Journal articles: 'Quantitative magnetic resonance angiography'

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Clifton, Andrew. "Quantitative Magnetic Resonance Angiography." Stroke 40, no. 3 (March 2009): 676. http://dx.doi.org/10.1161/strokeaha.108.529297.

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Kellner-Weldon, F. "Quantitative Magnetic Resonance Angiography." Clinical Neuroradiology 22, no. 1 (February 4, 2012): 115–18. http://dx.doi.org/10.1007/s00062-012-0131-8.

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Amin-Hanjani, Sepideh, John H. Shin, Meide Zhao, Xinjian Du, and Fady T. Charbel. "Evaluation of extracranial–intracranial bypass using quantitative magnetic resonance angiography." Journal of Neurosurgery 106, no. 2 (February 2007): 291–98. http://dx.doi.org/10.3171/jns.2007.106.2.291.

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Object To date, angiography has been the primary modality for assessing graft patency following extracranial–intracranial bypass. The utility of a noninvasive and quantitative method of assessing bypass function postoperatively was evaluated using quantitative magnetic resonance (MR) angiography. Methods One hundred one cases of bypass surgery performed over a 5.5-year period at a single institution were reviewed. In 62 cases, both angiographic and quantitative MR angiographic data were available. Intraoperative flow measurements were available in 13 cases in which quantitative MR angiography was performed during the early postoperative period (within 48 hours after surgery). There was excellent correlation between quantitative MR angiographic flow and angiographic findings over the mean 10 months of imaging follow up. Occluded bypasses were consistently absent on quantitative MR angiograms (four cases). The flow rates were significantly lower in those bypasses that became stenotic or reduced in diameter as demonstrated by follow-up angiography (nine cases) than in those bypasses that remained fully patent (mean ± standard error of the mean, 37 ± 13 ml/minute compared with 105 ± 7 ml/minute, p = 0.001). Flows were appreciably lower in poorly functioning bypasses for both vein and in situ arterial grafts. All angiographically poor bypasses (nine cases) were identifiable by absolute flows of less than 20 ml/minute or a reduction in flow greater than 30% within 3 months. Good correlation was seen between intraoperative flow measurements and early postoperative quantitative MR angiographic flow measurements (13 cases, Pearson correlation coefficient = 0.70, p = 0.02). Conclusions Bypass grafts can be assessed in a noninvasive fashion by using quantitative MR angiography. This imaging modality provides not only information regarding patency as shown by conventional angiography, but also a quantitative assessment of bypass function. In this study, a low or rapidly decreasing flow was indicative of a shrunken or stenotic graft. Quantitative MR angiography may provide an alternative to standard angiography for serial follow up of bypass grafts.

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Langer, David J., Daniel R. Lefton, Lauren Ostergren, Carolyn D. Brockington, Joon Song, Yasunari Niimi, Peeyush Bhargava, and Alejandro Berenstein. "Hemispheric Revascularization in the Setting of Carotid Occlusion and Subclavian Steal: A Diagnostic and Management Role for Quantitative Magnetic Resonance Angiography?" Neurosurgery 58, no. 3 (March 1, 2006): 528–33. http://dx.doi.org/10.1227/01.neu.0000197331.41985.15.

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Abstract OBJECTIVE: Advances in phase contrast magnetic resonance imaging have facilitated the noninvasive assessment of blood flow rates and flow direction in patients with complex cerebrovascular disorders. METHODS: We describe a case of right hemispheric hypoperfusion in which, on noninvasive assessment with quantitative magnetic resonance angiography, the patient was found to harbor an occult subclavian steal with flow reversal in the left vertebral artery. RESULTS: The presence of posterior communicating arteries noted on quantitative magnetic resonance angiography suggested that normalization of flow in the vertebral arteries by treating the subclavian occlusion could improve flow in the anterior circulation. Angiography confirmed the noninvasive findings, and the subclavian occlusion was treated with angioplasty and stenting. Postintervention quantitative magnetic resonance angiography documented quantitative improvement in right middle cerebral artery flow and restoration of antegrade flow in the left vertebral artery. CONCLUSION: This case illustrates the potential role of noninvasive assessment of blood flow rates and flow direction in the diagnosis, treatment planning, and follow-up of patients with complex cerebrovascular disease.

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Kim, D. H. "Evaluation of extracranial–intracranial bypass using quantitative magnetic resonance angiography." Yearbook of Neurology and Neurosurgery 2008 (January 2008): 226–27. http://dx.doi.org/10.1016/s0513-5117(08)79156-7.

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Watanuki, Atsushi, Hideaki Yoshino, Hiroshi Udagawa, Kenichi Yokoyama, Toshiaki Nitatori, Junichi Hachiya, and K. Ishikawa. "Quantitative evaluation of coronary stenosis by coronary magnetic resonance angiography." Heart and Vessels 15, no. 4 (July 2000): 159–66. http://dx.doi.org/10.1007/s003800070017.

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Amin-Hanjani, Sepideh, Ali Alaraj, Mateo Calderon-Arnulphi, Victor A. Aletich, Keith R. Thulborn, and Fady T. Charbel. "Detection of Intracranial In-Stent Restenosis Using Quantitative Magnetic Resonance Angiography." Stroke 41, no. 11 (November 2010): 2534–38. http://dx.doi.org/10.1161/strokeaha.110.594739.

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Brisman, Jonathan L. "Wingspan stenting of symptomatic extracranial vertebral artery stenosis and perioperative evaluation using quantitative magnetic resonance angiography: report of two cases." Neurosurgical Focus 24, no. 2 (February 2008): E14. http://dx.doi.org/10.3171/foc/2008/24/2/e14.

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✓The best management strategy for symptomatic vertebrobasilar ischemia is currently not well-defined. Noninvasive Optimal Vessel Analysis (NOVA, VasSol, Inc.) is computer software that, using quantitative magnetic resonance (MR) angiography technology, represents the only commercially available means of noninvasively measuring blood flow within the human vasculature. The author used quantitative MR angiography to study cerebral blood flow in 2 patients who underwent angioplasty and stenting for medically refractory extracranial cervical vertebral artery (VA) stenosis using the recently Food and Drug Administration–approved WingSpan stent (Boston Scientific, Target). WingSpan stents were successfully placed after balloon angioplasty in both patients without complications. At the 5-month clinical follow-up examination, 1 patient was symptom free and the other had had a possible transient ischemic attack without sequelae. The WingSpan stent may represent an alternative management scheme for symptomatic vertebrobasilar ischemia from extracranial VA stenosis. Quantitative MR angiography can readily measure blood flow in the vertebrobasilar system, and these values correlated with the angiographic outcomes in the 2 patients treated in the present study.

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Mavrogeni, Sophie, Athanassios Manginas, Emmanouil Papadakis, Stefanos Foussas, Marouso Douskou, Panagiotis Baras, Ioannis Seimenis, and Dennis Cokkinos. "Correlation Between Magnetic Resonance Angiography (MRA) and Quantitative Coronary Angiography (QCA) in Ectatic Coronary Vessels." Journal of Cardiovascular Magnetic Resonance 6, no. 1 (2004): 17–23. http://dx.doi.org/10.1081/jcmr-120027801.

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Amin-Hanjani, Sepideh, Amritha Singh, Hashem Rifai, Keith R. Thulborn, Ali Alaraj, Victor Aletich, and Fady T. Charbel. "Combined Direct and Indirect Bypass for Moyamoya." Neurosurgery 73, no. 6 (August 13, 2013): 962–68. http://dx.doi.org/10.1227/neu.0000000000000139.

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Abstract BACKGROUND: The optimal revascularization strategy for symptomatic adult moyamoya remains controversial. Whereas direct bypass offers immediate revascularization, indirect bypass can effectively induce collaterals over time. OBJECTIVE: Using angiography and quantitative magnetic resonance angiography, we examined the relative contributions of direct and indirect bypass in moyamoya patients after combined direct superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass and indirect encephaloduroarteriosynangiosis (EDAS). METHODS: A retrospective review of moyamoya patients undergoing combined STA-MCA bypass and EDAS was conducted, excluding pediatric patients and hemorrhagic presentation. Patients with quantitative magnetic resonance angiography measurements of the direct bypass immediately and > 6 months postoperatively were included. Angiographic follow-up, when available, was used to assess EDAS collaterals at similar time intervals. RESULTS: Of 16 hemispheres in 13 patients, 11 (69%) demonstrated a significant (> 50%) decline in direct bypass flow at > 6 months compared with baseline, averaging a drop from 99 ± 35 to12 ± 7 mL/min. Conversely, angiography in these hemispheres demonstrated prominent indirect collaterals, in concert with shrinkage of the STA graft. Decline in flow was apparent at a median of 9 months but was evident as early as 2 to 3 months. CONCLUSION: In this small cohort, a reciprocal relationship between direct STA bypass flow and indirect EDAS collaterals frequently occurred. This substantiates the notion that combined direct/indirect bypass can provide temporally complementary revascularization.

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Bahr-Hosseini, Mersedeh, Sophia F. Shakur, Sepideh Amin-Hanjani, Fady T. Charbel, and Ali Alaraj. "Angiographic Correlates of Cerebral Hemodynamic Changes With Diamox Challenge Assessed by Quantitative Magnetic Resonance Angiography." Stroke 47, no. 6 (June 2016): 1658–60. http://dx.doi.org/10.1161/strokeaha.116.013015.

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Petraikin, A. V., K. A. Sergunova, D. S. Semenov, E. S. Akhmad, S. Yu Kim, A. I. Gromov, and S. P. Morozov. "Dynamic Phantom for Flow Model in Magnetic Resonance Angiography." Medical Visualization, no. 6 (December 28, 2017): 130–39. http://dx.doi.org/10.24835/1607-0763-2017-6-130-139.

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Purpose. To develop phantom for flow modeling in magnetic resonance angiography (MRA): relative contrast assessment, accuracy of the linear velocity and volumetric flow, what improve accuracy of diagnostic in cardiac and neurosurgical clinics (quality assessment of blood and cerebrospinal fluid motion). To compare scanners of different manufactures in points of the MRA efficiency using the developed phantom.Materials and methods. The main part of dynamic phantom consists of a disc filled with agarose gel (for linear and volumetric velocity control) and silicone tubes for fluid flow modelling. MR study was performed at MRI units of two manufactures for comparing quantitative assessments of MRA sequences: 2DTOF, 3DTOF, and at three MRI units of one firm for estimated accuracy calibration curve calculating and linear velocity and volumetric flow determination for PC MRA. Phantom study well correlate with clinical MRA results.Results. Obtained phantom scanning results in 2DTOF, 3DTOF sequences allow for objective comparing two MRI units of different manufactures. For 2DTOF mode was showed more effective signal enhancement affected by TOF effect for scanner of manufacture 2, then manufacture 1: 8.86 ± 0.88 и 6.07 ± 0.03 corresponding. For 3DTOF was observed rather more inflow relative contrast affected by TOF effect for scanner of manufacture 1: 6.06 ± 0.47 and 3.17 ± 0.83 corresponding. However, for manufacture 1 was showed more significant signal suppression for fat tissue, which improve vasculature visualization. Accuracy linear velocity fluid flow measurement in 2DPC is equal to ±2σ = ±0,4 by five pixels for three scanners of one manufacture. Using developed phantom was modelled MRA effects in 3DPC and Time-SLIP modes.Conclusions. The developed dynamic phantom can be used for calibration tests in MRA. The case of MRI units of two manufactures were compared quantitative assessments of MRA sequences and analyzed methods of enhancement fluid flow signal.

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Carlson, Andrew P., Ali Alaraj, Sepideh Amin-Hanjani, Fady Charbel, and Victor Aletich. "Continued Concern About Parent Vessel Steno-Occlusive Progression With Onyx HD-500 and the Utility of Quantitative Magnetic Resonance Imaging in Serial Assessment." Neurosurgery 72, no. 3 (November 30, 2012): 341–52. http://dx.doi.org/10.1227/neu.0b013e31828048a3.

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Abstract BACKGROUND: Onyx HD-500 is a liquid embolic used to treat intracranial aneurysms. OBJECTIVE: To determine the incidence of parent vessel stenosis and the management strategy for these patients. METHODS: Medical records of patients treated with Onyx HD-500 between 2008 and 2011 were retrospectively reviewed. Clinical and radiographic evaluations were assessed. Quantitative magnetic resonance angiography and NOVA (VasSol, Chicago, Illinois) images were reviewed for patients in whom these examinations were acquired. RESULTS: Seventeen patients underwent treatment of unruptured internal carotid artery aneurysms. Three patients (17.6%) developed visual symptoms after the procedure: 2 permanent and 1 transient. Four patients (23.5%) developed delayed internal carotid artery stenosis at the 6- to 8-month follow-up angiography, despite a standard antiplatelet regimen with confirmed sensitivities to aspirin and clopidogrel. Quantitative magnetic resonance angiography was obtained in all patients with stenosis to guide treatment. One patient progressed to complete but asymptomatic internal carotid artery occlusion. The second and third patients had asymptomatic stenosis of 40% and 70%, respectively, both of which resolved on follow-up angiography. The fourth patient developed critical stenosis distal to the aneurysm neck. Quantitative magnetic resonance angiography demonstrated adequate flow in the first 3 patients and decreased flow in the fourth patient, necessitating angioplasty and stenting. Prolonged dual antiplatelet regimens were continued in 2 of the 4 patients, 1 with progression of stenosis and 1 with improvement of stenosis. CONCLUSION: We observed a higher rate of parent vessel steno-occlusive progression after aneurysm embolization with Onyx HD-500 than reported in the literature, despite overall low morbidity. Quantitative vessel flow imaging was useful in subsequent medical management and decision making to perform therapeutic angioplasty/stenting to preserve flow.

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Conway, Stafford A., Susana M. Bowling, James D. Geyer, Daniel C. Potts, Brett L. Clemons, and Camilo R. Gomez. "Quantitative Magnetic Resonance Angiography of the Cerebrovasculature in Physiologic and Pathologic States." Journal of Neuroimaging 18, no. 1 (January 2008): 34–37. http://dx.doi.org/10.1111/j.1552-6569.2007.00171.x.

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Prabhakaran, Shyam, Kalani R. Wells, Miral D. Jhaveri, and Demetrius K. Lopes. "Hemodynamic Changes Following Wingspan Stent Placement-A Quantitative Magnetic Resonance Angiography Study." Journal of Neuroimaging 21, no. 2 (March 24, 2011): e109-e113. http://dx.doi.org/10.1111/j.1552-6569.2009.00425.x.

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Greil, Gerald F., Thomas Boettger, Sabrina Germann, Bernhard Klumpp, Christof Baltes, Sebastian Kozerke, Anja Bialkowski, et al. "Quantitative assessment of ventricular function using three-dimensional SSFP magnetic resonance angiography." Journal of Magnetic Resonance Imaging 26, no. 2 (2007): 288–95. http://dx.doi.org/10.1002/jmri.20967.

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Khan, Nadia, Robert M. Lober, Lauren Ostergren, Jacob Petralia, Teresa Bell-Stephens, Ramon Navarro, Abdullah Feroze, and Gary K. Steinberg. "Measuring Cerebral Blood Flow in Moyamoya Angiopathy by Quantitative Magnetic Resonance Angiography Noninvasive Optimal Vessel Analysis." Neurosurgery 81, no. 6 (February 14, 2017): 921–27. http://dx.doi.org/10.1093/neuros/nyw122.

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Abstract BACKGROUND Moyamoya disease causes progressive occlusion of the supraclinoidal internal carotid artery, and middle, anterior, and less frequently the posterior cerebral arteries, carrying the risk of stroke. Blood flow is often partially reconstituted by compensatory moyamoya collaterals and sometimes the posterior circulation. Cerebral revascularization can further augment blood flow. These changes to blood flow within the cerebral vessels, however, are not well characterized. OBJECTIVE To evaluate blood flow changes resulting from the disease process and revascularization surgery using quantitative magnetic resonance angiography with noninvasive optimal vessel analysis (NOVA). METHODS We retrospectively analyzed 190 preoperative and postoperative imaging scans in 66 moyamoya patients after revascularization surgery. Images were analyzed for blood flow using NOVA and compared with preoperative angiographic staging and postoperative blood flow. Blood flow rates within superficial temporal artery grafts were compared based on angiographic evidence of patency. RESULTS Diseased vessels had lower blood flow, correlating with angiographic staging. Flow in posterior cererbal and basilar arteries increased with disease severity, particularly when both the anterior and middle cerebral arteries were occluded. Basilar artery flow and ipsilateral internal carotid artery flow decreased after surgery. Flow rates were different between angiographically robust and poor direct bypass grafts, as well as between robust and patent grafts. CONCLUSION Preoperative changes in cerebral vessel flow as measured by NOVA correlated with angiographic disease progression. NOVA demonstrated that preoperative augmentation of the posterior circulation decreased after surgery. This report is the first to quantify the shift in collateral supply from the posterior circulation to the bypass graft.

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Bae, Yun Jung, Cheolkyu Jung, Jae Hyoung Kim, Byung Se Choi, and Eunhee Kim. "Quantitative Magnetic Resonance Angiography in Internal Carotid Artery Occlusion with Primary Collateral Pathway." Journal of Stroke 17, no. 3 (September 30, 2015): 320–26. http://dx.doi.org/10.5853/jos.2015.17.3.320.

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Velikina, J. V., and A. A. Samsonov. "New Image Reconstruction Methods for Accelerated Quantitative Parameter Mapping and Magnetic Resonance Angiography." Journal of Physics: Conference Series 677 (February 16, 2016): 012002. http://dx.doi.org/10.1088/1742-6596/677/1/012002.

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Dirksen, Martijn S., Hildo J. Lamb, Rob van der Geest, and Albert de Roos. "Toward comparability of coronary magnetic resonance angiography: proposal for a standardized quantitative assessment." European Radiology 13, no. 10 (August 2, 2003): 2353–57. http://dx.doi.org/10.1007/s00330-003-2007-4.

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Manara, Renzo, Joseph Gabrieli, Valentina Citton, Filippo Ceccato, Silvia Rizzati, Giulia Bommarito, Chiara Briani, et al. "Intracranial internal carotid artery changes in acromegaly: a quantitative magnetic resonance angiography study." Pituitary 17, no. 5 (September 26, 2013): 414–22. http://dx.doi.org/10.1007/s11102-013-0516-y.

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Koenigkam-Santos, Marcel, Puneet Sharma, Bobby Kalb, John Carew, John N. Oshinski, and Diego Martin. "Lower extremities magnetic resonance angiography with blood pressure cuff compression: Quantitative dynamic analysis." Journal of Magnetic Resonance Imaging 29, no. 6 (June 2009): 1450–56. http://dx.doi.org/10.1002/jmri.21777.

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Andereggen, Lukas, Sepideh Amin-Hanjani, Marwan El-Koussy, Rajeev K. Verma, Kenya Yuki, Daniel Schoeni, Kety Hsieh, et al. "Quantitative magnetic resonance angiography as a potential predictor for cerebral hyperperfusion syndrome: a preliminary study." Journal of Neurosurgery 128, no. 4 (April 2018): 1006–14. http://dx.doi.org/10.3171/2016.11.jns161033.

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OBJECTIVECerebral hyperperfusion syndrome (CHS) is a rare but devastating complication of carotid endarterectomy (CEA). This study sought to determine whether quantitative hemodynamic assessment using MR angiography can stratify CHS risk.METHODSIn this prospective trial, patients with internal carotid artery (ICA) stenosis were randomly selected for pre- and postoperative quantitative phase-contrast MR angiography (QMRA). Assessment was standardized according to a protocol and included Doppler/duplex sonography, MRI, and/or CT angiography and QMRA of the intra- and extracranial supplying arteries of the brain. Clinical and radiological data were analyzed to identify CHS risk factors.RESULTSTwenty-five of 153 patients who underwent CEA for ICA stenosis were randomly selected for pre- and postoperative QMRA. QMRA data showed a 2.2-fold postoperative increase in blood flow in the operated ICA (p < 0.001) and a 1.3-fold increase in the ipsilateral middle cerebral artery (MCA) (p = 0.01). Four patients had clinically manifested CHS. The mean flow increases in the patients with CHS were significantly higher than in the patients without CHS, both in the ICA and MCA (p < 0.001). Female sex and a low preoperative diastolic blood pressure were the clearest clinical risk factors for CHS, whereas the flow differences and absolute postoperative flow values in the ipsilateral ICA and MCA were identified as potential radiological predictors for CHS.CONCLUSIONSCerebral blood flow in the ipsilateral ICA and MCA as assessed by QMRA significantly increased after CEA. Higher mean flow differences in ICA and MCA were associated with the development of CHS. QMRA might have the potential to become a noninvasive, operator-independent screening tool for identifying patients at risk for CHS.

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Amin-Hanjani, Sepideh, Xinjian Du, Meide Zhao, Katherine Walsh, Tim W. Malisch, and Fady T. Charbel. "Use of Quantitative Magnetic Resonance Angiography to Stratify Stroke Risk in Symptomatic Vertebrobasilar Disease." Stroke 36, no. 6 (June 2005): 1140–45. http://dx.doi.org/10.1161/01.str.0000166195.63276.7c.

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Weintraub, Michael I., and Andre Khoury. "Use of Quantitative Magnetic Resonance Angiography to Stratify Stroke Risk in Symptomatic Vertebrobasilar Disease." Stroke 36, no. 11 (November 2005): 2341–42. http://dx.doi.org/10.1161/01.str.0000185724.55127.6e.

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Eskandari, M. K. "Use of Quantitative Magnetic Resonance Angiography to Stratify Stroke Risk in Symptomatic Vertebrobasilar Disease." Yearbook of Vascular Surgery 2007 (January 2007): 290–91. http://dx.doi.org/10.1016/s0749-4041(08)70560-8.

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Amin-Hanjani, S., X. Du, and M. Zhao. "Use of Quantitative Magnetic Resonance Angiography To Stratify Stroke Risk in Symptomatic Vertebrobasilar Disease." Journal of Vascular Surgery 42, no. 3 (September 2005): 591. http://dx.doi.org/10.1016/j.jvs.2005.07.026.

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Amin-Hanjani, S., X. Du, and M. Zhao. "Use of Quantitative Magnetic Resonance Angiography to Stratify Stroke Risk in Symptomatic Vertebrobasilar Disease." Journal of Vascular Surgery 43, no. 1 (January 2006): 197. http://dx.doi.org/10.1016/j.jvs.2005.12.026.

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Paetsch, Ingo, Daniela Föll, Adam Kaluza, Roger Luechinger, Matthias Stuber, Axel Bornstedt, Andreas Wahl, Eckart Fleck, and Eike Nagel. "Magnetic resonance stress tagging in ischemic heart disease." American Journal of Physiology-Heart and Circulatory Physiology 288, no. 6 (June 2005): H2708—H2714. http://dx.doi.org/10.1152/ajpheart.01017.2003.

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High-dose dobutamine magnetic resonance stress testing has been shown to be superior to dobutamine stress echocardiography for diagnosis of coronary artery disease (CAD). We determined the feasibility of quantitative myocardial tagging during low- and high-dose dobutamine stress and tested the ability of global systolic and diastolic quantitative parameters to identify patients with significant CAD. Twenty-five patients suspected of having significant CAD were examined with a standard high-dose dobutamine/atropine stress magnetic resonance protocol (1.5-T scanner, Philips). All patients underwent invasive coronary angiography as the standard of reference for the presence ( n = 13) or absence ( n = 12) of significant CAD. During low-dose dobutamine stress, systolic (circumferential shortening, systolic rotation, and systolic rotation velocity) and diastolic (velocity of circumferential lengthening and diastolic rotation velocity) parameters changed significantly in patients without CAD (all P < 0.05 vs. rest) but not in patients with CAD. Identification of patients without and with CAD during low-dose stress was possible using the diastolic parameter of “time to peak untwist.” At high-dose stress, none of the global systolic or diastolic parameters showed the potential to identify the presence of significant CAD. With myocardial tagging, a quantitative analysis of systolic and diastolic function was feasible during low- and high-dose dobutamine stress. In our study, the diastolic parameter of time to peak untwist as assessed during low-dose dobutamine stress was the most promising global parameter for identification of patients with significant CAD. Thus quantitative myocardial tagging may become a tool that reduces the need for high-dose dobutamine stress.

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Yang, Yuan, Le He, Suhua Miao, Rongsong Zhou, Yuqi Zhang, and Yu Ma. "Quantitative analysis of cerebrovascular characteristics of Parkinson’s disease treated with acupuncture based on magnetic resonance angiography." Brain Science Advances 7, no. 2 (June 2021): 141–54. http://dx.doi.org/10.26599/bsa.2021.9050015.

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Background: Acupuncture has become an important alternative clinical treatment for Parkinson’s disease (PD), but its efficacy and the underlying mechanisms remain debatable. Using a newly developed magnetic resonance angiography (MRA) method that has higher sensitivity for smaller and distal vessels and a novel tool that can trace vessels and extract vascular features, the immediate effects of acupuncture on intracranial vessels and blood flow in patients with PD as well as correlations with clinical outcomes were quantitatively evaluated. Methods: Fifteen PD patients received acupuncture at the Dazhui and Fengchi acupoint positions. MRA was performed before and after 30 min of treatment. The cerebral blood flow (CBF) and the length, volume, diameter, and signal intensity of the intracranial internal carotid artery (ICA) and middle cerebral artery (MCA) were measured. The Unified Parkinson’s Disease Rating Scale part III (UPDRS-III) and Visual Analogue Scale (VAS) were used to evaluate the motor symptoms and the subjective feelings of discomfort. Results: Acupuncture significantly reduced UPDRS-III and VAS scores. No significant changes were noted in the overall CBF before and after treatment. However, there was a significant extension effect on the length of the intracranial ICA and MCA and the distal MCA, and a significant increase in the number of branches of the MCA was found. Although acupuncture tended to increase the total volume of the intracranial ICA and the volume of the MCA, no statistical significance was reached. The total intensity was not altered, but the intensity and diameter of the M1 segment were significantly increased, whereas the intensity of the MCA was decreased. A positive correlation between M1 intensity changes and UPDRS-III changes was found. Conclusions: Angiographic evaluation suggested that acupuncture had a significant effect on intracranial blood vessels, which is one possible mechanism for acupuncture improving the motor symptoms of PD.

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Leliefeld, Paul H., Rob H. J. M. Gooskens, Koen L. Vincken, Lino M. P. Ramos, Jeroen van der Grond, Cees A. F. Tulleken, L. Jaap Kappelle, and Patrick W. Hanlo. "Magnetic resonance imaging for quantitative flow measurement in infants with hydrocephalus: a prospective study." Journal of Neurosurgery: Pediatrics 2, no. 3 (September 2008): 163–70. http://dx.doi.org/10.3171/ped/2008/2/9/163.

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Object Raised intracranial pressure (ICP) that is associated with hydrocephalus may lead to alterations in cerebral hemodynamics and ischemic changes in the brain. In infants with hydrocephalus, defining the right moment for surgical intervention based on clinical signs alone can sometimes be a difficult task. Clinical signs of raised ICP are known to be unreliable and sometimes even misleading. Furthermore, when sutures are closed, ICP does not always correlate with the size of the ventricles or with the clinical signs or symptoms. In this study the authors investigated whether cerebral blood flow (CBF) can be measured by using quantitative MR angiography in infants with progressive hydrocephalus. In addition, the authors investigated the relationship between CBF and ICP, before and after cerebrospinal fluid (CSF) diversion. Methods Fifteen infants with progressive hydrocephalus (age range 1 day–7 months) were examined. All patients underwent anterior fontanel pressure measurement, MR angiography, and mean arterial blood pressure measurements before and after CSF diversion. Brain volume was measured to compensate for the physiological increase in CBF during brain maturation in infants. Results The mean preoperative ICP was 19.1 ± 8.4 cm H2O (± standard deviation). The mean postoperative ICP was 6.7 ± 4.0 cm H2O (p < 0.005). The mean preoperative CBF was 25.7 ± 11.3 ml/100 cm3 brain/min. After CSF diversion, CBF increased to 50.1 ± 12.1 ml/100 cm3 brain/min (p < 0.005). The mean arterial blood pressure did not change after surgical intervention. Conclusions Magnetic resonance imaging can be used to measure CBF in infants with hydrocephalus. Raised ICP was related to a decrease in CBF. After CSF diversion, CBF and ICP improved to values within the normal range.

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Kim, Tackeun, Jae Seung Bang, O.-Ki Kwon, Gyojun Hwang, Jeong Eun Kim, Hyun-Seung Kang, Won-Sang Cho, Cheolkyu Jung, and Chang Wan Oh. "Hemodynamic Changes after Unilateral Revascularization for Moyamoya Disease: Serial Assessment by Quantitative Magnetic Resonance Angiography." Neurosurgery 81, no. 1 (January 2, 2017): 111–19. http://dx.doi.org/10.1093/neuros/nyw035.

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Abstract BACKGROUND: Ultrasonic flow meters and quantitative magnetic resonance angiography quantitatively assess flow during hemodynamic evaluation of cerebral ischemia. Although their reliability and reproducibility have been verified, their clinical impact in moyamoya disease has rarely been reported. OBJECTIVE: To investigate flow measurement outcomes in moyamoya disease patients pre- and postoperatively through a retrospective observational study. METHODS: We evaluated 41 patients undergoing their first revascularization surgery who were followed ≥6 mo. Hemodynamic parameters were recorded preoperatively, at 1 and 6 mo postoperatively, and at the last follow-up. Demographic factors, Suzuki stage, and stroke development were also analyzed. RESULTS: Patients’ median age was 37 yr (interquartile range [IQR], 27-43), and 16 (39.0%) patients were men. During follow-up, 9 (22.0%) patients experienced postoperative stroke (4 major strokes). Hemodynamic status was improved in 34 (82.9%) patients at the 6-mo follow-up. Median intraoperative flow was 41 mL/min (IQR, 25-59). Bypass flow peaked at 6 mo (median, 67 mL/min; IQR, 35-99). At the 1- and 6-mo follow-ups, ipsilateral hemispheric flow was significantly increased. The median proportion of posterior circulation at 6 mo was 44.4%, significantly lower than the preoperative proportion (50.1%). Abundant intraoperative bypass flow was associated with hemodynamic improvement, while low contralateral hemispheric flow was related with immediate postoperative ischemic stroke. CONCLUSION: Ipsilateral hemispheric flow was increased during 6-mo follow-up, and posterior circulation flow burden was diminished. Abundant intraoperative bypass flow was associated with postoperative hemodynamic improvement. Low preoperative contralateral hemispheric flow was related with immediate postoperative ischemic stroke.

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Prabhakaran, Shyam, Lakshmi Warrior, Kalani R. Wells, Miral D. Jhaveri, Michael Chen, and Demetrius K. Lopes. "The Utility of Quantitative Magnetic Resonance Angiography in the Assessment of Intracranial In-Stent Stenosis." Stroke 40, no. 3 (March 2009): 991–93. http://dx.doi.org/10.1161/strokeaha.108.522391.

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Ruland, Sean, Aiesha Ahmed, Kurian Thomas, Meide Zhao, Sepideh Amin-Hanjani, Xinjian Du, and Fady T. Charbel. "Leptomeningeal Collateral Volume Flow Assessed by Quantitative Magnetic Resonance Angiography in Large-Vessel Cerebrovascular Disease." Journal of Neuroimaging 19, no. 1 (January 2009): 27–30. http://dx.doi.org/10.1111/j.1552-6569.2008.00249.x.

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Esfahani, Darian R., Dilip Pandey, Xinjian Du, Linda Rose-Finnell, Fady T. Charbel, Colin P. Derdeyn, and Sepideh Amin-Hanjani. "Cost-Effectiveness of Quantitative Magnetic Resonance Angiography Screening and Submaximal Angioplasty for Symptomatic Vertebrobasilar Disease." Stroke 49, no. 8 (August 2018): 1953–59. http://dx.doi.org/10.1161/strokeaha.118.022339.

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Hu, Yong-Sin, Cheng-Chia Lee, Hsiu-Mei Wu, Huai-Che Yang, Te-Ming Lin, Chao-Bao Luo, Wan-Yuo Guo, Wen-Yuh Chung, and Chung-Jung Lin. "Stagnant Venous Outflow Predicts Brain Arteriovenous Malformation Obliteration After Gamma Knife Radiosurgery Without Prior Intervention." Neurosurgery 87, no. 2 (December 3, 2019): 338–47. http://dx.doi.org/10.1093/neuros/nyz507.

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Abstract BACKGROUND Gamma Knife radiosurgery (GKRS) obliterates 65% to 82% of brain arteriovenous malformations (BAVMs). OBJECTIVE To explore the impact of hemodynamics on GKRS outcomes. METHODS We retrospectively (2011-2017) included 98 patients with BAVMs who had received GKRS alone. Two evaluators, blinded to the outcomes, analyzed the pre-GKRS angiography and magnetic resonance images to obtain the morphological characteristics and quantitative digital subtraction angiography (QDSA) parameters. The venous stasis index was defined as the inflow gradient divided by the absolute value of the outflow gradient. Patients’ follow-up magnetic resonance or digital subtraction angiography images were evaluated for the presence of complete obliteration (CO). Cox regression and Kaplan–Meier analyses were conducted to determine the correlations between the parameters and outcomes. RESULTS Among the 98 patients, 63 (63.4%) achieved CO after GKRS at a median latency period of 31 mo. In multivariable analyses with adjustments for age and sex, increased BAVM volume (hazard ratio (HR) 0.949, P = .022) was an independent characteristic predictor, and venous stenosis (HR 2.595, P = .009), venous rerouting (HR 0.375, P = .022), and larger stasis index (HR 1.227, P = .025) were independent angiographic predictors of CO. BAVMs with a stasis index of >1.71 had a higher 36-mo probability of CO than those with a stasis index of ≤1.71 (61.1% vs 26.7%, P < .001). CONCLUSION BAVMs with a larger stasis index, indicating more stagnant venous outflow, may predict obliteration after GKRS. QDSA analysis may help in predicting BAVM treatment outcomes and making therapeutic decisions.

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Amin-Hanjani, Sepideh, Alfred P. See, Xinjian Du, Linda Rose-Finnell, Dilip K. Pandey, Yi-Fan Chen, Mitchell S. V. Elkind, et al. "Natural History of Hemodynamics in Vertebrobasilar Disease." Stroke 51, no. 11 (November 2020): 3295–301. http://dx.doi.org/10.1161/strokeaha.120.029909.

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Background and Purpose: The role of regional hypoperfusion as a contributor to stroke risk in atherosclerotic vertebrobasilar disease has recently been confirmed by the observational VERiTAS (Vertebrobasilar Flow Evaluation and Risk of Transient Ischemic Attack and Stroke) Study. We examined the stability of hemodynamic status over time and its relationship to stroke risk in patients from this prospective cohort. Methods: VERiTAS enrolled patients with recently symptomatic ≥50% atherosclerotic stenosis/occlusion of vertebral and/or basilar arteries. Large vessel flow in the vertebrobasilar territory was assessed using quantitative magnetic resonance angiography, and patients were designated as low or normal flow based on distal territory regional flow, incorporating collateral capacity. Patients underwent standard medical management and follow-up for primary outcome event of vertebrobasilar territory stroke. Quantitative magnetic resonance angiography imaging was repeated at 6, 12, and 24 months. Flow status over time was examined relative to baseline and relative to subsequent stroke risk using a cause-specific proportional hazard model, with flow status treated as a time-varying covariate. Mean blood pressure was examined to assess for association with changes in flow status. Results: Over 19±8 months of follow-up, 132 follow-up quantitative magnetic resonance angiography studies were performed in 58 of the 72 enrolled patients. Of the 13 patients with serial imaging who had low flow at baseline, 7 (54%) had improvement to normal flow at the last follow-up. Of the 45 patients who had normal flow at baseline, 3 (7%) converted to low flow at the last follow-up. The mean blood pressure did not differ in patients with or without changes in flow status. The time-varying flow status remained a strong predictor of subsequent stroke (hazard ratio, 10.3 [95% CI, 2.2–48.7]). Conclusions: There is potential both for improvement and worsening of hemodynamics in patients with atherosclerotic vertebrobasilar disease. Flow status, both at baseline and over time, is a risk factor for subsequent stroke, thus serving as an important prognostic marker. Registration: URL: https://clinicaltrials.gov . Unique identifier: NCT00590980.

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Shakur, Sophia F., Denise Brunozzi, Ahmed E. Hussein, Andreas Linninger, Chih-Yang Hsu, Fady T. Charbel, and Ali Alaraj. "Validation of cerebral arteriovenous malformation hemodynamics assessed by DSA using quantitative magnetic resonance angiography: preliminary study." Journal of NeuroInterventional Surgery 10, no. 2 (February 24, 2017): 156–61. http://dx.doi.org/10.1136/neurintsurg-2017-012991.

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BackgroundThe hemodynamic evaluation of cerebral arteriovenous malformations (AVMs) using DSA has not been validated against true flow measurements.ObjectiveTo validate AVM hemodynamics assessed by DSA using quantitative magnetic resonance angiography (QMRA).Materials and methodsPatients seen at our institution between 2007 and 2016 with a supratentorial AVM and DSA and QMRA obtained before any treatment were retrospectively reviewed. DSA assessment of AVM flow comprised AVM arterial-to-venous time (A-Vt) and iFlow transit time. A-Vt was defined as the difference between peak contrast intensity in the cavernous internal carotid artery and peak contrast intensity in the draining vein. iFlow transit times were determined using syngo iFlow software. A-Vt and iFlow transit times were correlated with total AVM flow measured using QMRA and AVM angioarchitectural and clinical features.Results33 patients (mean age 33 years) were included. Nine patients presented with hemorrhage. Mean AVM volume was 9.8 mL (range 0.3–57.7 mL). Both A-Vt (r=−0.47, p=0.01) and iFlow (r=−0.44, p=0.01) correlated significantly with total AVM flow. iFlow transit time was significantly shorter in patients who presented with seizure but A-Vt and iFlow did not vary with other AVM angioarchitectural features such as venous stenosis or hemorrhagic presentation.ConclusionsA-Vt and iFlow transit times on DSA correlate with cerebral AVM flow measured using QMRA. Thus, these parameters may be used to indirectly estimate AVM flow before and after embolization during angiography in real time.

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Bauer, Andrew M., Sepideh Amin-Hanjani, Ali Alaraj, and Fady T. Charbel. "Quantitative Magnetic Resonance Angiography in the Evaluation of the Subclavian Steal Syndrome: Report of 5 Patients." Journal of Neuroimaging 19, no. 3 (July 2009): 250–52. http://dx.doi.org/10.1111/j.1552-6569.2008.00297.x.

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Fitzgerald, Tamara N., Akihito Muto, Fabio Akimaro Kudo, Jose Mario Pimiento, Robert Todd Constable, and Alan Dardik. "Emerging Vascular Applications of Magnetic Resonance Imaging: A Picture is Worth More than a Thousand Words." Vascular 14, no. 6 (November 2006): 366–71. http://dx.doi.org/10.2310/6670.2006.00062.

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Vascular applications of magnetic resonance (MR) imaging are reviewed, with emphasis on algorithms that use nonpictorial information contained in the MR data set. Current clinical vascular practice generally limits use of MR angiography and three-dimensional vessel images to qualitative pictorial rendering without routinely using the available quantitative information contained within the MR data. This review is dedicated to recent advances that include characterization of vessel histology, assessment of carotid plaque vulnerability, characterization of blood flow dynamics, quantitative analysis of disease severity, and prediction of vascular intervention outcome. Examples from histologic preparation, in vitro and in vivo experiments, are discussed, with an emphasis on potential clinical applications and advances in acquisition technology.

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Starke, Robert M., Mark Chwajol, Daniel Lefton, Chandranath Sen, Alejandro Berenstein, and David J. Langer. "OCCIPITAL ARTERY-TO-POSTERIOR INFERIOR CEREBELLAR ARTERY BYPASS FOR TREATMENT OF BILATERAL VERTEBRAL ARTERY OCCLUSION: THE ROLE OF QUANTITATIVE MAGNETIC RESONANCE ANGIOGRAPHY NONINVASIVE OPTIMAL VESSEL ANALYSIS." Neurosurgery 64, no. 4 (April 1, 2009): E779—E781. http://dx.doi.org/10.1227/01.neu.0000339351.65061.d6.

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Abstract OBJECTIVE Patients with partial or complete bilateral vertebral artery occlusion often present with signs and symptoms of transient ischemic attacks or infarction. Advances in phase contrast magnetic resonance imaging have led to noninvasive assessment of volumetric blood flow rates and direction that help in the workup and management of these patients. CLINICAL PRESENTATION We present the case of a patient with symptoms of vertebrobasilar insufficiency without previous transient ischemic attacks or stroke. Quantitative magnetic resonance angiography (QMRA) demonstrated bilateral vertebral artery occlusion with reversal of flow in the basilar and vertebral arteries to the level of the posterior inferior cerebellar arteries bilaterally. A prominent right posterior communicating artery filled the basilar artery and proximal vertebral arteries. INTERVENTION The presence of reversal and diminished flow in the basilar and vertebral arteries suggested that occipital artery-to-posterior inferior cerebellar artery bypass would improve posterior circulation, relieve symptoms, and reduce the risk of infarction. Postoperative QMRA and angiography confirmed revascularization, and QMRA confirmed correction of blood flow direction. CONCLUSION This case illustrates the potential of QMRA as part of a comprehensive cerebrovascular assessment, operative planning, and follow-up of patients with vertebrobasilar insufficiency.

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Erickson, Bradley J., Brian A. Cole, and John Huston. "Semiautomated Quantitation of Carotid Artery Stenosis in Gadolinium-Bolus Magnetic Resonance Angiography." Journal of Digital Imaging 15, no. 2 (June 1, 2002): 69–77. http://dx.doi.org/10.1007/s10278-002-0006-7.

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Chang, Kwang-Hwa, Yuan-Hao Lee, Chia-Yuen Chen, Ming-Fang Lin, Ying Chin Lin, Jyh-Horng Chen, and Wing P. Chan. "Inter- and Intra-Rater Reliability of Individual Cerebral Blood Flow Measured by Quantitative Vessel-Flow Phase-Contrast MRI." Journal of Clinical Medicine 9, no. 10 (September 25, 2020): 3099. http://dx.doi.org/10.3390/jcm9103099.

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Vessel flow quantification by two-dimensional (2D) phase-contrast magnetic resonance imaging (PC-MRI) using a three-dimensional (3D) magnetic resonance angiography (MRA) model to measure cerebral blood flow has unclear analytical reliability. The present study aimed to determine the inter- and intra-rater reliability of quantitative vessel-flow PC-MRI and potential factors influencing its consistency. We prospectively recruited 30 Asian participants (aged 20–90 years; 16 women; 22 healthy and 8 stroke patients) for performing 1.5-T MR equipped with a head coil. Each participant was first scanned for time-of-flight magnetic resonance angiography (TOF-MRA) images for localization of intracranial arteries. The 2D PC-MRI for each cerebral artery (total 13 arteries in fixed order) was performed twice by two well-trained operators in optimal position. Using the same 3D MRA as a map and facilitated with the non-invasive optimal vessel analysis (NOVA) system, each scan was taken on a plane perpendicular to the target artery. Two consecutive full 13-artery scans were performed at least 15 min apart after participants were removed from the scanner table and then repositioned. A total of four PC flow images obtained from each target artery were transmitted to a workstation facilitated with the NOVA system. Flow data were calculated semi-automatically by the NOVA system after a few simple steps. Two-way mixed-effect models and standard errors of measurements were used. In 13 cerebral arteries, repeatability, using the intra-rater estimate expressed as the average-measures intraclass correlation coefficient, ranged from 0.641 to 0.954, and reproducibility, using the inter-rater estimate, ranged from 0.672 to 0.977. Except in the middle cerebral artery and the distal segment of the anterior cerebral artery, repeatability and reproducibility were excellent (intraclass correlation coefficient exceeded 0.8). The use of quantitative vessel-flow PC-MRI is a precise means to measure blood flow in most target cerebral arteries. This was evidenced by inter-rater and intra-rater correlations that were good/excellent, indicating good reproducibility and repeatability.

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Li, Daniel, Meide Zhao, Sepideh Amin-Hanjani, Robert Kufahl, Xinjian Du, Victor A. Aletich, Ali Alaraj, Jianmin Li, and Fady T. Charbel. "110 Patient-Specific Cerebral Regional Blood Flow Model Using Quantitative Magnetic Resonance Angiography to Predict Stump Pressure." Neurosurgery 65, CN_suppl_1 (August 16, 2018): 83–84. http://dx.doi.org/10.1093/neuros/nyy303.110.

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Yagi, Y., E. Keller, R. Lewandowski, N. Chatterjee, R. Salem, J. Carr, T. Carroll, and J. Collins. "Predicting HCC treatment response to Y-90 radioembolization by quantitative perfusion using contrast-enhanced magnetic resonance angiography." Journal of Vascular and Interventional Radiology 27, no. 3 (March 2016): S66. http://dx.doi.org/10.1016/j.jvir.2015.12.179.

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Haraguchi, K., K. Houkin, I. Koyanagi, T. Nonaka, and T. Baba. "Evaluation of Carotid Plaque Composition by Computed Tomography Angiography and Black Blood Magnetic Resonance Image." Interventional Neuroradiology 14, no. 1 (March 2008): 39–43. http://dx.doi.org/10.1177/159101990801400105.

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The purpose of this study was to evaluate the composition of a carotid plaque quantitatively by computed tomography (CT) angiography and qualitatively by black blood magnetic resonance imaging (MRI). Thirty-eight patients with high-grade carotid artery stenosis were included in this study. Ultrasonography, CT angiography and black blood MRI of the cervical carotid artery were performed, and the CT number was measured in Hounsfield units (HU). The average CT number of the 15 unstable plaques (39.5%) was 27.7 ± 7.5 HU and that of the 23 stable plaques (60.5%) was 60.4 ± 20.8 HU (p <0.0001). In the 23 patients with stable plaque, 21 demonstrated isointensity in T1 and T2 in the black blood MRI (p <0.0001). By using CT angiography and MRI, precise images of the pathology of the carotid arterial wall can be obtained. It is possible to evaluate the components of a carotid artery plaque with high reliability by quantification of the CT number in CT angiography and performing black blood MRI as well as in carotid ultrasonography.

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Brunozzi, Denise, Ahmed E. Hussein, Sophia F. Shakur, Andreas Linninger, Chih-Yang Hsu, Fady T. Charbel, and Ali Alaraj. "Contrast Time-Density Time on Digital Subtraction Angiography Correlates With Cerebral Arteriovenous Malformation Flow Measured by Quantitative Magnetic Resonance Angiography, Angioarchitecture, and Hemorrhage." Neurosurgery 83, no. 2 (July 6, 2017): 210–16. http://dx.doi.org/10.1093/neuros/nyx351.

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Abstract BACKGROUND Digital subtraction angiography (DSA) currently provides angioarchitectural features of cerebral arteriovenous malformations (AVMs) but its role in the hemodynamic evaluation of AVMs is poorly understood. OBJECTIVE To assess contrast time-density time (TT) on DSA relative to AVM flow measured using quantitative magnetic resonance angiography (QMRA). METHODS Patients seen at our institution between 2007 and 2014 with a supratentorial AVM and DSA and QMRA obtained prior to any treatment were retrospectively reviewed. Regions of interest were selected on the draining veins at the point closest to the nidus. TT on DSA was defined as time needed for contrast to change image intensity from 10% to 100%, 100% to 10%, and 25% to 25%. TT was correlated to AVM total flow, angioarchitectural features, and hemorrhage. RESULTS Twenty-eight patients (mean age 35.6 yr) were included. Six patients presented with hemorrhage. Mean AVM volume was 11.42 mL (range 0.3-57.7 mL). Higher total AVM flow significantly correlated with shorter TT100%-10% and TT25%-25% (P = .02, .02, respectively). Presence of venous stenosis correlated significantly with shorter TT100%-10% (P = .04) and TT25%-25% (P = .04). AVMs with a single draining vein exhibited longer TT25%-25% compared to those with multiple draining veins (P = .04). Ruptured AVMs had significantly shorter TT10%-100% compared to unruptured AVMs (P = .05). CONCLUSION TT on DSA correlates with cerebral AVM flow measured using QMRA and with AVM angioarchitecture and hemorrhagic presentation. Thus, TT may be used to indirectly estimate AVM flow during angiography in real-time and may also be an indicator of important AVM characteristics associated with outflow resistance and increased rupture risk, such as venous stenosis.

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Fasler, David A., Michael Ingrisch, Daniel Nanz, Sabine Weckbach, Diego Kyburz, Dorothee R. Fischer, Roman Guggenberger, and Gustav Andreisek. "Rheumatoid cervical pannus: feasibility of volume and perfusion quantification using dynamic contrast enhanced time resolved MRI." Acta Radiologica 61, no. 2 (June 6, 2019): 227–35. http://dx.doi.org/10.1177/0284185119854200.

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Background Dynamic contrast-enhanced magnetic resonance imaging has the potential to show disease activity of rheumatoid arthritis even in complex anatomic areas as the atlantodental region. Purpose To demonstrate the technical feasibility of measuring synovial volume and perfusion characteristics with dynamic contrast-enhanced magnetic resonance imaging of the atlantodental region in patients with rheumatoid arthritis. Material and Methods Ten patients with rheumatoid arthritis and cervical spine involvement underwent dynamic contrast-enhanced magnetic resonance imaging of the cervical spine at 1.5 T. For each patient, 80 3D datasets were acquired using the commercialized Time Resolved Imaging of Contrast KineticS (TRICKS) sequence. Volumes of synovia with active synovitis on anatomical and parametric images were segmented. Synovial tissue perfusion parameters, namely plasma flow (Fp), relative plasma volume (vp), and the permeability-surface area product (PS), were calculated using a two-compartment uptake model. Statistical analysis included calculation of intra- and inter-reader agreement and a correlation of perfusion parameters with Outcome Measures in Rheumatology Clinical Trials (OMERACT) criteria. Results Dynamic contrast-enhanced magnetic resonance imaging as well as quantification of volume and perfusion characteristics of synovia was successful in most patients (80%). Intra- and inter-reader agreement was excellent (0.89–0.99). There was a positive correlation between OMERACT score and the permeability-surface product. Conclusion Dynamic contrast-enhanced magnetic resonance imaging using a 4D angiography sequence for the atlantodental region in patients with rheumatoid arthritis for quantitative and qualitative assessment of synovial volume and perfusion characteristics is technically feasible.

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Chen, Yongsheng, Saifeng Liu, Sagar Buch, Jiani Hu, Yan Kang, and E. Mark Haacke. "An interleaved sequence for simultaneous magnetic resonance angiography (MRA), susceptibility weighted imaging (SWI) and quantitative susceptibility mapping (QSM)." Magnetic Resonance Imaging 47 (April 2018): 1–6. http://dx.doi.org/10.1016/j.mri.2017.11.005.

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Caputi, Luigi, Francesco Ghielmetti, Giuseppe Faragò, Fabio Longaretti, Massimo Lamperti, Gian Paolo Anzola, Maria Rita Carriero, et al. "Cerebrovascular reactivity by quantitative magnetic resonance angiography with a co 2 challenge. Validation as a new imaging biomarker." European Journal of Radiology 83, no. 6 (June 2014): 1005–10. http://dx.doi.org/10.1016/j.ejrad.2014.03.001.

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Journal articles on the topic 'Quantitative magnetic resonance angiography'

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