Brain stem infarction and diaschisis. A SPECT cerebral perfusion study.

Abstract

Background and Purpose: We studied six patients suffering from pure, unilateral brain stem infarction to explore the association of remote cerebral and cerebellar blood flow changes with damage at different sites of this region of the brain.Methods: We used single-photon emission computed tomography and llliodoamphetamine to measure regional differences in tracer uptake. Qualitative image analysis and calculated asymmetry indexes were correlated to the location of the infarcted area on magnetic resonance imaging and to the patients' clinical findings.Results: Significant perfusion asymmetries were noted in the two patients with infarction in the upper pons but not in those with lesions below this level. They comprised a contralateral cerebellar and ipsilateral supratentorial hypoactivity that was most marked in the frontoparietal cortex. There was no clear relation between the patterns of cerebral or cerebellar tracer uptake and specific neurological findings.Conclusions: Remote perfusion changes after pure brain stem infarction may be seen both infratentorially and supratentorially and depend on the lesion site rather than on the neurological deficit. In this context, our study confirmed damage to the corticopontocerebellar pathways as the key event in the genesis of a crossed cerebellar diaschisis. The exact mechanisms causing ipsilateral cerebral hemispheric diaschisis await further clarification. (Stroke 1993;24:1162-1166

Isolated dysarthria due to extracerebellar lacunar stroke: a central monoparesis of the tongue

“…41 In our patients HMPAO-SPECT studies showed no cerebellar diaschisis, indicating that corticopontocerebellar tract function was unimpaired, although partial corticopontocerebellar tract dysfunction cannot completely be excluded due to the limited spatial resolution of HMPAO-SPECT.…”

Preserved motor-evoked potentials but without good motor recovery in a patient with decerebrate rigidity☆

“…Brainstem lesions may produce cerebellar diaschisis, 9,10 which may last 20 years after stroke. 11 Although single photon emission computed tomography or positron emission tomography was not done in our patient, we infer that she had cerebellar dysfunction because of diaschisis.…”

Cavernous Angioma with Olivary Hypertrophy and Contralateral Cerebellar Diaschisis.

“…This explains howeither a supratentorial lesion maycause crossed cerebellar diaschisis or an infratentorial lesion maycause contralateral cerebellar diaschisis. In patients with a unilateral pontine lesion, contralateral cerebellar diaschisis and ipsilateral supratentorial hypoperfusion have been observed (3,6). The lesions of the cerebropontine-cerebellar tract within the pons are thought to produce contralateral cerebellar diaschisis.…”

“…Involvement of the cerebropontine-cerebellar tract is thought to result in crossed cerebellar diaschisis; however, infratentorial lesions interrupting the cerebropontine-cerebellar tract mayalso result in contralateral cerebellar diaschisis in some patients (2)(3)(4) [It may be more precise to refer to cerebellar diaschisis with contralateral supratentorial lesion as "crossed cerebellar diaschisis", and cerebellar diaschisis with contralateral infratentorial lesion as "contralateral cerebellar diaschisis"]. Here, we describe a patient with a tegmental lesion whoappears to have developed contralateral cerebellar diaschisis as a result of interruption of the dentato-olivary pathway.…”