Recent studies have suggested that cognitive impairment may be a common complication in adults with moyamoya disease (MMD). However, the mechanisms of cognitive dysfunction have not been clarified. Whether cognitive impairment may occur as a consequence of cerebral hypoperfusion and may improve after revascularization surgery has not been determined. A 39-year-old West Indian woman with subacute dysexecutive cognitive syndrome and no history of stroke was diagnosed with MMD. Magnetic resonance imaging showed an old, small cerebral infarction in the left frontal white matter and no evidence of recent cerebral ischemia. Perfusion MR imaging with acetazolamide challenge demonstrated a reduced cerebrovascular reserve in both frontal lobes. Revascularization with bur hole surgery was performed, which resulted in complete regression of initial cognitive impairment. Improvement in cognitive function correlated with the development of transdural collaterals on angiography and improvement in cerebral perfusion on MR imaging. This case suggests a relationship between cognitive dysfunction and cerebral hypoperfusion in MMD. Cognitive impairment may be potentially reversible after bur hole surgery and cerebral perfusion improvement.
Lionel Calviere, Isabelle Catalaa, Fabienne Marlats, Anne-Christine Januel, Jacques Lagarrigue and Vincent Larrue
Lionel Calviere, Isabelle Catalaa, Fabienne Marlats, Alain Viguier, Fabrice Bonneville, Christophe Cognard and Vincent Larrue
Although cognitive impairment has been reported in adults with moyamoya disease (MMD), its relationship with cerebral hemodynamic disturbances has not been investigated. The aims of the present study were to confirm the presence of dysexecutive cognitive syndrome (DCS) in adults with MMD and to explore the relationship of DCS with frontal lobe perfusion as measured by perfusion MR imaging.
Cerebral blood volume (CBV) ratio and mean transit time delay were measured in frontal and temporoparietal regions using the cerebellum as a reference region in 10 European adults with MMD. In addition, the authors calculated the cerebrovascular reserve (CVR) using the CBV ratio and the acetazolamide challenge. All patients underwent a standardized neuropsychological assessment test battery. The authors defined DCS as an impairment shown on 3 tests or more of executive function.
The authors found DCS in 6 patients. The frontal CVR was lower in patients with DCS than in patients without DCS (mean ± SD: −13.5 ± 13.2% and 20.3 ± 21.3%; p = 0.019, Mann-Whitney U-test). Other parameters of frontal perfusion and temporoparietal CVR were not correlated with DCS.
The authors' findings suggest that DCS is common in European adults with MMD and may be related to frontal perfusion impairment.