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Russell E Ware, Mariane de Montalembert, Léon Tshilolo, Miguel R Abboud
Sickle cell disease is a common and life-threatening haematological disorder that affects millions of people worldwide. Abnormal sickle-shaped erythrocytes disrupt blood flow in small vessels, and this vaso-occlusion leads to distal tissue ischaemia and inflammation, with symptoms defining the acute painful sickle-cell crisis. Repeated sickling and ongoing haemolytic anaemia, even when subclinical, lead to parenchymal injury and chronic organ damage, causing substantial morbidity and early mortality. Currently available treatments are limited to transfusions and hydroxycarbamide, although stem cell transplantation might be a potentially curative therapy...
January 31, 2017: Lancet
Felipe Rodrigues Barreto, Silvia Mangia, Carlos Ernesto Garrido Salmon
PURPOSE: To identify the impact of reduced oxygen availability on the evoked vascular response upon visual stimulation in the healthy human brain by magnetic resonance imaging (MRI). MATERIALS AND METHODS: Functional MRI techniques based on arterial spin labeling (ASL), blood oxygenation level-dependent (BOLD), and vascular space occupancy (VASO)-dependent contrasts were utilized to quantify the BOLD signal, cerebral blood flow (CBF), and volume (CBV) from nine subjects at 3T (7M/2F, 27...
November 3, 2016: Journal of Magnetic Resonance Imaging: JMRI
Jean-François Deux, Vincent Audard, Pierre Brugières, Anoosha Habibi, Elena-Maria Manea, Constance Guillaud-Danis, Bertrand Godeau, Frédéric Galactéros, Thomas Stehlé, Philippe Lang, Philippe Grimbert, Etienne Audureau, Alain Rahmouni, Pablo Bartolucci
BACKGROUND: Our understanding of the pathophysiologic processes underlying sickle cell nephropathy remains incomplete. We performed a pilot study to investigate the potential value of magnetic resonance imaging (MRI) for the assessment of kidney oxygenation and detection of potential changes to tissue perfusion and cellular integrity during a vaso-occlusive crisis. STUDY DESIGN: A case-control study. SETTING & PARTICIPANTS: 10 homozygous patients with sickle cell disease (SCD), without kidney disease (based on estimated glomerular filtration rate and albuminuria), underwent renal MRI during a vaso-occlusive crisis episode...
January 2017: American Journal of Kidney Diseases: the Official Journal of the National Kidney Foundation
C Janssens, L Claeys, P Maes, T Boiy, M Wojciechowski
We present the case of a 17-year-old boy, known with homozygous sickle cell disease, who was admitted because of generalised pain. He developed bilateral periorbital oedema and proptosis, without pain or visual disturbances. In addition to hyperhydration, oxygen and analgesia IV antibiotics were started, to cover a possible osteomyelitis. Patients with sickle cell disease are at risk for vaso-occlusive crises, when the abnormally shaped red blood cells aggregate and block the capillaries. Such a crisis typically presents at a location with high bone marrow activity, as the vertebrae and long bones...
December 2015: Acta Clinica Belgica
Veronica van der Land, Henri J M M Mutsaerts, Marc Engelen, Harriët Heijboer, Mark Roest, Martine J Hollestelle, Taco W Kuijpers, Paul J Nederkoorn, Marjon H Cnossen, Charles B L M Majoie, Aart J Nederveen, Karin Fijnvandraat
Sickle cell disease (SCD) is complicated by silent cerebral infarcts, visible as white matter hyperintensities (WMHs) on magnetic resonance imaging (MRI). Both local vaso-occlusion, elicited by endothelial dysfunction, and insufficiency of cerebral blood flow (CBF) have been proposed to be involved in the aetiology. We performed an explorative study to investigate the associations between WMHs and markers of endothelial dysfunction and CBF by quantifying WMH volume on 3.0 Tesla MRI. We included 40 children with HbSS or HbSβ(0) thalassaemia, with a mean age of 12...
January 2016: British Journal of Haematology
Carole Janssens, Lieve Claeys, Philip Maes, Tine Boiy, Marek Wojciechowski
We present the case of a 17-year-old boy, known with homozygous sickle cell disease, who was admitted because of generalised pain. He developed bilateral periorbital oedema and proptosis, without pain or visual disturbances. In addition to hyperhydration, oxygen and analgesia IV antibiotics were started, to cover a possible osteomyelitis. Patients with sickle cell disease are at risk for vaso-occlusive crises, when the abnormally shaped red blood cells aggregate and block the capillaries. Such a crisis typically presents at a location with high bone marrow activity, as the vertebrae and long bones...
July 24, 2015: Acta Clinica Belgica
Ami P Belmont, Fadi Nossair, Donald Brambilla, Marjorie Friedman, Jan Boswinkel, Andrea B Bradford, Janet L Kwiatkowski
OBJECTIVE: To assess the rates and types of complications associated with deep sedation in children with sickle cell disease (SCD) and to explore potential risk factors. STUDY DESIGN: This was a retrospective cohort study of children with SCD and a comparison group of children without SCD who underwent magnetic resonance imaging with deep sedation. The rates of general and SCD-associated sedation complications were calculated, and potential associated clinical and laboratory variables were assessed...
May 2015: Journal of Pediatrics
Ying Cheng, Peter C M van Zijl, Jun Hua
Parenchymal extravascular R2* is an important parameter for quantitative blood oxygenation level-dependent (BOLD) studies. Total and intravascular R2* values and changes in R2* values during functional stimulations have been reported in a number of studies. The purpose of this study was to measure absolute extravascular R2* values in human visual cortex and to estimate the intra- and extravascular contributions to the BOLD effect at 7 T. Vascular space occupancy (VASO) MRI was employed to separate out the extravascular tissue signal...
February 2015: NMR in Biomedicine
Laurentius Huber, Jozien Goense, Aneurin J Kennerley, Robert Trampel, Maria Guidi, Enrico Reimer, Dimo Ivanov, Nicole Neef, Claudine J Gauthier, Robert Turner, Harald E Möller
Cortical layer-dependent high (sub-millimeter) resolution functional magnetic resonance imaging (fMRI) in human or animal brain can be used to address questions regarding the functioning of cortical circuits, such as the effect of different afferent and efferent connectivities on activity in specific cortical layers. The sensitivity of gradient echo (GE) blood oxygenation level-dependent (BOLD) responses to large draining veins reduces its local specificity and can render the interpretation of the underlying laminar neural activity impossible...
February 15, 2015: NeuroImage
Mubeen F Rafay, Derek Armstrong, Peter Dirks, Daune L MacGregor, Gabrielle deVeber
BACKGROUND: Moyamoya disease is characterized by progressive cerebrovascular stenosis with recurrent cerebral ischemic events. Transient ischemic attacks are often associated with hyperventilation in children with moyamoya, suggesting hypoperfusion rather than thrombotic vaso-occlusion as a prominent mechanism. The patterns of ischemia and severity of steno-occlusive disease in such children may elucidate these mechanisms. METHODS: Children, 1 month to 18 years, with moyamoya, observed over 11 years were analyzed...
January 2015: Pediatric Neurology
Maryam Khalesi, Masoud Pezeshki Rad, Abdolkarim Hamedi, Mohammad Hassan Aelami
Moyamoya disease is a rare vaso-occlusive illness with an unknown etiology characterized by stenosis of the internal carotid arteries with spontaneous development of a collateral vascular network. A 15-month-old girl was referred to the emergency ward of Imam Reza Hospital due to decreased level of consciousness, focal seizures and fever during the previous 24 hours with an impression of encephalitis. Physical examination revealed left side hemiparesis; however brain CT-Scan did not show any significant lesions...
September 2014: Iranian Journal of Medical Sciences
Steffen N Krieger, Laurentius Huber, Benedikt A Poser, Robert Turner, Gary F Egan
PURPOSE: Yang et al. proposed an MRI technique for the simultaneous acquisition of cerebral blood volume (CBV), cerebral blood flow (CBF), and blood oxygenation level-dependent (BOLD)-weighted MRI signals (9). The purpose of this study was to develop modified version of the Yang sequence, which utilizes the advantages of 7 Tesla, leading to a robust and reliable MRI sequence. METHODS: The inversion recovery-based MR pulse sequence introduced here involves slice-saturation slab-inversion vascular space occupancy (SI-SS-VASO) MRI, double echo planar imaging readouts for arterial spin labeling, and VASO in order to correct for BOLD contamination, and a separate BOLD acquisition to minimize inversion effects on the BOLD signal...
August 2015: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Ying Cheng, Peter C M van Zijl, James J Pekar, Jun Hua
In addition to the BOLD scan, quantitative functional MRI studies require measurement of both cerebral blood volume (CBV) and flow (CBF) dynamics. The ability to detect CBV and CBF responses in a single additional scan would shorten the total scan time and reduce temporal variations. Several approaches for simultaneous CBV and CBF measurement during functional MRI experiments have been proposed in two-dimensional (2D) mode covering one to three slices in one repetition time (TR). Here, we extended the principles from previous work and present a three-dimensional (3D) whole-brain MRI approach that combines the vascular-space-occupancy (VASO) and flow-sensitive alternating inversion recovery (FAIR) arterial spin labeling (ASL) techniques, allowing the measurement of CBV and CBF dynamics, respectively, in a single scan...
December 2014: NeuroImage
Karen Buch, Memi Watanabe, Elliott J Elias, Joseph H Liao, Hernan Jara, Rohini N Nadgir, Naoko Saito, Martin H Steinberg, Osamu Sakai
OBJECTIVES: Clinical manifestations of sickle cell disease (SCD) can affect the orbit with prior reports describing changes in the lacrimal gland potentially related to chronic vaso-occlusion. The purpose of this study was to evaluate lacrimal gland volumes and quantifiable shifts in MR-relaxation times in patients with SCD. METHODS: Thirteen patients with SCD and 12 age-matched control subjects underwent magnetic resonance imaging (MRI) of the orbits with 1.5-T MRI...
September 2014: Journal of Computer Assisted Tomography
Laurentius Huber, Jozien Goense, Aneurin J Kennerley, Dimo Ivanov, Steffen N Krieger, Jöran Lepsien, Robert Trampel, Robert Turner, Harald E Möller
Decreases in stimulus-dependent blood oxygenation level dependent (BOLD) signal and their underlying neurovascular origins have recently gained considerable interest. In this study a multi-echo, BOLD-corrected vascular space occupancy (VASO) functional magnetic resonance imaging (fMRI) technique was used to investigate neurovascular responses during stimuli that elicit positive and negative BOLD responses in human brain at 7 T. Stimulus-induced BOLD, cerebral blood volume (CBV), and cerebral blood flow (CBF) changes were measured and analyzed in 'arterial' and 'venous' blood compartments in macro- and microvasculature...
August 15, 2014: NeuroImage
Emelie Lindgren, Ronnie Wirestam, Karin Markenroth Bloch, André Ahlgren, Matthias J P van Osch, Danielle van Westen, Yulia Surova, Freddy Ståhlberg, Linda Knutsson
OBJECTIVE: Dynamic susceptibility contrast MRI (DSC-MRI) tends to return elevated estimates of cerebral blood flow (CBF) and cerebral blood volume (CBV). In this study, subject-specific calibration factors (CFs), based on steady-state CBV measurements, were applied to rescale the absolute level of DSC-MRI CBF. MATERIALS AND METHODS: Twenty healthy volunteers were scanned in a test-retest approach. Independent CBV measurements for calibration were accomplished using a T1-based contrast agent steady-state method (referred to as Bookend), as well as a blood-nulling vascular space occupancy (VASO) approach...
December 2014: Magma
Xinyuan Miao, Hong Gu, Lirong Yan, Hanzhang Lu, Danny J J Wang, Xiaohong Joe Zhou, Yan Zhuo, Yihong Yang
Resting-state brain activity has been investigated extensively using BOLD contrast. However, BOLD signal represents the combined effects of multiple physiological processes and its spatial localization is less accurate than that of cerebral blood flow and volume (CBF and CBF, respectively). In this study, we demonstrate that resting-state brain activity can be reliably detected by spontaneous fluctuations of CBV-weighted signal using whole-brain gradient and spin echo (GRASE) based vascular space occupancy (VASO) imaging...
January 1, 2014: NeuroImage
F J Medina, J C Marquez, M Castillo
Cerebral fat embolism is a known but feared complication of sickle cell disease, which leads to significant morbidity. Although trauma-related fat embolism is more frequent and its diagnosis is straightforward, fat embolism secondary to bone infarcts after vaso-occlusive events can be unrecognized. Lack of criteria make the clinical diagnosis of sickle cell disease related fat embolism challenging. The neuroimaging findings are helpful to support the clinical diagnosis. Magnetic resonance imaging findings of fat embolism have been described including those seen on susceptibility-weighted imaging...
September 2012: Neuroradiology Journal
Laurentius Huber, Dimo Ivanov, Steffen N Krieger, Markus N Streicher, Toralf Mildner, Benedikt A Poser, Harald E Möller, Robert Turner
PURPOSE: MRI methods sensitive to functional changes in cerebral blood volume (CBV) may map neural activity with better spatial specificity than standard functional MRI (fMRI) methods based on blood oxygen level dependent (BOLD) effect. The purpose of this study was to develop and investigate a vascular space occupancy (VASO) method with high sensitivity to CBV changes for use in human brain at 7 Tesla (T). METHODS: To apply 7T VASO, several high-field-specific obstacles must be overcome, e...
July 2014: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
Ekaterini Solomou, Pantelis Kraniotis, Alexandra Kourakli, Theodore Petsas
The aim of this paper is to correlate the extent of silent cerebral infarcts (SCIs) on magnetic resonance imaging (MRI) with the clinical severity of sickle cell disease (SCD) in adult patients. Twenty-four consecutive adult asymptomatic SCD patients (11 male and 13 female) with a mean age of 38.4 years (range 20-59) were submitted to brain MRI on a 1 Tesla Gyroscan Intera, Philips MR scanner with a dedicated head coil. The protocol consisted of TSE T2-weighted and FLAIR images on the axial and coronal planes...
January 25, 2013: Hematology Reports
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