The Role of Diaschisis in Stroke Recovery

Abstract

Background and Purpose-Recovery from hemiparesis after stroke has been shown to involve reorganization in motor and premotor cortical areas. However, whether poststroke recovery also depends on changes in remote brain structures, ie, diaschisis, is as yet unresolved. To address this question, we studied regional cerebral blood flow in 7 patients (meanϮSD age, 54Ϯ8 years) after their first hemiparetic stroke. Methods-We analyzed imaging data voxel by voxel using a principal component analysis by which coherent changes in functional networks could be disclosed. Performance was assessed by a motor score and by the finger movement rate during the regional cerebral blood flow measurements. Results-The patients had recovered (PϽ0.001) from severe hemiparesis after on average 6 months and were able to perform sequential finger movements with the recovered hand. Regional cerebral blood flow at rest differentiated patients and controls (PϽ0.05) by a network that was affected by the stroke lesion. During blindfolded performance of sequential finger movements, patients were differentiated from controls (PϽ0.05) by a recovery-related network and a movement-control network. These networks were spatially incongruent, involving motor, sensory, and visual cortex of both cerebral hemispheres, the basal ganglia, thalamus, and cerebellum. The lesion-affected and recovery-related networks overlapped in the contralesional thalamus and extrastriate occipital cortex. Conclusions-Motor recovery after hemiparetic brain infarction is subserved by brain structures in locations remote from the stroke lesion. The topographic overlap of the lesion-affected and recovery-related networks suggests that diaschisis may play a critical role in stroke recovery. (Stroke. 1999;30:1844-1850.)Key Words: brain mapping Ⅲ hemiparesis Ⅲ infarction Ⅲ neuronal plasticity Ⅲ tomography, emission computed I n 1914, von Monakow 1 established the concept of diaschisis as a principle for recovery from brain lesions. Accordingly, functional changes in brain structures remote from the site of a focal brain damage, ie, diaschisis, were conceptualized as processes underlying functional recovery. The role of diaschisis, however, has remained elusive. Modern neuroimaging studies have provided first clues to the existence of diaschisis by revealing that focal brain lesions are accompanied by widespread metabolic changes involving the affected cerebral hemisphere but extending into brain areas supplied by contralateral and cerebellar arteries. 2 More recently, such remote metabolic changes have been shown to be lesionspecific in terms of cerebral topography and the related clinical deficits. 3,4 Corresponding findings in experimental models of ischemia further support the concept that these remote abnormalities are brought about acutely by neurotransmitter changes and chronically by degeneration of fiber tracts. 5 However, evidence that diaschisis is also related to recovery of function is virtually lacking.In this study we tested the hypothesis that lesion-induced, remot...

Correlation of Asymmetry Indices Measured by Arterial Spin-Labeling MR Imaging and SPECT in Patients with Crossed Cerebellar Diaschisis

“…Several previous studies have suggested that CCD is not only an important prognostic factor for stroke recovery but is also associated with cognitive function and the development of vascular dementia. 10,13,[33][34][35] Therefore, the quantification of CCD can be used as a clinical prognostic indicator. However, few studies have reported a correlation between the clinical outcome and treatment response in patients and the quantitative value of CCD.…”

Responses of Neurons in the Middle Temporal Visual Area After Long-Standing Lesions of the Primary Visual Cortex in Adult New World Monkeys

“…Because Rosa et al (2000) studied MT neurons weeks after V1 lesions, they suggested that total deactivation obtained immediately after the lesions by Kaas and Krubitzer (1992) could be attributable to a widespread depression that might follow a lesion (Seitz et al, 1999). This explanation seems unlikely, given that there were normal responses in portions of MT outside the deprived zone in the study of Kaas and Krubitzer (1992).…”

Noninvasive brain stimulation in stroke rehabilitation

“…39 Imaging studies in stroke patients have shown diaschisis in cerebellar structures in the motor domain 40 -44 and also in other regions related to language 45 and vision 46 processing. Resolution of cerebellar diaschisis has been proposed as one of the mechanisms contributing to recovery of motor function after stroke; 47,48 for example, after intake of amphetamines.…”