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Tomography perfusion

Søren Hess, Evan C Frary, Oke Gerke, Poul Henning Madsen
Pulmonary embolism (PE) is a common, ubiquitous, and potentially lethal disease. As symptoms and clinical findings are notoriously nonspecific, diagnostic imaging is essential to avoid undertreatment as well as overtreatment. Controversies remain regarding first-line imaging in suspected PE. The two main contemporary contenders are ventilation/perfusion scintigraphy with single-photon emission computed tomography (V/Q SPECT) with or without additional low-dose CT (SPECT/CT) and CT angiography (CTA). We present our results from a systematic review and meta-analysis of the diagnostic performances of these modalities: V/Q SPECT, V/Q SPECT/CT, and CTA are all viable options, but we consider V/Q SPECT/CT to be superior in most clinical settings with better overall diagnostic performance, that is, pooled sensitivities (97...
October 20, 2016: Seminars in Thrombosis and Hemostasis
Nobuhiro Yada, Hideo Onishi, Masahiro Miyai, Kentarou Ozasa, Masuo Haramoto, Yasushi Yamamoto, Shuhei Yamaguchi, Hajime Kitagaki
PURPOSE: This study aimed to verify the resolution recovery for each collimator in the brain perfusion image. METHOD: To verify the effect of the resolution recovery for each collimator, we evaluated via the three-dimensional brain phantom (phantom) and the normal brain perfusion single photon emission computed tomography (SPECT) data. These data were reconstructed using the three-dimensional ordered subset expectation maximization method (3D-OSEM) (Evolution for bone(TM)) that was performed with scatter correction, attenuation correction, and resolution recovery (RR)...
2016: Nihon Hoshasen Gijutsu Gakkai Zasshi
M C Burg, P Lunkenheimer, P Niederer, C Brune, K Redmann, M Smerup, U Spiegel, F Becker, D Maintz, W Heindel, R H Anderson
Purpose: There are ongoing arguments as to how cardiomyocytes are aggregated together within the ventricular walls. We used pneumatic distension through the coronary arteries to exaggerate the gaps between the aggregated cardiomyocytes, analyzing the pattern revealed using computed tomography, and validating our findings by histology. Methods: We distended 10 porcine hearts, arresting 4 in diastole by infusion of cardioplegic solutions, and 4 in systole by injection of barium chloride. Mural architecture was revealed by computed tomography, measuring also the angulations of the long chains of cardiomyocytes...
November 2016: RöFo: Fortschritte Auf Dem Gebiete der Röntgenstrahlen und der Nuklearmedizin
Richard F Spaide
PURPOSE: To investigate the structural optical coherence tomography and related microvascular flow characteristics in eyes with retinal vasculitis. METHODS: Regions involved with perivascular infiltration in eyes with retinal vasculitis, but no evidence of large vessel occlusion were evaluated with optical coherence tomography (OCT), OCT angiography, and fluorescein angiography. RESULTS: Ten eyes of 5 patients with a variety of etiologies of retinal vasculitis were evaluated...
October 18, 2016: Retina
Jose F Condado, Vasilis Babaliaros, Travis S Henry, Brian Kaebnick, Dennis Kim, Gerald W Staton
BACKGROUND: The best treatment of patients with external pulmonary vascular compression due to advanced sarcoidosis is unknown. OBJECTIVES: To report a single-center experience of percutaneous treatment for pulmonary vascular stenosis caused by external compression due to advanced sarcoidosis. METHODS: We report a case series of 5 patients with biopsy confirmed advanced sarcoidosis, seen at our academic institution with worsening dyspnea despite increase of immunosuppressive therapy...
October 7, 2016: Sarcoidosis, Vasculitis, and Diffuse Lung Diseases: Official Journal of WASOG
Woo Sung Jang, Woong-Han Kim, Sungkyu Cho
BACKGROUND: Left pulmonary artery (LPA) stenosis with acute angulation is a common cause of reoperation after tetralogy of Fallot repair. We therefore investigated surgical outcomes of acute-angle correction angioplasty. METHODS: Between 2005 and 2012, 53 patients underwent operation for LPA stenosis as a concurrent procedure. We divided the patients into two groups according to the LPA ostium angulation: group I (acute angle, acute-angle correction angioplasty, n = 29) and group II (obtuse angle, conventional patch angioplasty, n = 24), encompassing subgroup type I (focal stenosis) and type II (diffuse stenosis)...
October 15, 2016: Annals of Thoracic Surgery
Nikolaus Luft, Piotr A Wozniak, Gerold C Aschinger, Klemens Fondi, Ahmed M Bata, René M Werkmeister, Doreen Schmidl, Katarzyna J Witkowska, Matthias Bolz, Gerhard Garhöfer, Leopold Schmetterer
Purpose: This study evaluated the validity of retinal perfusion measurements using laser speckle flowgraphy (LSFG) by means of in vitro experiments and direct comparison with dual-beam Doppler optical coherence tomography (D-OCT) in a healthy Caucasian population. Methods: The flow velocity of scattering solution pumped through a glass capillary was measured at 17 different flow velocities (range, 0.5-47 mm/s) using LSFG. The flow within the glass capillary was produced by a computer-controlled infusion pump...
October 1, 2016: Investigative Ophthalmology & Visual Science
Sven Haller, Greg Zaharchuk, David L Thomas, Karl-Olof Lovblad, Frederik Barkhof, Xavier Golay
Arterial spin labeling (ASL) is a magnetic resonance (MR) imaging technique used to assess cerebral blood flow noninvasively by magnetically labeling inflowing blood. In this article, the main labeling techniques, notably pulsed and pseudocontinuous ASL, as well as emerging clinical applications will be reviewed. In dementia, the pattern of hypoperfusion on ASL images closely matches the established patterns of hypometabolism on fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) images due to the close coupling of perfusion and metabolism in the brain...
November 2016: Radiology
Kazuhiro Murayama, Kazuhiro Katada, Motoharu Hayakawa, Hiroshi Toyama
OBJECTIVE: We aimed to clarify the cause of shortened mean transit time (MTT) in acute ischemic cerebrovascular disease and examined its relationship with reperfusion. METHODS: Twenty-three patients with acute ischemic cerebrovascular disease underwent whole-brain computed tomography perfusion (CTP). The maximum MTT (MTTmax), minimum MTT (MTTmin), ratio of maximum and minimum MTT (MTTmin/max), and minimum cerebral blood volume (CBV) (CBVmin) were measured by automatic region of interest analysis...
October 7, 2016: Journal of Computer Assisted Tomography
Chunjiang Tian, Xiangfeng Xu
OBJECTIVE: This study aims to use perfusion computed tomography to compare pancreatic perfusion in mild acute pancreatitis (MAP) versus normal pancreas. METHODS: This observational study included 39 patients with MAP and 18 patients with normal pancreatic function. Perfusion computed tomography parameters, including blood flow (BF), blood volume (BV), mean transit time, and permeability surface area product, were compared. RESULTS: Both serum and urinary amylase levels were significantly higher in patients with MAP than in controls (all Ps < 0...
October 7, 2016: Journal of Computer Assisted Tomography
Sang-Geon Cho, Zeenat Jabin, Ki Seong Park, Jahae Kim, Sae-Ryung Kang, Seong Young Kwon, Geum-Cheol Jeong, Minchul Song, Jong Sang Kim, Jae Yeong Cho, Hyun Kuk Kim, Ho-Chun Song, Jung-Joon Min, Hee-Seung Bom
PURPOSE: The aim of this study was to evaluate the prognostic value of additional evaluation of left ventricular mechanical dyssynchrony (LVMD) by gated myocardial perfusion single-photon emission computed tomography (GMPS) in patients with acute myocardial infarction (MI) and multivessel disease. METHODS: One hundred and nine acute MI patients with >50 % stenosis in at least one non-culprit artery who underwent GMPS within 2 weeks were enrolled. All patients underwent successful revascularization of the culprit arteries...
October 18, 2016: European Journal of Nuclear Medicine and Molecular Imaging
Ashley M Stokes, Charles P Hart, C Chad Quarles
High-grade gliomas are often characterized by hypoxia, which is associated with both poor long-term prognosis and therapy resistance. The adverse role hypoxia plays in treatment resistance and disease progression has led to the development of hypoxia imaging methods and hypoxia-targeted treatments. Here, we determined the tumor hypoxia and vascular perfusion characteristics of 2 rat orthotopic glioma models using 18-fluoromisonidozole positron emission tomography. In addition, we determined tumor response to the hypoxia-activated prodrug evofosfamide (TH-302) in these rat glioma models...
September 2016: Tomography: a Journal for Imaging Research
Vidhya Kumar, Yves Boucher, Hao Liu, Diego Ferreira, Jacob Hooker, Ciprian Catana, Andrew J Hoover, Tobias Ritter, Rakesh K Jain, Alexander R Guimaraes
PURPOSE: Losartan, an angiotensin II receptor blocker, can reduce desmoplasia and enhance drug delivery and efficacy through improving interstitial transport and vascular perfusion in pancreatic ductal adenocarcinoma (PDAC) models in mice. The purpose of this study was to determine whether magnetic resonance imaging (MRI) of magnetic iron oxide nanoparticles (MNPs) and micro-positron emission tomography (PET) measurements could respectively detect improvements in tumor vascular parameters and drug uptake in orthotopic PDAC in mice treated with losartan...
October 2016: Translational Oncology
Huan Xu, Guohua Deng, Chunhui Jiang, Xiangmei Kong, Jian Yu, Xinghuai Sun
Purpose: To evaluate the hyperoxia response of the retinal vascular system in different parts of the fundus using optical coherence tomography (OCT) angiography. Methods: Using an OCT angiography system and a split-spectrum amplitude decorrelation angiography (SSADA) algorithm, perfused vessel density at the macular and peripapillary regions was measured before and after breathing 80% oxygen in 10 healthy Chinese subjects. The repeatability of the hyperoxia response was also tested...
August 1, 2016: Investigative Ophthalmology & Visual Science
A Venkatraman, A Khawaja, A K Bag, M Mirza, J P Szaflarski, S Pati
Lateralized Periodic Discharges (LPDs) are commonly seen on EEG in critically-ill patients. They are often associated with seizures, but some patients may have them without seizures. Therefore, they are considered to lie in the ictal-interictal continuum. When ictal, they require multiple antiepileptic drugs to treat effectively, which can expose the patient to iatrogenic complications. Therefore, optimal management is controversial. We present here two cases where perfusion-weighted Magnetic Resonance Imaging (pMRI) was useful in distinguishing ictal from interictal LPDs...
October 5, 2016: Journal of Clinical Neurophysiology: Official Publication of the American Electroencephalographic Society
Qian Zhao, Xueqi Chen, Yun Zhou
Alzheimer's disease (AD) is a progressive neurodegenerative disorder, causing changes in memory, thinking, and other dysfunction of brain functions. More and more people are suffering from the disease. Early neuroimaging techniques of AD are needed to develop. This review provides a preliminary summary of the various neuroimaging techniques that have been explored for in vivo imaging of AD. Recent advances in magnetic resonance (MR) techniques, such as functional MR imaging (fMRI) and diffusion MRI, give opportunities to display not only anatomy and atrophy of the medial temporal lobe, but also at microstructural alterations or perfusion disturbance within the AD lesions...
March 2016: Brain Informatics
Mark Doyle, Gerald M Pohost, C Noel Bairey Merz, Leslee J Shaw, George Sopko, William J Rogers, Barry L Sharaf, Carl J Pepine, Diane V Thompson, Geetha Rayarao, Lindsey Tauxe, Sheryl F Kelsey, Robert W W Biederman
BACKGROUND: We introduce an algorithmic approach to optimize diagnostic and prognostic value of gated cardiac single photon emission computed tomography (SPECT) and magnetic resonance (MR) myocardial perfusion imaging (MPI) modalities in women with suspected myocardial ischemia. The novel approach: bio-informatics assessment schema (BIAS) forms a mathematical model utilizing MPI data and cardiac metrics generated by one modality to predict the MPI status of another modality. The model identifies cardiac features that either enhance or mask the image-based evidence of ischemia...
October 2016: Cardiovascular Diagnosis and Therapy
Kerstin Mueller, Rebecca Fahrig, Michael Manhart, Yu Deuerling-Zheng, Jarrett Rosenberg, Teri Moore, Arundhuti Ganguly, Nishita Kothary
RATIONALE AND OBJECTIVES: Intra-procedural measurement of hepatic perfusion following liver embolization continues to be a challenge. Blood volume imaging before and after interventional procedures would allow identifying the treatment end point or even allow predicting treatment outcome. Recent liver oncology studies showed the feasibility of parenchymal blood volume (PBV) imaging using an angiographic C-arm system. This study was done to evaluate the reproducibility of PBV measurements using cone beam computed tomography (CBCT) before and after embolization of the liver in a swine model...
October 10, 2016: Academic Radiology
Rafel Ramos, Xavier Albert, Joan Sala, Maria Garcia-Gil, Roberto Elosua, Jaume Marrugat, Anna Ponjoan, María Grau, Manel Morales, Antoni Rubió, Pedro Ortuño, Lia Alves-Cabratosa, Ruth Martí-Lluch
BACKGROUND: Diagnosis of unrecognized myocardial infarction (UMI) remains an open question in epidemiological and clinical studies, inhibiting effective secondary prevention of myocardial infarction. We aimed to determine the prevalence and incidence of Q-wave UMI in asymptomatic individuals aged 35 to 74years, and to ascertain the positive predictive value (PPV) of asymptomatic Q-wave to diagnose UMI. METHODS: Two population-based cross-sectional studies were conducted, in 2000 (with 10-year follow-up) and in 2005...
October 5, 2016: International Journal of Cardiology
Adam Ali Ghotbi, Andreas Kjaer, Lars Nepper-Christensen, Kiril Aleksov Ahtarovski, Jacob Thomsen Lønborg, Niels Vejlstrup, Kasper Kyhl, Thomas Emil Christensen, Thomas Engstrøm, Henning Kelbæk, Lene Holmvang, Lia E Bang, Rasmus Sejersten Ripa, Philip Hasbak
BACKGROUND: Determining infarct size and myocardial salvage in patients with ST-segment elevation myocardial infarction (STEMI) is important when assessing the efficacy of new reperfusion strategies. We investigated whether rest (82)Rb-PET myocardial perfusion imaging can estimate area at risk, final infarct size, and myocardial salvage index when compared to cardiac SPECT and magnetic resonance (CMR). METHODS: Twelve STEMI patients were injected with (99m)Tc-Sestamibi intravenously immediate prior to reperfusion...
October 14, 2016: Journal of Nuclear Cardiology: Official Publication of the American Society of Nuclear Cardiology
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