Limits...
Cerebrospinal fluid and blood flow in mild cognitive impairment and Alzheimer's disease: a differential diagnosis from idiopathic normal pressure hydrocephalus.

El Sankari S, Gondry-Jouet C, Fichten A, Godefroy O, Serot JM, Deramond H, Meyer ME, Balédent O - Fluids Barriers CNS (2011)

Bottom Line: The patients' results were compared with those obtained for HEVs (n = 12), and for NPH patients (n = 13), using multivariate analysis.Arterial tCBF and the calculated pulsatility index were significantly greater in a-MCI patients than in HEVs.Our preliminary data show that a-MCI patients present with high systolic arterial peak flows, which are associated with higher mean total cerebral arterial flows.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Image Processing, Jules Verne University of Picardy and Amiens University Hospital, CHU d'Amiens, F-80054 Amiens cedex, France. olivier.baledent@chu-amiens.fr.

ABSTRACT

Background: Phase-contrast magnetic resonance imaging (PC-MRI) enables quantification of cerebrospinal fluid (CSF) flow and total cerebral blood (tCBF) flow and may be of value for the etiological diagnosis of neurodegenerative diseases. This investigation aimed to study CSF flow and intracerebral vascular flow in patients with Alzheimer's disease (AD) and patients with amnesic mild cognitive impairment (a-MCI) and to compare the results with patients with idiopathic normal pressure hydrocephalus (NPH) and with healthy elderly volunteers (HEV).

Methods: Ten a-MCI and 9 mild AD patients were identified in a comprehensive neurological and neuropsychological assessment. They underwent brain MRI; PC-MRI pulse sequence was performed with the following parameters: two views per segment; flip angle: 25° for vascular flow and 20° for CSF flow; field-of-view (FOV): 14 × 14 mm²; matrix: 256 × 128; slice thickness: 5 mm; with one excitation for exams on the 3 T machine, and 2 excitations for the 1.5 T machine exams. Velocity (encoding) sensitization was set to 80 cm/s for the vessels at the cervical level, 10 or 20 cm/s for the aqueduct and 5 cm/s for the cervical subarachnoid space (SAS). Dynamic flow images were analyzed with in-house processing software. The patients' results were compared with those obtained for HEVs (n = 12), and for NPH patients (n = 13), using multivariate analysis.

Results: Arterial tCBF and the calculated pulsatility index were significantly greater in a-MCI patients than in HEVs. In contrast, vascular parameters were lower in NPH patients. Cervical CSF flow analysis yielded similar values for all four populations. Aqueductal CSF stroke volumes (in μl per cardiac cycle) were similar in HEVs (34 ± 17) and AD patients (39 ± 18). In contrast, the aqueductal CSF was hyperdynamic in a-MCI patients (73 ± 33) and even more so in NPH patients (167 ± 89).

Conclusion: Our preliminary data show that a-MCI patients present with high systolic arterial peak flows, which are associated with higher mean total cerebral arterial flows. Aqueductal CSF oscillations are within normal range in AD and higher than normal in NPH. This study provides an original dynamic vision of cerebral neurodegenerative diseases, consistent with the vascular theory for AD, and supporting primary flow disturbances different from those observed in NPH.

No MeSH data available.


Related in: MedlinePlus

The dynamic interaction between the intracranial compartments. At the start of systole, an arterial volume suddenly flows into the cranium. This causes an immediate increase in the intracranial pressure (ICP). According to the Monro-Kellie doctrine, this increase in ICP is countered by a succession of flush flows through the venous and CSF compartments. The temporal coordination of these flush flows is now well documented and is organized according to the venous and CSF viscosities and flow resistances and brain compliance. The arterial peak flow (1) is first transmitted to the cervical CSF flow (2), the venous blood flow (3) and, lastly, the ventricular CSF flow (4).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3045982&req=5

Figure 4: The dynamic interaction between the intracranial compartments. At the start of systole, an arterial volume suddenly flows into the cranium. This causes an immediate increase in the intracranial pressure (ICP). According to the Monro-Kellie doctrine, this increase in ICP is countered by a succession of flush flows through the venous and CSF compartments. The temporal coordination of these flush flows is now well documented and is organized according to the venous and CSF viscosities and flow resistances and brain compliance. The arterial peak flow (1) is first transmitted to the cervical CSF flow (2), the venous blood flow (3) and, lastly, the ventricular CSF flow (4).

Mentions: Several authors [27,33-35] have suggested that cerebral atrophy or hydrocephalus can be induced by an imbalance in the interaction between three intracranial compartments: the brain parenchyma, the ventricular and subarachnoid CSF and the vascular tree (which extends from the arteries to the venous system and includes the capillary vasculature) (Figure 4). These three compartments are supposedly incompressible in steady physiological states and the adult cranium is usually considered as a rigid, closed box. As such, these systems are governed by the Monro-Kellie doctrine, which states that any volume increase in one compartment should be compensated by the withdrawal of an equal volume in one of the other two compartments, in order to maintain a steady intracranial pressure (ICP) [34,36,37]. Hence, each of these compartments can be characterized by its compliance - an indicator of distensibility, which corresponds to the pressure increase that occurs in the system when a volume is added to it.


Cerebrospinal fluid and blood flow in mild cognitive impairment and Alzheimer's disease: a differential diagnosis from idiopathic normal pressure hydrocephalus.

El Sankari S, Gondry-Jouet C, Fichten A, Godefroy O, Serot JM, Deramond H, Meyer ME, Balédent O - Fluids Barriers CNS (2011)

The dynamic interaction between the intracranial compartments. At the start of systole, an arterial volume suddenly flows into the cranium. This causes an immediate increase in the intracranial pressure (ICP). According to the Monro-Kellie doctrine, this increase in ICP is countered by a succession of flush flows through the venous and CSF compartments. The temporal coordination of these flush flows is now well documented and is organized according to the venous and CSF viscosities and flow resistances and brain compliance. The arterial peak flow (1) is first transmitted to the cervical CSF flow (2), the venous blood flow (3) and, lastly, the ventricular CSF flow (4).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3045982&req=5

Figure 4: The dynamic interaction between the intracranial compartments. At the start of systole, an arterial volume suddenly flows into the cranium. This causes an immediate increase in the intracranial pressure (ICP). According to the Monro-Kellie doctrine, this increase in ICP is countered by a succession of flush flows through the venous and CSF compartments. The temporal coordination of these flush flows is now well documented and is organized according to the venous and CSF viscosities and flow resistances and brain compliance. The arterial peak flow (1) is first transmitted to the cervical CSF flow (2), the venous blood flow (3) and, lastly, the ventricular CSF flow (4).
Mentions: Several authors [27,33-35] have suggested that cerebral atrophy or hydrocephalus can be induced by an imbalance in the interaction between three intracranial compartments: the brain parenchyma, the ventricular and subarachnoid CSF and the vascular tree (which extends from the arteries to the venous system and includes the capillary vasculature) (Figure 4). These three compartments are supposedly incompressible in steady physiological states and the adult cranium is usually considered as a rigid, closed box. As such, these systems are governed by the Monro-Kellie doctrine, which states that any volume increase in one compartment should be compensated by the withdrawal of an equal volume in one of the other two compartments, in order to maintain a steady intracranial pressure (ICP) [34,36,37]. Hence, each of these compartments can be characterized by its compliance - an indicator of distensibility, which corresponds to the pressure increase that occurs in the system when a volume is added to it.

Bottom Line: The patients' results were compared with those obtained for HEVs (n = 12), and for NPH patients (n = 13), using multivariate analysis.Arterial tCBF and the calculated pulsatility index were significantly greater in a-MCI patients than in HEVs.Our preliminary data show that a-MCI patients present with high systolic arterial peak flows, which are associated with higher mean total cerebral arterial flows.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Image Processing, Jules Verne University of Picardy and Amiens University Hospital, CHU d'Amiens, F-80054 Amiens cedex, France. olivier.baledent@chu-amiens.fr.

ABSTRACT

Background: Phase-contrast magnetic resonance imaging (PC-MRI) enables quantification of cerebrospinal fluid (CSF) flow and total cerebral blood (tCBF) flow and may be of value for the etiological diagnosis of neurodegenerative diseases. This investigation aimed to study CSF flow and intracerebral vascular flow in patients with Alzheimer's disease (AD) and patients with amnesic mild cognitive impairment (a-MCI) and to compare the results with patients with idiopathic normal pressure hydrocephalus (NPH) and with healthy elderly volunteers (HEV).

Methods: Ten a-MCI and 9 mild AD patients were identified in a comprehensive neurological and neuropsychological assessment. They underwent brain MRI; PC-MRI pulse sequence was performed with the following parameters: two views per segment; flip angle: 25° for vascular flow and 20° for CSF flow; field-of-view (FOV): 14 × 14 mm²; matrix: 256 × 128; slice thickness: 5 mm; with one excitation for exams on the 3 T machine, and 2 excitations for the 1.5 T machine exams. Velocity (encoding) sensitization was set to 80 cm/s for the vessels at the cervical level, 10 or 20 cm/s for the aqueduct and 5 cm/s for the cervical subarachnoid space (SAS). Dynamic flow images were analyzed with in-house processing software. The patients' results were compared with those obtained for HEVs (n = 12), and for NPH patients (n = 13), using multivariate analysis.

Results: Arterial tCBF and the calculated pulsatility index were significantly greater in a-MCI patients than in HEVs. In contrast, vascular parameters were lower in NPH patients. Cervical CSF flow analysis yielded similar values for all four populations. Aqueductal CSF stroke volumes (in μl per cardiac cycle) were similar in HEVs (34 ± 17) and AD patients (39 ± 18). In contrast, the aqueductal CSF was hyperdynamic in a-MCI patients (73 ± 33) and even more so in NPH patients (167 ± 89).

Conclusion: Our preliminary data show that a-MCI patients present with high systolic arterial peak flows, which are associated with higher mean total cerebral arterial flows. Aqueductal CSF oscillations are within normal range in AD and higher than normal in NPH. This study provides an original dynamic vision of cerebral neurodegenerative diseases, consistent with the vascular theory for AD, and supporting primary flow disturbances different from those observed in NPH.

No MeSH data available.


Related in: MedlinePlus