Related Experiment Videos
A decrease in regional cerebral blood volume and hematocrit in crossed cerebellar diaschisis
H Yamauchi1, H Fukuyama, Y Nagahama
1Department of Neurology, Brain Pathophysiology Faculty of Medicine, Kyoto University, Japan. ymuc@kuhp.kyoto-u.ac.jp
Insights
Crossed cerebellar diaschisis (CCD) reduces total cerebral blood volume (CBV). This condition disproportionately decreases red blood cell volume, leading to lower hematocrit in the affected cerebellar hemisphere.
Area of Science:
- Neuroscience
- Cerebrovascular Physiology
Background:
- Crossed cerebellar diaschisis (CCD) pathophysiology is not fully understood.
- Deafferentation-induced metabolic suppression may cause vasoconstriction, impacting cerebral blood volume (CBV).
- Potential differential effects on red blood cell and plasma flow require investigation.
Purpose of the Study:
- To determine if CCD decreases total CBV.
- To investigate differential effects of CCD on cerebral red blood cell volume (CRCV) and cerebral plasma volume (CPV).
- To assess if CCD alters hematocrit.
Main Methods:
- Positron emission tomography (PET) used in 7 patients with unilateral supratentorial infarct and CCD.
- 15O-labeled carbon monoxide tracer for CRCV assessment.
- 62Cu-labeled human serum albumin-dithiosemicarbazone tracer for CPV assessment.
Main Results:
- Significantly decreased CRCV, CPV, and total CBV in the cerebellar cortex contralateral to the infarct.
- CRCV reduction was greater than CPV reduction.
- Hematocrit was decreased in the contralateral cerebellar cortex.
Conclusions:
- CCD may decrease total CBV, potentially due to vasoconstriction from deafferentation-induced metabolic suppression.
- A more pronounced decrease in CRCV compared to CPV may lead to reduced hematocrit in CCD.
- Findings elucidate a potential mechanism for altered blood composition in CCD.
Background And Purpose:
The pathophysiology of crossed cerebellar diaschisis (CCD) remains to be elucidated. In CCD, the metabolic suppression resulting from deafferentation may cause vasoconstriction, which may result in a decrease in cerebral blood volume (CBV) and may differentially affect the flows of red blood cells and of plasma. The purpose of this study was to investigate whether CCD decreases the total CBV (cerebral red blood cell volume [CRCV] plus cerebral plasma volume [CPV]) and, if so, whether CCD differentially affects the CRCV and CPV, resulting in a change in hematocrit.
Methods:
We used positron emission tomography to study 7 patients with a unilateral supratentorial infarct and CCD. The distributions of CRCV and CPV were assessed by using 15O-labeled carbon monoxide and 62Cu-labeled human serum albumin-dithiosemicarbazone tracers, respectively. The CRCV, CPV, and calculated hematocrit values were compared between the cerebellar hemispheres.
Results:
In the cerebellar cortex contralateral to the supratentorial infarct, the values of CRCV, CPV, and total CBV were significantly decreased compared with those in the ipsilateral cerebellar cortex. The CRCV was decreased to a greater degree than the CPV, and the value of the hematocrit was decreased in the contralateral cerebellar cortex.
Conclusions:
CCD may decrease the total CBV, which may reflect vasoconstriction caused by decreased metabolism due to deafferentation. In addition, the more pronounced decrease in CRCV than in CPV may result in a decrease in hematocrit in CCD.