Regional Cerebral Oxygen Consumption, Blood Flow, and Blood Volume in Healthy Human Aging

Marchal, G; Rioux, Patrice; Petit-Taboué, M.C.; Sette, Giuliano; Travère, J.-M.; Poec, C. Le; Courthéoux, P.; Derlon, Jean-Michel; Baron, Jean‐Claude

doi:10.1001/archneur.1992.00530340029014

Cited by 249 publications

(153 citation statements)

References 36 publications

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“…This new instrument has been utilised to measure brain St and forearm St during ischaemia and exercise (Table I). Brain St values fit with jugular bulb saturation data, as well as with brain regional oxygen extraction values measured by positron emission tomogmphy (MARCHAL et al, 1992). Similar changes of the relative concentration of oxy-and deoxyhaemoglobin during ischaemia and exercise have been reported and discussed elsewhere (DE BLASl et al, 1993).…”

Section: Discussionsupporting

confidence: 80%

Cerebral and muscle oxygen saturation measurement by frequency-domain near-infra-red spectrometer

Blasi

Fantini

Franceschini

et al. 1995

Med. Biol. Eng. Comput.

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Section: Discussionsupporting

confidence: 80%

Cerebral and muscle oxygen saturation measurement by frequency-domain near-infra-red spectrometer

Blasi

Fantini

Franceschini

et al. 1995

Med. Biol. Eng. Comput.

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“…43 There was a tendency to lower cerebral blood flow rates in the cirrhosis groups than in the control group (Table 2) in each of the 3 regions, but this did not reach statistical significance. Studies have shown CBF to reduce with aging 44 and the current findings may be related to the somewhat higher mean age of the cirrhosis groups than that of the control group (Table 1). Regional variations similar to the current findings were found in 2 other 15 O-water PET studies of healthy controls and patients with minimal HE.…”

Section: Discussionmentioning

confidence: 50%

Brain metabolism of13N-ammonia during acute hepatic encephalopathy in cirrhosis measured by positron emission tomography

et al. 2005

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, PS BBB , was 0.21 mL blood/min/mL tissue in patients with HE, 0.31 in patients without HE, and 0.34 in healthy controls; similar differences were seen in basal ganglia and cerebellum. Metabolic trapping of blood 13 N-ammonia in the brain showed neither regional, nor patient group differences. Mean net metabolic flux of ammonia from blood into intracellular glutamine in the cortex was 13.4 mol/min/L tissue in patients with cirrhosis with HE, 7.4 in patients without HE, and 2.6 in healthy controls, significantly correlated to blood ammonia. In conclusion, increased cerebral trapping of ammonia in patients with cirrhosis with acute HE was primarily attributable to increased blood ammonia and to a minor extent to changed ammonia kinetics in the brain. (HEPATOLOGY 2006;43:42-50.) T he role of ammonia in the pathogenesis of hepatic encephalopathy (HE) and possible deleterious effects on brain energy metabolism and neurotransmission has been extensively studied. [1][2][3][4] The effects of experimental porta-caval anastomosis with or without pharmacological manipulations of ammonia metabolism have been examined in rat brain, 5-13 and the effects of excess ammonia have been tested in astrocyte cell cultures. 14 Human studies of cerebral uptake and metabolism of ammonia included postmortem examinations of brain tissue from patients dying of HE 15 and biochemical analysis of jugular vein blood samples. [16][17][18] More recently, ammonia metabolism has been tested in positron emission tomography (PET) studies of monkeys, 19 healthy humans, [19][20][21][22] and patients with cirrhosis and minimal HE. [20][21][22][23] The 13 N-ammonia PET technique can, in conjunction with proper compartmental analysis, give quantitative estimates of kinetic parameters in awake subjects.Results of early PET studies by Phelps et al. 19 indicated the presence of regional variations in cerebral 13 N-ammonia uptake in normal human subjects. Lockwood et al. 20 subsequently emphasized that the metabolism of ammonia to glutamine in brain influences cerebral ammonia uptake and later calculated a global rate of cerebral 13 Nammonia metabolism in patients with cirrhosis with minimal HE and healthy controls. 21,22 Recently, Ahl et al., 23 using dynamic PET studies, found no significant difference of the permeability-surface area product of the trans-

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“…38 We used the 15 O steady state inhalation method 39 with serial arterial 15 O counting and transmission attenuation correction. We used a high resolution, 7 slice tomograph (TTV03, LETI, Grenoble, France), 40 with final apparent image resolution ∼ 11 × 11 × 9 mm, xyz.…”

Section: Pet Imagingmentioning

confidence: 99%

“…By means of dedicated software 44 enabling MRI data acquired in three dimensions to be resliced to the PET coordinates with respect to the glabellainion line landmarks (which has known relations with the anterior commissure-posterior commissure reference points 41 ), circular regions of interest (ROIs; n=103, radius=7mm) were positioned directly over the MRI cross sections corresponding to the PET planes, according to Talairach's stereotaxic atlas, 45 to sample neocortical, limbic (especially hippocampal), subcortical (namely, caudate nucleus, lentiform nucleus, and thalamus,) and cerebellar areas. 38 These ROIs were projected on to corresponding PET matrices, and the ROI pixel values were averaged according to anatomical-functional cortical and noncortical areas to yield regional values for CBF, OEF, and CMRO 2 . 38 (Right-left percentage diVerences for homologous regions (asymmetry indices) were also calculated.…”

Section: Pet Imagingmentioning

confidence: 99%

Transient global amnesia: implicit/explicit memory dissociation and PET assessment of brain perfusion and oxygen metabolism in the acute stage

Eustache¹

2000

Neurocase

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Objectives-To assess explicit memory and two components of implicit memory-that is, perceptual-verbal skill learning and lexical-semantic priming eVects-as well as resting cerebral blood flow (CBF) and oxygen metabolism (CMRO 2 ) during the acute phase of transient global amnesia. Methods-In a 59 year old woman, whose amnestic episode fulfilled all current criteria for transient global amnesia, a neuropsychological protocol was administered, including word learning, story recall, categorical fluency, mirror reading, and word stem completion tasks. PET was performed using the 15 O steady state inhalation method, while the patient still exhibited severe anterograde amnesia and was interleaved with the cognitive tests. Results-There was a clear cut dissociation between impaired long term episodic memory and preserved implicit memory for its two components. Categorical fluency was significantly altered, suggesting word retrieval strategy-rather than semantic memory-impairment. The PET study disclosed a reduced CMRO 2 with relatively or fully preserved CBF in the left prefrontotemporal cortex and lentiform nucleus, and the reverse pattern over the left occipital cortex. Conclusions-The PET alterations with patchy CBF-CMRO 2 uncoupling would be compatible with a migraine-like phenomenon and indicate that the isolated assessment of perfusion in transient global amnesia may be misleading. The pattern of metabolic depression, with sparing of the hippocampal area, is one among the distinct patterns of brain dysfunction that underlie the (apparently) uniform clinical presentation of transient global amnesia. The finding of a left prefrontal hypometabolism in the face of impaired episodic memory and altered verbal fluency would fit present day concepts from PET activation studies about the role of this area in episodic and semantic memory encoding/ retrieval. Likewise, the changes aVecting the lenticular nucleus but sparing the caudate would be consistent with the normal performance in perceptual-verbal skill learning. Finally, unaltered lexicalsemantic priming eVects, despite left temporal cortex hypometabolism, suggest that these processes are subserved by a more distributed neocortical network.

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Regional Cerebral Oxygen Consumption, Blood Flow, and Blood Volume in Healthy Human Aging

Cited by 249 publications

References 36 publications

Cerebral and muscle oxygen saturation measurement by frequency-domain near-infra-red spectrometer

Cerebral and muscle oxygen saturation measurement by frequency-domain near-infra-red spectrometer

Brain metabolism of13N-ammonia during acute hepatic encephalopathy in cirrhosis measured by positron emission tomography

Transient global amnesia: implicit/explicit memory dissociation and PET assessment of brain perfusion and oxygen metabolism in the acute stage

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