BACKGROUND AND PURPOSE: The pathophysiology of crossed cerebellar diaschisis remains to be elucidated. The mechanism responsible appears to be deafferentation through the corticopontocerebellar tract, which terminates in the cerebellar gray matter. However, few studies have demonstrated the hemodynamic and metabolic changes in the cerebellar gray matter and pons in crossed cerebellar diaschisis. METHODS: Using positron emission tomography in 24 patients with unilateral supratentorial stroke, we evaluated regional blood flow, metabolic rate of oxygen, oxygen extraction fraction, and blood volume in the cerebellar cortex and pons. Sixteen patients with significant cerebellar blood flow asymmetry, defined as a percentage difference in blood flow beyond the upper 95% confidence limit defined in eight normal subjects, were selected as the group with crossed cerebellar hypoperfusion. RESULTS: In patients with crossed cerebellar hypoperfusion, the metabolic rate of oxygen was significantly decreased in the cerebellar cortex contralateral to the supratentorial stroke, compared with that in the ipsilateral cerebellar cortex; this decrease was less than the decrease in cerebellar blood flow. The degrees of cerebellar asymmetry in these two parameters were negatively correlated with the metabolic rate of oxygen in the pons. The oxygen extraction fraction was slightly, but significantly, increased. In contrast to the ischemic state, however, the cerebellar blood volume was decreased, with no difference in the ratio of cerebellar blood flow to blood volume. CONCLUSIONS: These findings support interruption of the corticopontocerebellar tract as the mechanism of crossed cerebellar hypoperfusion. Our results also suggest a mild elevation in the oxygen extraction fraction in this state, with a mechanism distinct from ischemia.
BACKGROUND AND PURPOSE: The pathophysiology of crossed cerebellar diaschisis remains to be elucidated. The mechanism responsible appears to be deafferentation through the corticopontocerebellar tract, which terminates in the cerebellar gray matter. However, few studies have demonstrated the hemodynamic and metabolic changes in the cerebellar gray matter and pons in crossed cerebellar diaschisis. METHODS: Using positron emission tomography in 24 patients with unilateral supratentorial stroke, we evaluated regional blood flow, metabolic rate of oxygen, oxygen extraction fraction, and blood volume in the cerebellar cortex and pons. Sixteen patients with significant cerebellar blood flow asymmetry, defined as a percentage difference in blood flow beyond the upper 95% confidence limit defined in eight normal subjects, were selected as the group with crossed cerebellar hypoperfusion. RESULTS: In patients with crossed cerebellar hypoperfusion, the metabolic rate of oxygen was significantly decreased in the cerebellar cortex contralateral to the supratentorial stroke, compared with that in the ipsilateral cerebellar cortex; this decrease was less than the decrease in cerebellar blood flow. The degrees of cerebellar asymmetry in these two parameters were negatively correlated with the metabolic rate of oxygen in the pons. The oxygen extraction fraction was slightly, but significantly, increased. In contrast to the ischemic state, however, the cerebellar blood volume was decreased, with no difference in the ratio of cerebellar blood flow to blood volume. CONCLUSIONS: These findings support interruption of the corticopontocerebellar tract as the mechanism of crossed cerebellar hypoperfusion. Our results also suggest a mild elevation in the oxygen extraction fraction in this state, with a mechanism distinct from ischemia.
Authors: Wolfgang G Kunz; Wieland H Sommer; Christopher Höhne; Matthias P Fabritius; Felix Schuler; Franziska Dorn; Ahmed E Othman; Felix G Meinel; Louisa von Baumgarten; Maximilian F Reiser; Birgit Ertl-Wagner; Kolja M Thierfelder Journal: J Cereb Blood Flow Metab Date: 2017-01-13 Impact factor: 6.200
Authors: Vince I Madai; Andreas Altaner; Katharina L Stengl; Olivier Zaro-Weber; Wolf Dieter Heiss; Federico C von Samson-Himmelstjerna; Jan Sobesky Journal: J Cereb Blood Flow Metab Date: 2011-03-09 Impact factor: 6.200
Authors: Megan K Strother; Cari Buckingham; Carlos C Faraco; Daniel F Arteaga; Pengcheng Lu; Yaomin Xu; Manus J Donahue Journal: Eur J Radiol Date: 2015-11-10 Impact factor: 3.528
Authors: Thomas T Jiang; Tom O Videen; Robert L Grubb; William J Powers; Colin P Derdeyn Journal: J Cereb Blood Flow Metab Date: 2010-04-07 Impact factor: 6.200