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Zhu L, Wang M, Liu Y, Fu P, Zhang W, Zhang H, Roe AW, Xi W. Single-microvessel occlusion produces lamina-specific microvascular flow vasodynamics and signs of neurodegenerative change. Cell Rep 2023; 42:112469. [PMID: 37141094 DOI: 10.1016/j.celrep.2023.112469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 01/12/2023] [Accepted: 04/18/2023] [Indexed: 05/05/2023] Open
Abstract
Recent studies have highlighted the importance of understanding the architecture and function of microvasculature, and dysfunction of these microvessels may underlie neurodegenerative disease. Here, we utilize a high-precision ultrafast laser-induced photothrombosis (PLP) method to occlude single capillaries and then quantitatively study the effects on vasodynamics and surrounding neurons. Analysis of the microvascular architecture and hemodynamics after single-capillary occlusion reveals distinct changes upstream vs. downstream branches, which shows rapid regional flow redistribution and local downstream blood-brain barrier (BBB) leakage. Focal ischemia via capillary occlusions surrounding labeled target neurons induces dramatic and rapid lamina-specific changes in neuronal dendritic architecture. Further, we find that micro-occlusion at two different depths within the same vascular arbor results in distinct effects on flow profiles in layers 2/3 vs layer 4. The current results reveal laminar-scale regulation distinctions in microinfarct response and raise the possibility that relatively greater impacts on microvascular function contribute to cognitive decline in neurodegenerative disease.
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Affiliation(s)
- Liang Zhu
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310020, China; Interdisciplinary Institute of Neuroscience and Technology (ZIINT), College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027, China
| | - Mengqi Wang
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310020, China
| | - Yin Liu
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310020, China
| | - Peng Fu
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310020, China
| | - Weijie Zhang
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027, China
| | - Hequn Zhang
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310020, China
| | - Anna Wang Roe
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310020, China; MOE Frontier Science Center for Brain Research and Brain Machine Integration, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Biomedical Engineering of the Ministry of Education, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027, China.
| | - Wang Xi
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310020, China; MOE Frontier Science Center for Brain Research and Brain Machine Integration, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Biomedical Engineering of the Ministry of Education, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou 310027, China.
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Zhu L, Wang M, Fu P, Liu Y, Zhang H, Roe AW, Xi W. Precision 1070 nm Ultrafast Laser-Induced Photothrombosis of Depth-Targeted Vessels In Vivo. SMALL METHODS 2023; 7:e2200917. [PMID: 36286988 DOI: 10.1002/smtd.202200917] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Revised: 09/09/2022] [Indexed: 06/16/2023]
Abstract
The cerebrovasculature plays an essential role in neurovascular and homeostatic functions in health and disease conditions. Many efforts have been made for developing vascular thrombosis methods to study vascular dysfunction in vivo, while technical challenges remain, such as accuracy and depth-selectivity to target a single vessel in the cerebral cortex. Herein, this paper first demonstrates the evaluation and quantification of the feasibility and effects of Rose Bengal (RB)-induced photothrombosis with 720-1070 nm ultrafast lasers in a raster scan. A flexible and reproducible approach is then proposed to employ a 1070 nm ultrafast laser with a spiral scan for producing RB-induced occlusion, which is described as precision ultrafast laser-induced photothrombosis (PLP). Combine with two-photon microscopy imaging, this PLP displays highly precise and fast occlusion induction of various vessel types, sizes, and depths, which enhances the precision and power of the photothrombosis protocol. Overall, the PLP method provides a real-time, practical, precise, and depth-selected single-vessel photothrombosis technology in the cerebral cortex with commercially available optical equipment, which is crucial for exploring brain vascular function with high spatial-temporal resolution in the brain.
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Affiliation(s)
- Liang Zhu
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310020, China
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, 310027, China
| | - Mengqi Wang
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310020, China
| | - Peng Fu
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310020, China
| | - Yin Liu
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310020, China
| | - Hequn Zhang
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310020, China
| | - Anna Wang Roe
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310020, China
- MOE Frontier Science Center for Brain Research and Brain Machine Integration, Zhejiang University, Hangzhou, 310058, China
- Key Laboratory of Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, 310027, China
| | - Wang Xi
- Interdisciplinary Institute of Neuroscience and Technology (ZIINT), the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, 310020, China
- MOE Frontier Science Center for Brain Research and Brain Machine Integration, Zhejiang University, Hangzhou, 310058, China
- Key Laboratory of Biomedical Engineering of Ministry of Education, College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, 310027, China
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Choi WJ, Li Y, Wang RK. Monitoring Acute Stroke Progression: Multi-Parametric OCT Imaging of Cortical Perfusion, Flow, and Tissue Scattering in a Mouse Model of Permanent Focal Ischemia. IEEE TRANSACTIONS ON MEDICAL IMAGING 2019; 38:1427-1437. [PMID: 30714910 PMCID: PMC6660833 DOI: 10.1109/tmi.2019.2895779] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Cerebral ischemic stroke causes injury to brain tissue characterized by a complex cascade of neuronal and vascular events. Imaging during the early stages of its development allows prediction of tissue infarction and penumbra so that optimal intervention can be determined in order to salvage brain function impairment. Therefore, there is a critical need for novel imaging techniques that can characterize brain injury in the earliest phases of the ischemic stroke. This paper examined optical coherence tomography (OCT) for imaging acute injury in experimental ischemic stroke in vivo. Based on endogenous optical scattering signals provided by OCT imaging, we have developed a single, integrated imaging platform enabling the measurement of changes in blood perfusion, blood flow, erythrocyte velocity, and light attenuation within a cortical tissue, during focal cerebral ischemia in a mouse model. During the acute phase (from 5 min to the first few hours following the blood occlusion), the multi-parametric OCT imaging revealed multiple hemodynamic and tissue scattering responses in vivo, including cerebral blood flow deficits, capillary non-perfusion, displacement of penetrating vessels, and increased light attenuation in the cortical tissue at risk that are spatially correlated with the infarct core, as determined by postmortem staining with triphenyltetrazolium chloride. The use of multi-parametric OCT imaging may aid in the comprehensive evaluation of ischemic lesions during the early stages of stroke, thereby providing essential knowledge for guiding treatment decisions.
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Affiliation(s)
- Woo June Choi
- School of Electrical and Electronics Engineering, College of ICT Engineering, Chung-Ang University, Seoul, 06974, Korea
| | - Yuandong Li
- Department of Bioengineering, University of Washington, Seattle WA 98195, USA
| | - Ruikang K. Wang
- Corresponding author, phone: 206-616-5025; fax: 206-616-5025;
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Wei L, Wei ZZ, Jiang MQ, Mohamad O, Yu SP. Stem cell transplantation therapy for multifaceted therapeutic benefits after stroke. Prog Neurobiol 2017; 157:49-78. [PMID: 28322920 PMCID: PMC5603356 DOI: 10.1016/j.pneurobio.2017.03.003] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 01/30/2017] [Accepted: 03/05/2017] [Indexed: 02/06/2023]
Abstract
One of the exciting advances in modern medicine and life science is cell-based neurovascular regeneration of damaged brain tissues and repair of neuronal structures. The progress in stem cell biology and creation of adult induced pluripotent stem (iPS) cells has significantly improved basic and pre-clinical research in disease mechanisms and generated enthusiasm for potential applications in the treatment of central nervous system (CNS) diseases including stroke. Endogenous neural stem cells and cultured stem cells are capable of self-renewal and give rise to virtually all types of cells essential for the makeup of neuronal structures. Meanwhile, stem cells and neural progenitor cells are well-known for their potential for trophic support after transplantation into the ischemic brain. Thus, stem cell-based therapies provide an attractive future for protecting and repairing damaged brain tissues after injury and in various disease states. Moreover, basic research on naïve and differentiated stem cells including iPS cells has markedly improved our understanding of cellular and molecular mechanisms of neurological disorders, and provides a platform for the discovery of novel drug targets. The latest advances indicate that combinatorial approaches using cell based therapy with additional treatments such as protective reagents, preconditioning strategies and rehabilitation therapy can significantly improve therapeutic benefits. In this review, we will discuss the characteristics of cell therapy in different ischemic models and the application of stem cells and progenitor cells as regenerative medicine for the treatment of stroke.
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Affiliation(s)
- Ling Wei
- Laboratories of Stem Cell Biology and Regenerative Medicine, Department of Neurology, Experimental Research Center and Neurological Disease Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA; Department of Neurology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Zheng Z Wei
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Michael Qize Jiang
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Osama Mohamad
- Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA
| | - Shan Ping Yu
- Laboratories of Stem Cell Biology and Regenerative Medicine, Department of Neurology, Experimental Research Center and Neurological Disease Center, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, China; Department of Anesthesiology, Emory University School of Medicine, Atlanta, GA 30322, USA.
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Jia JM, Chowdary PD, Gao X, Ci B, Li W, Mulgaonkar A, Plautz EJ, Hassan G, Kumar A, Stowe AM, Yang SH, Zhou W, Sun X, Cui B, Ge WP. Control of cerebral ischemia with magnetic nanoparticles. Nat Methods 2017; 14:160-166. [PMID: 27941784 PMCID: PMC5792654 DOI: 10.1038/nmeth.4105] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 11/04/2016] [Indexed: 12/21/2022]
Abstract
The precise manipulation of microcirculation in mice can facilitate mechanistic studies of brain injury and repair after ischemia, but this manipulation remains a technical challenge, particularly in conscious mice. We developed a technology that uses micromagnets to induce aggregation of magnetic nanoparticles to reversibly occlude blood flow in microvessels. This allowed induction of ischemia in a specific cortical region of conscious mice of any postnatal age, including perinatal and neonatal stages, with precise spatiotemporal control but without surgical intervention of the skull or artery. When combined with longitudinal live-imaging approaches, this technology facilitated the discovery of a feature of the ischemic cascade: selective loss of smooth muscle cells in juveniles but not adults shortly after onset of ischemia and during blood reperfusion.
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Affiliation(s)
- Jie-Min Jia
- Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | | | - Xiaofei Gao
- Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Bo Ci
- Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Wenjun Li
- Center for Neuroscience Discovery, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Aditi Mulgaonkar
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Erik J Plautz
- Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Gedaa Hassan
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Amit Kumar
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Ann M Stowe
- Department of Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Shao-Hua Yang
- Center for Neuroscience Discovery, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Wei Zhou
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics-HuaZhong University of Science and Technology, Wuhan, China
| | - Xiankai Sun
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Bianxiao Cui
- Department of Chemistry, Stanford University, Stanford, California, USA
| | - Woo-Ping Ge
- Children's Research Institute, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas, USA
- Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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Dziennis S, Qin J, Shi L, Wang RK. Macro-to-micro cortical vascular imaging underlies regional differences in ischemic brain. Sci Rep 2015; 5:10051. [PMID: 25941797 PMCID: PMC4419594 DOI: 10.1038/srep10051] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2014] [Accepted: 03/19/2015] [Indexed: 01/05/2023] Open
Abstract
The ability to non-invasively monitor and quantify hemodynamic responses down to the capillary level is important for improved diagnosis, treatment and management of neurovascular disorders, including stroke. We developed an integrated multi-functional imaging system, in which synchronized dual wavelength laser speckle contrast imaging (DWLS) was used as a guiding tool for optical microangiography (OMAG) to test whether detailed vascular responses to experimental stroke in male mice can be evaluated with wide range sensitivity from arteries and veins down to the capillary level. DWLS enabled rapid identification of cerebral blood flow (CBF), prediction of infarct area and hemoglobin oxygenation over the whole mouse brain and was used to guide the OMAG system to hone in on depth information regarding blood volume, blood flow velocity and direction, vascular architecture, vessel diameter and capillary density pertaining to defined regions of CBF in response to ischemia. OMAG-DWLS is a novel imaging platform technology to simultaneously evaluate multiple vascular responses to ischemic injury, which can be useful in improving our understanding of vascular responses under pathologic and physiological conditions, and ultimately facilitating clinical diagnosis, monitoring and therapeutic interventions of neurovascular diseases.
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Affiliation(s)
- Suzan Dziennis
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, USA
| | - Jia Qin
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, USA
| | - Lei Shi
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, USA
| | - Ruikang K Wang
- Department of Bioengineering, University of Washington, Seattle, Washington 98195, USA
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Wang H, Yang X, Wang Z, Deng Z, Gong H, Luo Q. Early monitoring of cerebral hypoperfusion in rats by laser speckle imaging and functional photoacoustic microscopy. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:061207. [PMID: 22734737 DOI: 10.1117/1.jbo.17.6.061207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Because cerebral hypoperfusion brings damage to the brain, prevention of cerebrovascular diseases correlative to hypoperfusion by studying animal models makes great sense. Since complicated cerebrovascular adaptive changes in hypoperfusion could not be revealed only by cerebral blood flow (CBF) velocity imaging, we performed multi-parameter imaging by combining laser speckle imaging and functional photoacoustic microscopy. The changes in CBF, hemoglobin oxygen saturation (SO(2)), and total hemoglobin concentration (HbT) in single blood vessels of ipsilateral cortex were observed during transient cerebral hypoperfusion by ligating the unilateral common carotid artery in rats. CBF, SO(2), and HbT, respectively, decreased to 37 ± 3%, 71 ± 7.5%, and 92 ± 1.3% of baseline in 6 s immediately after occlusion, and then recovered to 77 ± 4.8%, 84 ± 8%, and 96 ± 2% of baseline in 60 s. These parameters presented the decrease with different degree and the following recovery over time after ligation, the recovery of SO(2) lagged behind those of CBF and HbT, which had the similar response. The results demonstrated that complete monitoring of both cerebral hemodynamic response and oxygen metabolic changes occurred at the earliest period of cerebral hypoperfusion was possible by using the two image modalities with high temporal and spatial resolution.
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Affiliation(s)
- Hui Wang
- Huazhong University of Science and Technology, Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, 1037 Luoyu Road, Wuhan 430074, China
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Peuser J, Belhaj-Saif A, Hamadjida A, Schmidlin E, Gindrat AD, Völker AC, Zakharov P, Hoogewoud HM, Rouiller EM, Scheffold F. Follow-up of cortical activity and structure after lesion with laser speckle imaging and magnetic resonance imaging in nonhuman primates. JOURNAL OF BIOMEDICAL OPTICS 2011; 16:096011. [PMID: 21950925 DOI: 10.1117/1.3625287] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The nonhuman primate model is suitable to study mechanisms of functional recovery following lesion of the cerebral cortex (motor cortex), on which therapeutic strategies can be tested. To interpret behavioral data (time course and extent of functional recovery), it is crucial to monitor the properties of the experimental cortical lesion, induced by infusion of the excitotoxin ibotenic acid. In two adult macaque monkeys, ibotenic acid infusions produced a restricted, permanent lesion of the motor cortex. In one monkey, the lesion was monitored over 3.5 weeks, combining laser speckle imaging (LSI) as metabolic readout (cerebral blood flow) and anatomical assessment with magnetic resonance imaging (T2-weighted MRI). The cerebral blood flow, measured online during subsequent injections of the ibotenic acid in the motor cortex, exhibited a dramatic increase, still present after one week, in parallel to a MRI hypersignal. After 3.5 weeks, the cerebral blood flow was strongly reduced (below reference level) and the hypersignal disappeared from the MRI scan, although the lesion was permanent as histologically assessed post-mortem. The MRI data were similar in the second monkey. Our experiments suggest that LSI and MRI, although they reflect different features, vary in parallel during a few weeks following an excitotoxic cortical lesion.
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Affiliation(s)
- Jörn Peuser
- University of Fribourg, Department of Physics, Ch. du Musée 3, CH-1700 Fribourg, Switzerland
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Tang X, Feng N, Sun X, Li P, Luo Q. Portable laser speckle perfusion imaging system based on digital signal processor. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:125110. [PMID: 21198054 DOI: 10.1063/1.3505118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The ability to monitor blood flow in vivo is of major importance in clinical diagnosis and in basic researches of life science. As a noninvasive full-field technique without the need of scanning, laser speckle contrast imaging (LSCI) is widely used to study blood flow with high spatial and temporal resolution. Current LSCI systems are based on personal computers for image processing with large size, which potentially limit the widespread clinical utility. The need for portable laser speckle contrast imaging system that does not compromise processing efficiency is crucial in clinical diagnosis. However, the processing of laser speckle contrast images is time-consuming due to the heavy calculation for enormous high-resolution image data. To address this problem, a portable laser speckle perfusion imaging system based on digital signal processor (DSP) and the algorithm which is suitable for DSP is described. With highly integrated DSP and the algorithm, we have markedly reduced the size and weight of the system as well as its energy consumption while preserving the high processing speed. In vivo experiments demonstrate that our portable laser speckle perfusion imaging system can obtain blood flow images at 25 frames per second with the resolution of 640 × 480 pixels. The portable and lightweight features make it capable of being adapted to a wide variety of application areas such as research laboratory, operating room, ambulance, and even disaster site.
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Affiliation(s)
- Xuejun Tang
- Britton Chance Center for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China
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Wang L, Ren W, Fan CQ, Li YH, Zhang X, Yu J, Zhao GC, Zhao XY. Full-thickness endoscopic resection of nonintracavitary gastric stromal tumors: a novel approach. Surg Endosc 2010; 25:641-7. [PMID: 20589511 DOI: 10.1007/s00464-010-1189-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2009] [Accepted: 06/09/2010] [Indexed: 12/19/2022]
Abstract
BACKGROUND Until now, the conventional treatment of stromal tumors has been primarily open surgery or laparoscopic excision. The use of combined laparoscopic/endoscopic surgeries has been investigated, but endoscopic therapy alone has been limited to en bloc resection or nucleus removal of intracavitary tumors with diameters<2 cm. Nonintracavitary and intramural gastric stromal tumors preclude the use of endoscopic resection due to the risk of gastric perforation. This study was designed to show the safety and effectiveness of full-thickness endoscopic resection of nonintracavitary stromal tumors based on our direct experience. METHODS A total of 109 consecutive patients with nonintracavitary gastric stromal tumors<4 cm in diameter underwent surgical treatment; 66 patients received endoscopic surgery and 43 patients received laparoscopic surgery. RESULTS No significant differences existed between the two groups in terms of demographics and clinical characteristics, and no tumor exceeded 3.5 cm in size. Median operation times (endoscopic group, 53.6 min; laparoscopic group, 139 min) and hospitalization fees of the endoscopic group were significantly lower than those of the laparoscopic group with significant median hospital stays (8 days for endoscopic group; 6 days for laparoscopic group). No intraoperative complications occurred in the laparoscopic group and complete removal of tumors was achieved in the endoscopic group. Postoperative complications occurred in 6 patients of 43 who underwent laparoscopic surgery and 17 patients of 66 who underwent endoscopic surgery, representing a significant difference; the size of the lesion correlated positively with the occurrence of complications. CONCLUSIONS Endoscopic resection is safe and effective for treating nonintracavitary stromal tumors. The endoscopic natural-cavity technique produced less surgical injury to the patients and preserved the anatomy of intra-abdominal structures. In addition, the endoscopic technique reduced operative times, postoperative bleeding, and costs.
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Affiliation(s)
- Lei Wang
- Department of Gastroenterology, Xinqiao Hospital, Third Military Medical University, 1# Xinqiao Street, Chongqing, 400037, China
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11
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Abstract
Laser speckle imaging (LSI) involves analysis of reflectance images collected during coherent optical excitation of an object to compute wide-field maps of tissue blood flow. An intrinsic limitation of LSI for resolving microvascular architecture is that its signal depends on relative motion of interrogated red blood cells. Hence, with LSI, small-diameter arterioles, venules, and capillaries are difficult to resolve due to the slow flow speeds associated with such vasculature. Furthermore, LSI characterization of subsurface blood flow is subject to blurring due to scattering, further limiting the ability of LSI to resolve or quantify blood flow in small vessels. Here, we show that magnetic activation of superparamagnetic iron oxide (SPIO) nanoparticles modulate the speckle flow index (SFI) values estimated from speckle contrast analysis of collected images. With application of an ac magnetic field to a solution of stagnant SPIO particles, an apparent increase in SFI is induced. Furthermore, with application of a focused dc magnetic field, a focal decrease in SFI values is induced. Magnetomotive LSI may enable wide-field mapping of suspicious tissue regions, enabling subsequent high-resolution optical interrogation of these regions. Similarly, subsequent photoactivation of intravascular SPIO nanoparticles could then be performed to induce selective photothermal destruction of unwanted vasculature.
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Affiliation(s)
- Jeehyun Kim
- Kyungpook National University, Electrical and Computer Engineering, Daegu, South Korea
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Wang Z, Luo W, Li P, Qiu J, Luo Q. Acute hyperglycemia compromises cerebral blood flow following cortical spreading depression in rats monitored by laser speckle imaging. JOURNAL OF BIOMEDICAL OPTICS 2008; 13:064023. [PMID: 19123669 DOI: 10.1117/1.3041710] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Hyperglycemia and cortical spreading depression (CSD) are possible factors that worsen the outcome of ischemic stroke, and it is probable that there is a longterm cooperative effect of hyperglycemia and CSD on cerebral blood flow (CBF). Long-lasting and full-field observation of changes in CBF following CSD in vivo during acute hyperglycemia in rats might show whether this is the case. Here, we utilized laser speckle imaging to study influences of acute hyperglycemia on CBF at the level of individual vascular compartments for 3 h in normal rats and those with CSD. It is shown that there are extensive increases of CBF at the arteriole and parenchyma over the normal rat cortex during acute hyperglycemia, whereas there is no significant change in CBF at the venule. We also find that, at all vascular compartments, after the glucose administration there is a stepwise reduction of CBF following CSD, but after saline injection CBF following CSD is close to the baseline. Our results indicate that acute hyperglycemia could aggravate the severity of decrease in CBF following CSD, suggesting possible mechanisms by which hyperglycemia exacerbates cerebral damage after ischemic stroke.
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Affiliation(s)
- Zhen Wang
- Huazhong University of Science and Technology, Wuhan National Laboratory for Optoelectronics, Britton Chance Center for Biomedical Photonics, Wuhan 430074, China
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