scholarly journals Cerebral Blood Flow and Metabolism of Hyperperfusion after Cerebral Revascularization in Patients with Moyamoya Disease

2012 ◽  
Vol 32 (11) ◽  
pp. 2066-2075 ◽  
Author(s):  
Yasuyuki Kaku ◽  
Koji Iihara ◽  
Norio Nakajima ◽  
Hiroharu Kataoka ◽  
Kenji Fukuda ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Moyamoya Disease ◽  
Cerebral Blood Volume ◽  
Single Photon ◽  
Photon Emission ◽  
Significant Risk ◽  
Significant Risk Factor ◽  
Oxygen Extraction Fraction ◽  
Emission Computed Tomography

In moyamoya disease (MMD), surgical revascularization may be complicated with postoperative hyperperfusion. We analyzed cerebral perfusion and metabolism using positron emission tomography (PET) or single-photon emission computed tomography (SPECT) before and after bypass surgery on 42 sides of 34 adult patients with MMD. In seven cases (16.7%) with symptomatic hyperperfusion, diagnosed by qualitative 123I-iodoamphetamine (IMP) SPECT, a subsequent PET study during postoperative subacute stages revealed significantly increased cerebral blood flow (CBF) from 34.1 ± 8.2 to 74.3 ± 12.8 mL/100 g per minute ( P < 0.01), a persistent increase in cerebral blood volume (CBV)from 5.77 ± 1.67 to 7.01 ± 1.44 mL/100 g and a significant decrease in oxygen extraction fraction (OEF) from 0.61 ± 0.09 to 0.40 ± 0.08 ( P < 0.01). Mean absolute CBF values during symptomatic hyperperfusion were more than the normal control +2 standard deviations, the predefined criteria of PET. Interestingly, two patients with markedly increased cerebral metabolic rate of oxygen (CMRO2) at hyperperfusion were complicated with postoperative seizure. Among preoperative PET parameters, increased OEF was the only significant risk factor for symptomatic hyperperfusion ( P < 0.05). This study revealed that symptomatic hyperperfusion in MMD is characterized by temporary increases in CBF >100% over preoperative values caused by prolonged recovery of increased CBV.

scholarly journals Brain Correlates of Memory Processes in Patients with Dementia of Alzheimer's Type: A Spect Activation Study

1998 ◽  
Vol 18 (4) ◽  
pp. 457-462 ◽  
Author(s):  
Dominique Cardebat ◽  
Jean-François Démonet ◽  
Michèle Puel ◽  
Alain Agniel ◽  
Gerard Viallard ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Regional Cerebral Blood Flow ◽  
Single Photon ◽  
Photon Emission ◽  
Memory Task ◽  
Frontal Region ◽  
Emission Computed Tomography ◽  
Regional Cerebral Blood ◽  
Actual Performance

Task-induced changes in regional cerebral blood flow (rCBF) during verbal episodic memory activation were compared in 17 right-handed patients with dementia of the Alzheimer's type (DAT) and 20 healthy volunteers. Regional cerebral blood flow was assessed using single photon emission computed tomography (SPECT) and an injection of 133Xe (xenon, isotope of mass 133) in 21 regions of interest (ROI) during rest, passive listening to 36 words, and memorizing of a 12-word list repeated three times. In healthy subjects, memory—listening comparison showed activation of a distributed system involving several left-sided ROI, especially the posterior inferior frontal region. In patients with DAT, the same pattern of activation was found for listening—rest comparison, and no significant changes were found in memory—listening comparison. During listening compared with rest, significant activation was observed in left-sided hypoperfused regions. A significant correlation between memory performance and rCBF recorded in patients with DAT during the memory task was found only in the right lateral frontal region, a region that was not hypoperfused significantly in patients. The involvement of this region might relate to either retrieval effort or actual performance of patients with DAT on the memory task.

scholarly journals Dose-dependent effects of the selective serotonin reuptake inhibitor citalopram: A combined SPECT and phMRI study

2019 ◽  
Vol 33 (6) ◽  
pp. 660-669 ◽  
Author(s):  
Anouk Schrantee ◽  
Michelle M Solleveld ◽  
Hilde Schwantje ◽  
Willem B Bruin ◽  
Henk-Jan MM Mutsaerts ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Serotonin Transporter ◽  
Single Photon ◽  
Photon Emission ◽  
Occipital Cortex ◽  
Emission Computed Tomography ◽  
Positron Emission ◽  
Pre Treatment ◽  
Dose Dependent

Background: Serotonin transporter blockers, like citalopram, dose-dependently bind to the serotonin transporter. Pharmacological magnetic resonance imaging (phMRI) can be used to non-invasively monitor effects of serotonergic medication. Although previous studies showed that phMRI can measure the effect of a single dose of serotoninergic medication, it is currently unclear whether it can also detect dose-dependent effects. Aims: To investigate the dose-dependent phMRI response to citalopram and compared this with serotonin transporter occupancy, measured with single photon emission computed tomography (SPECT). Methods: Forty-five healthy females were randomized to pre-treatment with placebo, a low (4 mg) or clinically standard (16 mg) oral citalopram dose. Prior to citalopram, and 3 h after, subjects underwent SPECT scanning. Subsequently, a phMRI scan with a citalopram challenge (7.5 mg intravenously) was conducted. Change in cerebral blood flow in response to the citalopram challenge was assessed in the thalamus and occipital cortex (control region). Results: Citalopram dose-dependently affected serotonin transporter occupancy, as measured with SPECT. In addition, citalopram dose-dependently affected the phMRI response to intravenous citalopram in the thalamus (but not occipital cortex), but phMRI was less sensitive in distinguishing between groups than SPECT. Serotonin transporter occupancy showed a trend-significant correlation to thalamic cerebral blood flow change. Conclusion: These results suggest that phMRI likely suffers from higher variation than SPECT, but that these techniques probably also assess different functional aspects of the serotonergic synapse; therefore phMRI could complement positron emission tomography/SPECT for measuring effects of serotonergic medication.

Improvement in Regional Cerebral Blood Flow and Cerebral Vasoreactivity after Extracranial-Intracranial Arterial Bypass

Neurosurgery ◽  
1988 ◽  
Vol 22 (5) ◽  
pp. 913-919 ◽  
Author(s):  
Hunt H. Batjer ◽  
Michael D. Devous ◽  
Phillip D. Purdy ◽  
Bruce Mickey ◽  
Frederick J. Bonte ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Regional Cerebral Blood Flow ◽  
Single Photon ◽  
Photon Emission ◽  
Emission Computed Tomography ◽  
Regional Cerebral Blood ◽  
Flow Measurements ◽  
Cerebrovascular Reserve ◽  
Neurological Improvement

Abstract Regional cerebral blood flow was measured with xenon-133 inhalation single photon emission computed tomography in a patient who developed a neurological deficit after carotid ligation. Hemispheric hypoperfusion was noted in resting studies and impaired vasoreactivity was suggested by lack of symmetrical flow augmentation after acetazolamide administration. Because of progressive neurological deterioration, an extracranial-intracranial bypass was performed. After prompt neurological improvement, repeat cerebral blood flow measurements at 1 and 9 weeks postoperatively confirmed improvement in resting flow and vasoreactivity. It is possible that decreased cerebrovascular reserve implied by measurements of vasoreactivity can identify patients who will benefit from surgical revascularization.

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