BLOOD FLOW ABNORMALITIES IN SICKLE CELL ANEMIA

2005 ◽  
Author(s):  
ANTHONY TZE-WAI CHEUNG
Keyword(s):  
Blood Flow ◽  
Sickle Cell ◽  
Sickle Cell Anemia

scholarly journals Is there a role for selective vasodilation in the management of sickle cell disease?

Blood ◽  
1988 ◽  
Vol 71 (3) ◽  
pp. 597-602 ◽  
Author(s):  
GP Rodgers ◽  
MS Roy ◽  
CT Noguchi ◽  
AN Schechter
Keyword(s):  
Blood Flow ◽  
Steady State ◽  
Sickle Cell Disease ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Microvascular Obstruction ◽  
Controlled Study ◽  
Control Group ◽  
Cell Disease ◽  
Retinal Arteriolar

Abstract To test the hypothesis that microvascular obstruction to blood flow at the level of the arteriole may be significant in individuals with sickle cell anemia, the ophthalmologic effects of orally administered nifedipine were monitored in 11 steady-state patients. Three patients with evidence of acute peripheral retinal arteriolar occlusion displayed a prompt reperfusion of the involved segment. Two other patients showed fading of retroequatorial red retinal lesions. Color vision performance was improved in six of the nine patients tested. The majority of patients also demonstrated a significant decrease in the amount of blanching of the conjunctiva which reflects improved blood flow to this frequently involved area. Such improvements were not observable in a control group of untreated stable sickle cell subjects. These findings support the hypothesis that inappropriate vasoconstriction or frank vasospasm may be a significant factor in the pathogenesis of the microvascular lesions of sickle cell disease and, further, that selective microvascular entrapment inhibition may offer an additional strategy to the management of this disorder. We believe a larger, placebo-controlled study with nifedipine and similar agents is warranted.

scholarly journals Inverse correlation between cerebral blood flow measured by continuous arterial spin-labeling (CASL) MRI and neurocognitive function in children with sickle cell anemia (SCA)

Blood ◽  
2006 ◽  
Vol 108 (1) ◽  
pp. 379-381 ◽  
Author(s):  
John J. Strouse ◽  
Christiane S. Cox ◽  
Elias R. Melhem ◽  
Hanzhang Lu ◽  
Michael A. Kraut ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Arterial Spin Labeling ◽  
Complete Blood Count ◽  
Spin Labeling ◽  
Neurocognitive Impairment ◽  
Continuous Arterial Spin Labeling ◽  
L 14

Overt stroke, clinically “silent” cerebral infarct, and neurocognitive impairment are frequent complications of sickle cell anemia (SCA). Current imaging techniques have limited sensitivity and specificity to identify children at risk for neurocognitive impairment. We prospectively evaluated 24 children with SCA with a neurologic exam, complete blood count, transcranial Doppler ultrasound (TCD), measurement of intelligence quotient (IQ), and magnetic resonance imaging (MRI) with measurement of cerebral blood flow (CBF) using continuous arterial spin-labeling (CASL) MRI. Average CBF to gray matter was 112 ± 36 mL/100 g/min. We identified a strong inverse relationship between performance IQ and CBF (-1.5 points per 10 mL/100 g/min increase in CBF, P = .013). Elevated steady-state white blood cell count (≥ 14 × 109/L [14 000/μL]) was associated with lower full scale IQ (86 ± 9 vs 99 ± 10, P = .005). CASL MRI may identify children with neurocognitive impairment, before damage is evident by structural MRI or TCD. (Blood. 2006;108:379-381)

scholarly journals Vasculopathy, inflammation, and blood flow in leg ulcers of patients with sickle cell anemia

2013 ◽  
Vol 89 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Caterina P. Minniti ◽  
Kara-Marie H. Delaney ◽  
Alexander M. Gorbach ◽  
Dihua Xu ◽  
Chyi-Chia Richard Lee ◽  
...  
Keyword(s):  
Blood Flow ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Leg Ulcers

scholarly journals Functional and anatomical evidence of cerebral tissue hypoxia in young sickle cell anemia mice

2016 ◽  
Vol 37 (3) ◽  
pp. 994-1005 ◽  
Author(s):  
Lindsay S Cahill ◽  
Lisa M Gazdzinski ◽  
Albert KY Tsui ◽  
Yu-Qing Zhou ◽  
Sharon Portnoy ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Brain Tissue ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Cell Model ◽  
Ex Vivo ◽  
Tissue Hypoxia ◽  
Brain Physiology ◽  
The Brain

Cerebral ischemia is a significant source of morbidity in children with sickle cell anemia; however, the mechanism of injury is poorly understood. Increased cerebral blood flow and low hemoglobin levels in children with sickle cell anemia are associated with increased stroke risk, suggesting that anemia-induced tissue hypoxia may be an important factor contributing to subsequent morbidity. To better understand the pathophysiology of brain injury, brain physiology and morphology were characterized in a transgenic mouse model, the Townes sickle cell model. Relative to age-matched controls, sickle cell anemia mice demonstrated: (1) decreased brain tissue pO2 and increased expression of hypoxia signaling protein in the perivascular regions of the cerebral cortex; (2) elevated basal cerebral blood flow , consistent with adaptation to anemia-induced tissue hypoxia; (3) significant reduction in cerebrovascular blood flow reactivity to a hypercapnic challenge; (4) increased diameter of the carotid artery; and (5) significant volume changes in white and gray matter regions in the brain, as assessed by ex vivo magnetic resonance imaging. Collectively, these findings support the hypothesis that brain tissue hypoxia contributes to adaptive physiological and anatomic changes in Townes sickle cell mice. These findings may help define the pathophysiology for stroke in children with sickle cell anemia.

Evaluation of Moyamoya Disease in Sickle Cell Anemia Patients After Encephaloduroarteriosynangiosis

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1059-1059
Author(s):  
Janice Earl ◽  
Peter Sun ◽  
Kenneth Martin ◽  
Keith C. Quirolo ◽  
Elliott Vichinsky ◽  
...  
Keyword(s):  
Blood Flow ◽  
Sickle Cell ◽  
Moyamoya Disease ◽  
Sickle Cell Anemia ◽  
Perfusion Imaging ◽  
Research Funding ◽  
Well Being ◽  
Partial Obstruction ◽  
Time To Peak ◽  
Peak Enhancement

Abstract Abstract 1059 Background: Moyamoya disease is a progressive cerebrovascular complication of sickle cell anemia characterized by collateral arterial formation in response to progressive stenosis of the large intracranial arteries. Despite chronic transfusions, moyamoya is associated with a high risk of stroke recurrence. Encephaloduroarteriosynangiosis (EDAS) is a surgical technique used to reestablish or augment cerebral perfusion in patients with moyamoya disease. However, evidence for its efficacy in SCA patients is limited. We initiated a prospective study to determine whether EDAS is safe and increases blood flow to ischemic areas of brain in SCA patients with moyamoya. Methods/Results: SCA patients who had complete or partial obstruction of the dICA with progression to moyamoya disease were eligible for EDAS. Progressive cognitive decline, dystonia and persistent seizures were also factors influencing eligibility. Seven SCA patients (age: median 16yrs, range 4–23yrs; sex: 5F/2M ) with moyamoya disease underwent encephaloduroarteriosynangiosis (EDAS) procedures between 3/2007 and 9/2010. All 7 patients were regularly transfused for a history of stroke or MRA-documented ICA stenosis. Complete or partial obstruction of the dICA with moyamoya changes was detected on MRA scans and confirmed by cerebral angiography. Bilateral (n = 2) or unilateral (n = 5) encephaloduroarteriosynangiosis procedures in which the superficial temporal artery is transplanted through a small craniotomy with dural and arachnoid opening and sutured to the pia were performed. Perfusion MR-weighted imaging was performed pre- and post-operatively to evaluate changes in relative cerebral blood volume and time to peak enhancement. Results: All patients have remained free of neurovascular complications and have had no new ischemic changes on MRI with an average follow-up of 26 months. All patients subjectively reported improvement in overall well-being. A decrease in the frequency of headaches (n=1), resolution of seizures (n=2) and improved gait (n=1) were also observed. Collateral anastomoses between external and internal carotid arteries were established by MRA in all patients. All 4 patients who had pre and post-procedure MRA perfusion imaging showed a reduction in the delay of time to peak enhancement in the affected territory after EDAS. Conclusion: Our results indicate that EDAS is a safe and effective surgical procedure to re-establish blood flow to ischemic brain tissue in patients with SCA who develop moyamoya disease. MRA perfusion imaging may be a useful tool to evaluate improved perfusion status after EDAS. Further examination of neuropsychologic correlates, such as executive function, with EDAS procedures in these patients is presently underway. Disclosures: Vichinsky: Novartis: Research Funding; Apotex: Research Funding.

scholarly journals PF740 CEREBRAL BLOOD FLOW IN ADOLESCENTS WITH SICKLE CELL ANEMIA RECEIVING VOXELOTOR

HemaSphere ◽  
2019 ◽  
Vol 3 (S1) ◽  
pp. 324 ◽  
Author(s):  
J.H. Estepp ◽  
W. Wang ◽  
S. Hwang ◽  
C. Hillenbrand ◽  
R. Ogg
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Sickle Cell ◽  
Sickle Cell Anemia

Correlation Between Cerebral Blood Flow Velocities Measured By Magnetic Resonance and Transcranial Doppler Ultrasound in Children with Sickle Cell Anemia

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2496-2496
Author(s):  
Monica L. Hulbert ◽  
Dustin K. Ragan ◽  
Hongyu An ◽  
Cihat Eldeniz ◽  
Geetika Khanna ◽  
...  
Keyword(s):  
Blood Flow ◽  
Magnetic Resonance ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Transcranial Doppler ◽  
Arterial Stenosis ◽  
Acquisition Time ◽  
Transfusion Therapy ◽  
Blood Flow Velocities ◽  
Flow Velocities

Abstract Background Transcranial Doppler (TCD) ultrasonography is the standard stroke screening test for children with sickle cell anemia (SCA). However, approximately 10% of children have inadequate ultrasonographic windows for a successful TCD study, and some clinical sites may lack the equipment or personnel to perform TCDs in children. Magnetic resonance imaging (MRI) techniques can also measure blood flow velocities and could substitute for TCD in these clinical scenarios. We tested the hypothesis that MRI-derived middle cerebral artery (MCA) blood flow velocities would correlate with TCD-derived MCA blood flow velocities in children with SCA. Methods Children age 6 years and up with SCA at their baseline state of health underwent TCD and MRI as part of a prospective clinical study. Imaging TCD of the bilateral MCAs to determine time-average mean of maximum blood flow velocities (TCD-CBFV) were performed using clinical ultrasound equipment. MRIs were performed at 3T without sedation. MRI cerebral time-averaged mean blood flow velocities (MR-CBFV) were measured in the MCAs using phase contrast sequences without cardiac cycle gating to shorten acquisition time and reduce ghosting artifacts. TCD- and MR-CBFV of each hemisphere were compared. Silent cerebral infarctions (SCIs) were categorized as present or absent in each hemisphere. Non-parametric tests were used with a level of significance of <0.05. Statistics were performed in SPSS version 21. Results Twenty hemispheres from 15 children had both TCD-CBFV and MR-CBFV measurements. Median age was 9 years (IQR 6.25-10). In these children, two hemispheres had unobtainable TCDs due to skull thickness, and eight hemispheres had MR-CBFV excluded due to patient motion or poor positioning. The median TCD-CBFV was 116 cm/sec (IQR 90.25-124) and none of the included hemispheres had arterial stenosis or TCD-CBFV in the conditional or abnormal range. Eight included hemispheres were from children receiving chronic blood transfusion therapy for primary or secondary stroke prevention. There was a linear relationship between TCD-CBFV and MR-CBFV (Spearman correlation, ρ=0.781, p<0.001, Figure) although MR-CBFV values were lower than TCD-CBFV values (median difference 32.6%, IQR 26.7-42.8). When evaluating only the children not receiving chronic transfusion therapy, MR-CBFV was significantly higher in 8 hemispheres without SCIs (median 80 cm/sec, IQR 77.8-87.8) than in 4 hemispheres with SCIs (median 60 cm/sec, IQR 44.6-72.3, p=0.004). In a multivariate model adjusting for age, MR-CBFV continued to be associated with presence of SCIs (p=0.036). There was no significant difference in TCD-CBFV when analyzed by SCI status (p=0.2), consistent with published studies of TCD-CBFV and SCIs. Conclusions In this small cohort of children with SCA, MR-CBFV correlated significantly with TCD-CBFV, but MR-CBFV values were approximately 30% lower than TCD-CBFV. This may be due to the method of acquiring MR-CBFV via non-gated methodology, which is known to produce lower blood flow velocity estimates. Further work is needed to determine a threshold for high-risk MR-CBFV values before this modality could be used as a substitute for TCD screening. Lower MR-CBFV was associated with SCIs, suggesting a potential role for MR-CBFV in predicting SCI risk. The relationship between MR-CBFV and SCIs should be explored further. Disclosures Hulbert: Pfizer, Inc.: Other: spouse employment. Fields:NeuroPhage Pharmaceuticals: Equity Ownership, Membership on an entity's Board of Directors or advisory committees.

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