanalysis. From the map, vessel edges and textures are derived and summed at every pixel location to frame a unique fractional differential function. The resulting fractional value from the function gives out the most optimal fractional order that can be adjusted to improve the contrast of blood vessels by convolving the image using Grunwald-Letnikov (G-L) fractional differential kernel. The vessel enhanced image is Gaussian fitted and contrast stretched to get overall contrast enhancement. This method of enhancement, when applied to medical angio-images such as the retinal fundus, Computerised Tomography (CT), Coronary Angiography (CA) and Digital Subtraction Angiography (DSA), has shown improved performance validated by the performance metrics.

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Yang, Shaozhuang, Haobin Chen, Liwei Liu, Bingling Chen, Zhigang Yang, Changfeng Wu, Siyi Hu, Huiyun Lin, Buhong Li, and Junle Qu. "OCT imaging detection of brain blood vessels in mouse, based on semiconducting polymer nanoparticles." Analyst 142, no. 23 (2017): 4503–10. http://dx.doi.org/10.1039/c7an01245d.

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Optical Coherence Tomography (OCT) is a valuable technology that has been used to obtain microstructure images of tissue, and has several advantages, though its applications are limited in high-scattering tissues.

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Borisenko, V. V., N. S. Serova, and A. M. Chepovskiy. "Reconstruction of Three-Dimensional Geometry of the Vessels by Computed Tomography Data." Vestnik NSU. Series: Information Technologies 17, no. 3 (2019): 5–17. http://dx.doi.org/10.25205/1818-7900-2019-17-3-5-17.

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We consider algorithms of 3D reconstruction for the internal surface of cardiac vessels. The precise reconstruction of vessel geometry is necessary for the creating a hydrodynamic model of blood supply for the heart and computing various parameters of blood flow. To compute a triangulation of blood vessel walls, we use the combination of two methods. At the first stage we apply the 3D seeded region growing algorithm to reconstruct a set of voxels inside vessels. At the second stage we use the isosurface reconstruction algorithm based on the tessellation of 3D space into small tetrahedral cells. We use the tetrahedral mesh, which was proposed in the works of S. Chan, E. Purisima (1998), and V. Skala (2000). Tetrahedra in this mesh are constructed on common faces of adjacent cubes in a cubic lattice, so it fits well with the voxel model. The mesh is constructed only in the neighborhood of the border of voxel set obtained at the first stage as the result of seeded region growing algorithms.

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An, Weiting, and Jindong Han. "Research progress of UWFFA and OCTA in retinal vein occlusion: A review." European Journal of Ophthalmology 31, no. 6 (November 2021): 2850–55. http://dx.doi.org/10.1177/11206721211027411.

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Retinal vein occlusion (RVO) is a retinal vascular disease that severely impairs the visual function of patients. Observing the changes of retinal blood vessels before and after treatment is of great significance for the prognostic evaluation of RVO. The rapid development and widespread use of fundus imaging technique, especially ultra-wide-angle fundus fluorescein angiography (UWFFA) and optical coherence tomography angiography (OCTA) have made our observation of the retinal blood vessels of RVO more comprehensive and meticulous. In this paper, we reviewed the latest research progress of UWFFA and OCTA in RVO.

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Pellegrini, Marco, Aldo Vagge, Lorenzo Ferro Desideri, Federico Bernabei, Giacinto Triolo, Rodolfo Mastropasqua, Chiara Del Noce, et al. "Optical Coherence Tomography Angiography in Neurodegenerative Disorders." Journal of Clinical Medicine 9, no. 6 (June 2, 2020): 1706. http://dx.doi.org/10.3390/jcm9061706.

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Retinal microcirculation shares similar features with cerebral small blood vessels. Thus, the retina may be considered an accessible ‘window’ to detect the microvascular damage occurring in the setting of neurodegenerative disorders. Optical coherence tomography angiography (OCT-A) is a non-invasive imaging modality providing depth resolved images of blood flow in the retina, choroid, and optic nerve. In this review, we summarize the current literature on the application of OCT-A in glaucoma and central nervous system conditions such as Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis. Future directions aiming at evaluating whether OCT-A can be an additional biomarker for the early diagnosis and monitoring of neurodegenerative disorders are also discussed.

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Pulatova, I. Z., and M. A. Isamukhamedova. "The role of doppler ultrasound and multislice spiral computed tomography angiography in the common form of stomach cancer diagnosis." Kazan medical journal 97, no. 1 (February 15, 2016): 59–65. http://dx.doi.org/10.17750/kmj2016-59.

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Aim. To evaluate the results of Doppler ultrasound and multislice computed tomography angiography in patients with gastric cancer and the sensitivity of these diagnostic methods for the detection of the abdomen great vessels lesions.Methods. The study included 32 patients aged 37 to 82 years who had histologically confirmed gastric adenocarcinoma diagnosis. The control group consisted of 30 apparently healthy people of the same age. Transabdominal ultrasonography of the abdominal cavity organs and stomach in gray-scale mode (B-mode before and after the stomach filling with degassed liquid), Doppler ultrasound of the abdomen and the stomach wall vessels, multislice spiral computed tomography angiography were performed in all patients at the preoperative stage. The analysis of the study results and their comparison with intraoperative data were conducted.Results. In patients with gastric cancer a statistically significant increase in peak systolic velocity in the celiac trunk, superior mesenteric artery, left gastric artery and resistive index decrease in these blood vessels (p <0.05) with the presence of atypical vascularization in the affected stomach walls were registered. The data obtained during the multislice spiral computed tomography angiography were analyzed. The sensitivity of Doppler ultrasound in the preoperative detection of abdominal cavity great vessels affection in patients with gastric cancer was 77.8%, multislice spiral computed tomography angiography - 88.9%, the combination of these two methods - 96.3%.Conclusion. The analysis of used diagnostic methods of examination of patients with stomach cancer showed that Doppler ultrasound should be included in the patients examination standard to assess the abdominal cavity great vessels condition, what is important in deciding on the possibility of operative intervention; the sensitivity of the combination of dopplerography and multislice spiral computed tomography angiography in the diagnosis of great vessels affection is 96.3%.

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Silver, Frederick H., Tanmay Deshmukh, Nicole Ryan, Arielle Romm, and Hari Nadiminti. "“Fingerprinting” Benign and Cancerous Skin Lesions Using Vibrational Optical Coherence Tomography: Differentiation among Cancerous Lesion Types Based on the Presence of New Cells, Blood Vessels, and Fibrosis." Biomolecules 12, no. 10 (September 21, 2022): 1332. http://dx.doi.org/10.3390/biom12101332.

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In this study, we use vibrational optical coherence tomography (VOCT) to examine the morphology and stiffness of benign and cancerous lesions. Lesion images and 3D plots of weighted displacement versus frequency and depth were used to compare the cellular, dermal collagen, new blood vessels, and fibrotic composition of normal skin, actinic keratoses (AK), nodular and superficial basal cell carcinomas (BCCs), squamous cell carcinomas (SCCs), and melanomas. The results of this study suggest that benign and cancerous lesions differ based on the addition of new cells with increased resonant frequency and stiffness (80Hz, 1.8MPa), new blood vessel peaks (130Hz, 4.10MPa) that appear to be less stiff than normal blood vessels, and new fibrous tissue peaks (260Hz, 15–17 MPa) that are present in carcinomas but not in normal skin and only partially present (80Hz and 130Hz only) in AKs. Results obtained by creating images based on the location of the 80Hz, 130Hz, and 260Hz peaks of cancerous skin lesions suggest that the fibrous tissue appears to surround the new cells and new lesion blood vessels. The results of this study suggest that the morphology and location of the fibrous tissues in relation to the new cancer-associated cells and lesion blood vessels may provide information on the invasiveness and metastatic potential of skin cancers. The invasiveness and metastatic potential of melanomas may be a result of the cancer-associated cells laying down fibrous tissue that is used as a pathway for migration. The new cancer-associated blood vessels in the vicinity of the new cancer-associated cells may promote this migration and eventual metastasis. The ratios of peak heights 50/130Hz and 80/130Hz of normal cells, new lesion cells, new lesion blood vessels, and fibrotic tissue may be used as a “fingerprint” for detecting melanoma and to differentiate it from other skin cancers non-invasively using VOCT.

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Cano, Jennifer, Shayan Farzad, Maziyar M. Khansari, Ou Tan, David Huang, Jennifer I. Lim, and Mahnaz Shahidi. "Relating retinal blood flow and vessel morphology in sickle cell retinopathy." Eye 34, no. 5 (September 26, 2019): 886–91. http://dx.doi.org/10.1038/s41433-019-0604-y.

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Abstract Purpose The purpose of the current study was to determine associations between retinal blood flow and vessel morphology metrics in sickle cell retinopathy (SCR) and healthy normal control (NC) subjects. Methods Optical coherence tomography angiography (OCTA) and Doppler OCT imaging were performed in 12 SCR (15 eyes) and 19 NC (26 eyes) subjects. Vessel tortuosity was measured using a dedicated image analysis algorithm applied to OCTA images. Vessel density and spacing between vessels were determined from OCTA images by a fractal dimension analysis method. Retinal blood flow was quantified using a phase-resolved technique applied to en face Doppler OCT images. Results There was a significant association between increased retinal blood flow and increased vessel tortuosity (P = 0.03). Furthermore, increased retinal blood flow was associated with increased vessel density (P = 0.03) and decreased spacing between small vessels (P = 0.01). There was no significant association between retinal blood flow and spacing between large vessels (P = 0.11). Vessel tortuosity and blood flow were increased, whereas spacing between small vessels was decreased in SCR compared to NC group (P ≤ 0.03). There were no significant differences in vessel density or spacing between large vessels between the SCR and NC groups (P ≥ 0.31). Conclusions Associations between retinal hemodynamics and vessel morphology were reported, providing better understanding of retinal pathophysiology and insight into potential quantitative biomarkers to evaluate SCR.

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Ehling, Josef, Twan Lammers, and Fabian Kiessling. "Non-invasive imaging for studying anti-angiogenic therapy effects." Thrombosis and Haemostasis 109, no. 03 (2013): 375–90. http://dx.doi.org/10.1160/th12-10-0721.

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SummaryNoninvasive imaging plays an emerging role in preclinical and clinical cancer research and has high potential to improve clinical translation of new drugs. This article summarises and discusses tools and methods to image tumour angiogenesis and monitor anti-angiogenic therapy effects. In this context, micro-computed tomography (?CT) is recommended to visualise and quantify the micro-architecture of functional tumour vessels. Contrast-enhanced ultrasound (US) and magnetic resonance imaging (MRI) are favourable tools to assess functional vascular parameters, such as perfusion and relative blood volume. These functional parameters have been shown to indicate antiangiogenic therapy response at an early stage, before changes in tumour size appear. For tumour characterisation, the imaging of the molecular characteristics of tumour blood vessels, such as receptor expression, might have an even higher diagnostic potential and has been shown to be highly suitable for therapy monitoring as well. In this context, US using targeted microbubbles is currently evaluated in clinical trials as an important tool for the molecular characterisation of the angiogenic endothelium. Other modalities, being preferably used for molecular imaging of vessels and their surrounding stroma, are photoacoustic imaging (PAI), near-infrared fluorescence optical imaging (OI), MRI, positron emission tomography (PET) and single photon emission computed tomography (SPECT). The latter two are particularly useful if very high sensitivity is needed, and/or if the molecular target is difficult to access. Carefully considering the pros and cons of different imaging modalities in a multimodal imaging setup enables a comprehensive longitudinal assessment of the (micro)morphology, function and molecular regulation of tumour vessels.

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Hua, Rui, and Hailin Wang. "Dark Signals in the Choroidal Vasculature on Optical Coherence Tomography Angiography: An Artefact or Not?" Journal of Ophthalmology 2017 (2017): 1–8. http://dx.doi.org/10.1155/2017/5498125.

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Optical coherence tomography angiography (OCTA) based on mathematical processing of sequentially acquired structural OCT images has been applied widely in both retinal and choroidal research and may have advantages over traditional angiography. Images obtained by OCTA are rendered under the assumption that the only moving entity in the retina is blood flow. Optical phenomena and image processing algorithms may create imaging artefacts. Therefore, OCTA images require careful interpretation. This review discusses the dark signals seen in the choroidal vasculature on OCTA using multiple factor analysis. For accurate and comprehensive interpretation of the choroidal vasculature, we recommend simultaneous consideration of the laser light penetration depth and masking effect of retinal pigment epithelium, the orientation of vessels in relation to the scanning lasers and blood flow, the range of regional detectable velocity of blood flow, atrophic tissues in the periphery, and absorption of superior vessels on the scanning laser.

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Yang, Shanshan, Kezhou Liu, Huijie Ding, Huan Gao, Xiaoxiang Zheng, Zhihua Ding, Kedi Xu, and Peng Li. "Longitudinal in vivo intrinsic optical imaging of cortical blood perfusion and tissue damage in focal photothrombosis stroke model." Journal of Cerebral Blood Flow & Metabolism 39, no. 7 (March 9, 2018): 1381–93. http://dx.doi.org/10.1177/0271678x18762636.

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A thorough understanding of the spatiotemporal dynamics of blood supply and tissue viability is of great importance in stroke researches. In the current study, vascular and cellular responses to focal ischemia were monitored with optical coherence tomography on chronic rat photothrombotic stroke model. The 3D mapping of blood perfusion and cellular scattering were achieved by analyzing the temporal dynamics and depth attenuation of intrinsic backscattered light respectively. Optical coherence tomography revealed that vessels of different types presented various spatial and temporal dynamics during the photothrombotic occlusion and the later recovery period. The large distal middle cerebral arteries presented a spontaneous recanalization and the small pial microvessels presented a reperfusion along with newly appeared vessels from the peripheral into the core area. The cortical capillary perfusion presented a weak recovery. Compared to the male group, the female rats showed a faster vascular recovery after photothrombotic. Moreover, the dynamic changes of the cellular scattering signal showed a high spatial and temporal correlation with the cortical capillary perfusion. Combined with well-designed photothrombotic stroke model and chronic optical window, optical coherence tomography imaging offers a unique approach to improve the understanding of stroke procedure and evaluate the treatment outcomes.

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Nikolic, Igor, Goran Tasic, Vladimir Jovanovic, Nikola Repac, Aleksandar Janicijevic, Vuk Scepanovic, and Branislav Nestorovic. "Assessing the quality of angiographic display of brain blood vessels aneurysms compared to intraoperative state." Vojnosanitetski pregled 70, no. 12 (2013): 1117–23. http://dx.doi.org/10.2298/vsp1312117n.

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Background/Aim. Aneurysms in brain blood vessels are expanding bags composed of a neck, body and fundus. Clear visibility of the neck, the position of the aneurysm and surrounding structures are necessary for a proper choice of methods for excluding the aneurysm from the circulation. The aim of this study was to evaluate the reliability of spatial reconstruction of blood vessels of the brain based on the original software for 3D reconstruction of the equipment manufacturer and a personal computer model developed earlier in the Clinic for Neurosurgery, Clinical Center of Serbia, Belgrade, compared to intraoperative identification of these aneurysms. Methods. This study included 137 patients of both sexes. The presence of an aneurysm was verified by angiographic methods [computed tomographic angiography (CTA), multislice computed tomography angiography (MSCTA), magnetic resonance imaging angiography (MRA), or digital subtraction angiography (DSA)]. Results. The quality score (0 to 5) for CTA was 3.180 ? 0.961, MSCTA 4.062 ? 0.928, and for DSA 4.588 ? 0.758 (p < 0.01). The results of this study favorite conventional angiography as the gold standard for diagnostic of intracranial aneurysms. Conclusion. The results of this study are consistent with current publications review and clearly recognize the advantages and disadvantages of diagnostic neuroradiological procedures, with DSA of brain blood vessels as a binding preoperative diagnostic procedure in cases in who it is not possible to clearly visualize the supporting blood vessel and neck of the aneurysm by using the findings of CTA, MRA and MSCTA.

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Lee, Junsoo, Hoseong Cho, Sungjo Park, Jaeyul Lee, Daewoon Seong, Ruchire Eranga Wijesinghe, Sangyeob Han, Shinheon Kim, Mansik Jeon, and Jeehyun Kim. "In Vivo Rodent Cervicothoracic Vasculature Imaging Using Photoacoustic Computed Tomography." Photonics 8, no. 8 (August 3, 2021): 312. http://dx.doi.org/10.3390/photonics8080312.

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Mice and rats are rodent specimens commonly used in multidisciplinary research. Specifically, vasculature imaging of rodents has been widely performed in preclinical studies using various techniques, such as computed tomography, magnetic resonance imaging, and ultrasound imaging. Photoacoustic CT (PACT) is a noninvasive, nonionizing optical imaging technique derived from photoacoustic tomography and benefits from using intrinsic endogenous contrast agents to produce three-dimensional volumetric data from images. In this study, a commercial PACT device was employed to assess the cervicothoracic vasculature of mouse and rat specimens, which has rarely been examined using PACT, under two conditions with depilation and skin incision. Various blood vessels, including the common carotid artery, internal/external jugular veins, cranial vena cava, internal thoracic vein, and mammary, were identified in the acquired PACT images. The difference between the depilated and skin-incised specimens also revealed the presence of branches from certain blood vessels and specific anatomical features such as the manubrium of the sternum. This study presents detailed PACT images observing the cervicothoracic vasculature of rodent specimens and is expected to be used as a reference for various preclinical experiments on mice and rats.

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Holmes, Jon, Sandra Schuh, Frank Lee Bowling, Raj Mani, and Julia Welzel. "Dynamic Optical Coherence Tomography Is a New Technique for Imaging Skin Around Lower Extremity Wounds." International Journal of Lower Extremity Wounds 18, no. 1 (January 7, 2019): 65–74. http://dx.doi.org/10.1177/1534734618821015.

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Chronic wounds such as venous leg ulcers invariably heal slowly and recur. In the case of venous leg ulcers, poor healing of chronic wounds is variously attributed to ambulatory hypertension, impaired perfusion and diffusion, presence of chronic inflammation at wound sites, lipodermatosclerosis, and senescence. The aim of this study was to investigate whether a new technique, optical coherence tomography (OCT), which permits imaging of blood capillaries in the peri-wound skin, can provide new insights into the pathology. OCT and its recent variant, dynamic OCT, permit rapid noninvasive depth-resolved imaging of the capillaries in the superficial dermis via a handheld probe, showing the morphology and density of vessels down to 20 µm in diameter. We used dynamic OCT to investigate 15 chronic wounds and assess characteristics of the vessels at the 4 poles around the wounds, the wound bed, adjacent dermatosclerosis, and unaffected skin. The results of the study show that both vessel morphology and density in the wound edges are dramatically different from that in healthy skin, showing clusters of glomuleri-like vessels (knot-like forms or clumps) and an absence of linear branching vessels, and also greater blood perfusion. Such vessel shapes are reported to be associated with tissue growth. The OCT imaging procedure was rapid and well tolerated by patients and provided new information not available from other devices. Thus, OCT appears to have great promise as a tool for the evaluation and study of chronic ulcers.

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Alexander, Mark S. M., P. S. Dias, and David Uttley. "Spontaneous subarachnoid hemorrhage and negative cerebral panangiography." Journal of Neurosurgery 64, no. 4 (April 1986): 537–42. http://dx.doi.org/10.3171/jns.1986.64.4.0537.

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✓ One hundred and forty consecutive patients who sustained proven spontaneous subarachnoid hemorrhage (SAH) with negative cerebral panangiography were studied retrospectively. Attention was directed to the presence, amount, and distribution of subarachnoid blood on computerized tomography (CT) scans. It was determined that the finding of blood on CT had a significant association with clinical grade, loss of consciousness, ventricular ratio, fixed ischemic deficit, and total of all complications, but not with epilepsy, hypertension (previously known or detected on admission), treated hydrocephalus, rebleeding, angiographic spasm, and eventual outcome (which was generally excellent on follow-up examination). The distribution of blood, predominantly around the basal cisterns, suggests leakage from ventriculostriate and thalamoperforating vessels as the cause of SAH, and closer study of these vessels is suggested.

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Petrovic, Sladjana, Aleksandar Tasic, Dragan Mihailovic, Nikola Zivkovic, Marija Vitanovic, and Dragan Stojanov. "Bilateral giant angiomyolipomas revealed after massive retroperitoneal hemorrhage: A case report." Vojnosanitetski pregled 71, no. 4 (2014): 408–12. http://dx.doi.org/10.2298/vsp1404408p.

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Introduction. Angiomyolipomas (AML) are benign neoplasms composed of fat, smooth muscle and thick-walled blood vessels in varying proportions. These tumors have a significant female predominance. Case report. We reported a 61-year-old man with spontaneous rupture of AML. Computerized tomography revealed a change in morphology of both kidneys. Multiple lesions of fat density with dilated blood vessels were found in the left kidney. The right retroperitoneum was obliterated with a giant heterogeneous mass originating from the right kidney with a massive hemorrhage, active extravasations, compression of inferior the vena cava and intraperitoneal collections. After radical nephrectomy, histological examination revealed that the tumor was composed of relative proportions of fat, smooth muscle and blood vessels. We incidentally found small renal adenoma. Conclusion. The true nature of AML is unclear, but they are usually classified as hamartomas. Angiomyolipomas are generally benign lesions, although the epithelioid angiomyolipoma, a subtype that occurs in about 3% of cases, can behavior aggressively.

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Bentley, Michael D., Maria C. Ortiz, Erik L. Ritman, and J. Carlos Romero. "The use of microcomputed tomography to study microvasculature in small rodents." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 282, no. 5 (May 1, 2002): R1267—R1279. http://dx.doi.org/10.1152/ajpregu.00560.2001.

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Appropriate nephron function is dependent on the intrarenal arrangement of blood vessels. The preferred and primary means to study the architecture of intrarenal circulation has been by filling it with opaque substances such as india ink, radio-opaque contrast material, or various polymers for study by light or scanning electron microscopy. With such methodologies, superficial vessels may obscure deep vessels and little quantitative information may be obtained. Serial-section microtomy has not been practical because of problems relating to alignment and registration of adjacent sections, lost sections, and preparation time and effort. Microcomputed tomography (micro-CT) overcomes such limitations and provides a means to study the three-dimensional architecture of filled vessels within an intact rodent kidney and to obtain more quantitative information. As an example of micro-CT's capabilities, we review the use of micro-CT to study the alterations in renal microvasculature caused by the development of liver cirrhosis after chronic bile duct ligation. In this example, micro-CT evidence shows a selective decrease in cortical vascular filling in the kidney, with a maintenance of medullary vascular filling. These changes may contribute to the salt and water retention that accompanies cirrhosis. These results indicate that micro-CT is a promising method to evaluate renal vascular architecture in the intact rodent kidney relative to physiological and pathological function.

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Shchuko, A. G., S. I. Zhukova, T. N. Iureva, and A. N. Zlobina. "Central Serous Chorioretinopathy from the Point of View of OCT-Angiography. Part 1. Chorioretinal Blood Flow Changes." Ophthalmology in Russia 15, no. 3 (October 5, 2018): 294–302. http://dx.doi.org/10.18008/1816-5095-2018-3-294-302.

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Numerous recent studies indicate that the key mechanism for the development of central serous chorioretinopathy (CSR) is damage to retinal pigment epithelium (RPE). At the same time, the reports appeared in recent years indicate that an equally important link in pathogenesis is the disturbances of the choroidal blood flow. Thus, the introduction into clinical practice of optical coherence tomography in the angiography (OCTA) mode made it possible to visualize the retinal and choroidal vessels taking into account their segmentation, which opens up prospects for studying chorioretinal blood flow in the CSR.Purpose:to reveal the regularities of the change in the choroidal blood flow in patients with SCR according to the OCTA data, to assess their informativeness and role in the pathogenesis of the disease.Patients and methods:26 patients with SCR aged 35–54 years were examined. To assess the chorioretinal blood flow, optical coherence tomography of the retina is included in the angiography mode in the scope of the diagnostic examination.Results and discussion:It has been revealed that the number of large vessels in the immediate vicinity of the RPE is increasing in SCR, i.e. the vessels move towards the retina in the direction of the least resistance. Disturbance of the hierarchy of the vasculature is an important fact, allowing to speak about pronounced hemodynamic disorders. Disturbance of the topography of large-caliber vessels is accompanied by the formation of a characteristic vascular pattern. The revealed predominance of the reticular pattern of large vessels in patients with CSR is more likely due to the presence of a significant number of bifurcations and anastomoses, as well as an increase in the proportion of crossed vessels. This may be accompanied by an increase in total vascular resistance. Consequently, the hydraulic resistance can increase at these sites, a turbulent blood flow occurs and the permeability of the vascular wall increases. Correspondence between changes in RPE and choriocapillaries was established. Taking into account that the RPE detachments from 450 to 780 (on average 515 ± 72.3) μm, revealed in the projection of the altered choriocapillaries, have comparable sizes with the value of one vascular lobe (515 × 450) μm, one can speak of a local lesion of choriocapillaries and RPE within one arteriocentric lobules.Conclusions:The revealed changes in regional blood flow are progressive and can be used as classification and prognostic criteria for choroidal dysfunction.

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Mockus, Laimonas, Mečislavas Meilūnas, Mantas Paulinas, Andrius Ušinskas, and Diana Zakarkaitė. "GENERATING OF REFORMAT SLICES IN NEURAL AND CARDIO‐TOMOGRAPHY." Mathematical Modelling and Analysis 12, no. 1 (March 31, 2007): 121–30. http://dx.doi.org/10.3846/1392-6292.2007.12.121-130.

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A lot of medical diagnostics problems are related to the reconstruction of three dimension (3D) images from the cross sections of the regions of interest. Such reconstructions are very desirable for evaluation of disease or planning of surgical treatment. This paper reviews recent 3D preprocessing work of authors in human brain blood vessels structure recognition and localization of aneurysms as well as analysis of the right ventricular of the human heart. Here we present some approximation techniques for generation of reformatted images.

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Valeeva, K. G., S. K. Perminova, A. Ya Nazipova, S. V. Kurochkin, and A. A. Yakupova. "A trial of the use of perfusion computed tomography of the brain in combination with transcranial Doppler ultrasonography of blood vessels in patients with acute cerebrovascular accident." Kazan medical journal 101, no. 1 (February 11, 2020): 124–31. http://dx.doi.org/10.17816/kmj2020-124.

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Aim. Assessment of cerebral blood flow in various vascular beds in patients with an acute cerebrovascular accident in the acute period by perfusion computed tomography in combination with transcranial Doppler ultrasonography of cerebral vessels. Methods. Data was analyzed from perfusion computed tomography of the brain and transcranial Doppler ultrasonography in 35 patients with an acute cerebrovascular accident, based at the vascular centre of the City Clinical Hospital No. 7 of Kazan. The study included 18 (51.4%) women and 17 (48.6%) men who had arrived in the first hours after a vascular accident. When analyzing the stroke subtype, atherothrombotic subtype was determined in 27 (77.1%) patients, cardioembolic subtype in 5 (14.3%) patients, and 3 (8.6%) patients had had a transient ischemic attack. Results. Perfusion computed tomography is a method that allowed evaluation of the structure of the brain, and blood supply to the anterior cerebral (in 2.9% of the studied patients), middle cerebral (in 62.9% of the studied patients), posterior cerebral (in 11.4% of the studied patients) and vertebral (in 14.2% of the studied patients) arteries of patients with a stroke. The method revealed a zone of critical perfusion (ischemic penumbra) by quantitatively processing perfusion indicators in the anterior cerebral blood flow system (decrease in rate and increase in average volume of cerebral blood flow and average transit time) and in the posterior cerebral circulation system (decrease in blood flow and prolongation of transit time) in the bed of the right vertebral artery). The method also aided the construction of perfusion maps. Transcranial Doppler ultrasonography of cerebral vessels revealed breaches in the cerebral circulation: a decrease in the linear velocity of blood flow in the right middle cerebral arterial bed and in the posterior circulatory system of blood flow in the brain, and an increase in the pulsatility index in all the studied vascular beds. Conclusion. Perfusion computed tomography of the brain in combination with transcranial Doppler ultrasonography is applicable to patients with stroke in various vascular beds, followed by determination of indications for thrombolytic therapy and thrombectomy.

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Han, Myounghee, Yongjoo Kim, Jang Ryul Park, Benjamin J. Vakoc, Wang-Yuhl Oh, and Sukyoung Ryu. "Retinal Blood Vessel Caliber Estimation for Optical Coherence Tomography Angiography Images Based on 3D Superellipsoid Modeling." International Journal of Image and Graphics 19, no. 02 (April 2019): 1950011. http://dx.doi.org/10.1142/s0219467819500116.

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Changes of retinal blood vessel calibers may reflect various retinal diseases and even several non-retinal diseases. We propose a new method to estimate retinal vessel calibers from 3D optical coherence tomography angiography (OCTA) images based on 3D modeling using superellipsoids. Taking advantage of 3D visualization of the retinal tissue microstructures in vivo provided by OCTA, our method can detect retinal blood vessels precisely, estimate their calibers reliably, and show the relative flow speed visually.

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Giacalone, Guido, Takumi Yamamoto, Florence Belva, and Akitatsu Hayashi. "Bedside 3D Visualization of Lymphatic Vessels with a Handheld Multispectral Optoacoustic Tomography Device." Journal of Clinical Medicine 9, no. 3 (March 17, 2020): 815. http://dx.doi.org/10.3390/jcm9030815.

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Identification of lymphatics by Indocyanine Green (ICG) lymphography in patients with severe lymphedema is limited due to the overlying dermal backflow. Nor can the method detect deep and/or small vessels. Multispectral optoacoustic tomography (MSOT), a real-time three- dimensional (3D) imaging modality which allows exact spatial identification of absorbers in tissue such as blood and injected dyes can overcome these hurdles. However, MSOT with a handheld probe has not been performed yet in lymphedema patients. We conducted a pilot study in 11 patients with primary and secondary lymphedema to test whether lymphatic vessels could be detected with a handheld MSOT device. In eight patients, we could not only identify lymphatics and veins but also visualize their position and contractility. Furthermore, deep lymphatic vessels not traceable by ICG lymphography and lymphatics covered by severe dermal backflow, could be clearly identified by MSOT. In three patients, two of which had advanced stage lymphedema, only veins but no lymphatic vessels could be identified. We found that MSOT can identify and image lymphatics and veins in real-time and beyond the limits of near-infrared technology during a single bedside examination. Given its easy use and high accuracy, the handheld MSOT device is a promising tool in lymphatic surgery.

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Vargas, Gracie, Allison Readinger, Susan S. Dozier, and Ashley J. Welch. "Morphological Changes in Blood Vessels Produced by Hyperosmotic Agents and Measured by Optical Coherence Tomography ¶." Photochemistry and Photobiology 77, no. 5 (May 1, 2007): 541–49. http://dx.doi.org/10.1562/0031-8655(2003)0770541mcibvp2.0.co2.

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Vargas, Gracie, Allison Readinger, Susan S. Dozier, and Ashley J. Welch. "Morphological Changes in Blood Vessels Produced by Hyperosmotic Agents and Measured by Optical Coherence Tomography¶." Photochemistry and Photobiology 77, no. 5 (2003): 541. http://dx.doi.org/10.1562/0031-8655(2003)077<0541:mcibvp>2.0.co;2.

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Kehlet Barton, J., J. A. Izatt, M. D. Kulkarni, S. Yazdanfar, and A. J. Welch. "Three-Dimensional Reconstruction of Blood Vessels from in vivo Color Doppler Optical Coherence Tomography Images." Dermatology 198, no. 4 (1999): 355–61. http://dx.doi.org/10.1159/000018148.

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Peng, Shizhao, Yuanzhen Jiang, Kailin Zhang, Chuanchao Wu, Danni Ai, Jian Yang, Yongtian Wang, and Yong Huang. "Cooperative Three-View Imaging Optical Coherence Tomography for Intraoperative Vascular Evaluation." Applied Sciences 8, no. 9 (September 4, 2018): 1551. http://dx.doi.org/10.3390/app8091551.

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Real-time intraoperative optical coherence tomography (OCT) imaging of blood vessels after anastomosis operation can provide important information the vessel, such as patency, flow speed, and thrombosis morphology. Due to the strong scattering and absorption effect of blood, normal OCT imaging suffers from the problem of incomplete cross-sectional view of the vessel under investigation when the diameter is large. In this work, we present a novel cooperative three-view imaging spectral domain optical coherence tomography system for intraoperative exposed vascular imaging. Two more side views (left view and right view) were realized through a customized sample arm optical design and corresponding mechanical design and fabrication, which could generate cross-sectional images from three circumferential view directions to achieve a larger synthetic field of view (FOV). For each view, the imaging depth was 6.7 mm (in air) and the lateral scanning range was designed to be 3 mm. Therefore, a shared synthetic rectangle FOV of 3 mm × 3 mm was achieved through cooperative three view scanning. This multi-view imaging method can meet the circumferential imaging demands of vessels with an outer diameter less than 3 mm. Both phantom tube and rat vessel imaging confirmed the increased system FOV performance. We believe the intraoperative application of this cooperative three-imaging optical coherence tomography for objective vascular anastomosis evaluation can benefit patient outcomes in the future.

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Kindlmann, Gordon L., David M. Weinstein, Greg M. Jones, Christopher R. Johnson, Mario R. Capecchi, and Charles Keller. "Practical Vessel Imaging by Computed Tomography in Live Transgenic Mouse Models for Human Tumors." Molecular Imaging 4, no. 4 (October 1, 2005): 7290.2005.05166. http://dx.doi.org/10.2310/7290.2005.05166.

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Contrast-enhanced small-animal computed tomography is an economical and highly quantitative tool for serially examining tumor development in situ, for analyzing the network of blood vessels that nourish them, and for following the response of tumors to preclinical therapeutic intervention(s). We present practical considerations for visualizing the vascular network of transgenic mouse tumors. Using a long-acting iodinated triglyceride blood-pool contrast agent, we present optimized scanner acquisition parameters and volume-rendering techniques for examining the intermediate and large vessels of complex spontaneous tumors (e.g., alveolar rhabdomyosarcomas) in transgenic mice. Our findings indicate that multiple-frame, 360–720 view acquisitions were mandatory for clarifying bone and soft tissue from vessel contrast. This finding was consistent in visualizations using a one-dimensional transfer function where voxel color and opacity was assigned in proportion to CT value and a two-dimensional transfer function where voxel color and opacity was assigned in proportion to CT value and gradient magnitude. This study lays a groundwork for the qualitative and quantitative assessment of anti-angiogenesis preclinical studies using transgenic mice.

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Павлюченко, О. В., Г. Ф. Малиновский, and Н. Н. Сиденко. "Optical Coherent Tomography-Angiography in Early Diagnostics and Choosing the Treatment of Primary Open-Angle Glaucoma Treatment." Офтальмология. Восточная Европа, no. 2 (July 17, 2020): 230–39. http://dx.doi.org/10.34883/pi.2020.10.2.021.

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Цель. Проанализировать и оценить возможности оптической когерентной томографии с функцией ангиографии в ранней диагностике и выборе тактики лечения пациентов с первичной открытоугольной глаукомой (ПОУГ).Материалы и методы. По литературным данным, глаукома сопровождается ослаблением кровотока в головке зрительного нерва (ГЗН) и сетчатке. Согласно сосудистой теории патогенеза глаукомной оптиконейропатии в развитии заболевания ведущую роль играет снижение гемоперфузии диска зрительного нерва (ДЗН) с развитием его ишемии [8, 10]. Для объективной оценки состояния микроциркуляторного русла диска зрительного нерва при ПОУГ, понимания причин и степени выраженности нарушений кровоснабжения ГЗН нужны более совершенные методы исследования [2, 15].Результаты и обсуждение. Метод оптической когерентной томографии-ангиографии (ОКТА) позволяет четко визуализировать глазные кровеносные сосуды за счет улучшения соотношения оптических сигналов и автоматического удаления ошибок движения [5]. Анализ движения крови по сосудам осуществляется с использованием данных об изменении отраженной от эритроцитов амплитуды сигнала. Это позволяет дифференцировать кровеносные сосуды от окружающих тканей на всей глубине сканирования [9, 10].Выводы:Оптическая когерентная томография-ангиография в исследовании кровотока ГЗН, сетчатки и хориоидеи является современным неинвазивным, безопасным и информативным методом оценки микроциркуляции глаза.Трехмерность ОКТА-изображения позволяет исследовать изолированные капиллярные сети в разных слоях сетчатки и ДЗН и предоставляет дополнительные возможности в ранней диагностике глаукомы.По данным ОКТА выявлено истончение микрососудистых сплетений перипапиллярной области, поверхностных сосудов ДЗН и более глубоких сосудов решетчатой пластинки, что указывает на возможное снижение гемоперфузии у пациентов с глаукомой.Индекс кровотока в ГЗН строго коррелирует с параметрами поля зрения, а соответственно и со стадией глаукомы, что позволяет объективно оценивать эффективность применения различных методов лечения первичной открытоугольной глаукомы. Purpose. To analyze and evaluate the possibilities of OCT with angiography function in early diagnosis and the choice of treatment tactics for patients with primary open-angle glaucoma.Materials and methods. According to published data, glaucoma is accompanied by a weakening of blood flow in the optic nerve head (ONH) and the retina. According to the vascular theory of the pathogenesis of glaucoma optoneuropathy (GON) in the development of the disease, the leading role is played by the reduction of hemoperfusion of the optic nerve disc (OND) with the development of its ischemia [8,10]. For an objective assessment of the state of the microcirculatory bed of the optic disc with POAG, understanding the causes and severity of blood supply disorders of ONH, more advanced research methods are needed [2, 15].Results and discussion. The OCTA method allows you to clearly visualize the ocular blood vessels by improving the ratio of optical signals and automatically removing motion errors [5]. Analysis of blood flow through the vessels is carried out using data on the signal amplitude reflected from red blood cells. This allows us to differentiate blood vessels from surrounding tissues at the entire scanning depth [9,10].Conclusions.Optical coherence tomography-angiography in the study of blood flow of ONH, retina and choroidisamodernnon-invasive, safeandinformativemethodforassessingeyemicrocirculation.Three-dimensionality of the OCTA image allows the study of isolated capillary networks in different layers of the retina and optic disc and provides additional opportunities in the early diagnosis of glaucoma.According to OCTA data, a thinning of the microvascular plexuses of the peripapillary region, superficial OND vessels and deeper vessels of the ethmoid plate was revealed, which indicates a possible decrease in hemoperfusion in patients with glaucoma.The blood flow index in the ONH strictly correlates with the parameters of the field of view, and accordingly with the stage of glaucoma, which makes it possible to objectively evaluate the effectiveness of various methods of treatment of primary open-angle glaucoma.

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Bitzer, Michael, Lars Wöckel, Andreas R. Luft, Ajay K. Wakhloo, Dirk Petersen, Holger Opitz, Theo Sievert, Ulrike Ernemann, and Karsten Voigt. "The importance of pial blood supply to the development of peritumoral brain edema in meningiomas." Neurosurgical Focus 2, no. 4 (April 1997): E6. http://dx.doi.org/10.3171/foc.1997.2.4.7.

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The authors studied the pial and dural blood supplies in 74 intracranial meningiomas and quantified their associated peritumoral brain edema (PTBE). The extent and localization of pial blush in relation to the total tumor volume were determined angiographically. The amount of edema and tumor size were calculated using computerized tomography. The edema-tumor volume ratio was defined as Edema Index (EI). There were 49 meningiomas with PTBE; of those tumors, 46 were supplied by pial vessels, and three were supplied exclusively by dural vessels. Tumors without PTBE showed no pial blush. The mean EI in meningiomas with pial blush was significantly larger (EI = 3.0) than in meningiomas without pial supply (EI = 1.1; p < 0.0001). Meningiomas in which 10% of the whole tumor volume was supplied by pial vessels had only a small mean EI of 2.2, whereas tumors with pial blood supply greater than or equal to 20% had a mean EI of 3.3 (p < 0.026). In 69.9% of cases with pial blood supply, major portions of the edema were located adjacent to the tumor region supplied by pial vessels. Edema index differences among tumors of different subgroups, as defined by size or histology, were significantly related to the pial supply in each subset. Thus, pial blood supply may be causative for the development of PTBE in meningiomas.

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Brudin, L. H., S. O. Valind, C. G. Rhodes, D. R. Turton, and J. M. Hughes. "Regional lung hematocrit in humans using positron emission tomography." Journal of Applied Physiology 60, no. 4 (April 1, 1986): 1155–63. http://dx.doi.org/10.1152/jappl.1986.60.4.1155.

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Regional lung hematocrit ratio (R) was measured in five normal subjects and five patients (2 with pneumonia, 2 with nephrotic syndrome with anemia, and 1 with pancreatitis) using positron emission tomography, a red cell marker 11CO, and a plasma marker [methyl-11C]albumin). The measurements were made in a transaxial thoracic section at midheart level with the subject in supine posture and with a spatial resolution of 1.7 cm. The normal regional hematocrit ratio (means +/- SE) calculated for the lung was 0.90 +/- 0.014, 0.94 +/- 0.023 for the thoracic wall, and 1.00 +/- 0.003 for the heart chambers. The regional lung hematocrit ratio in the patients ranged between 0.81 and 0.86. No correlation was found among the regional lung hematocrit ratio and regional blood volume, lung extravascular density, and the peripheral hematocrit (obtained from venous blood samples). To the extent that 70% of the pulmonary blood in the field of view is in larger vessels with normal hematocrit, the hematocrit in the capillary bed is approximately two-thirds that of the peripheral venous value. Blood volume measurements on the basis of single vascular tracers need to take account of these results.

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Wiszniak, Sophie, Francesca E. Mackenzie, Peter Anderson, Samuela Kabbara, Christiana Ruhrberg, and Quenten Schwarz. "Neural crest cell-derived VEGF promotes embryonic jaw extension." Proceedings of the National Academy of Sciences 112, no. 19 (April 28, 2015): 6086–91. http://dx.doi.org/10.1073/pnas.1419368112.

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Abstract:

Jaw morphogenesis depends on the growth of Meckel’s cartilage during embryogenesis. However, the cell types and signals that promote chondrocyte proliferation for Meckel’s cartilage growth are poorly defined. Here we show that neural crest cells (NCCs) and their derivatives provide an essential source of the vascular endothelial growth factor (VEGF) to enhance jaw vascularization and stabilize the major mandibular artery. We further show in two independent mouse models that blood vessels promote Meckel’s cartilage extension. Coculture experiments of arterial tissue with NCCs or chondrocytes demonstrated that NCC-derived VEGF promotes blood vessel growth and that blood vessels secrete factors to instruct chondrocyte proliferation. Computed tomography and X-ray scans of patients with hemifacial microsomia also showed that jaw hypoplasia correlates with mandibular artery dysgenesis. We conclude that cranial NCCs and their derivatives provide an essential source of VEGF to support blood vessel growth in the developing jaw, which in turn is essential for normal chondrocyte proliferation, and therefore jaw extension.

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Journal articles on the topic 'Blood-vessels Tomography'

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