Secondary changes in cerebellar perfusion (diaschisis) in hemiplegia during childhood: SPECT study of 55 children.

Diaschisis is a functional impairment at a site in the brain remote from the lesion causing it. An investigation of cerebellar diaschisis in childhood was undertaken to better understand the functional maturation of the corticopontocerebellar tract in developing brain. A retrospective study of cerebellar diaschisis in 55 hemiplegic children was conducted using single-photon emission computed tomography (SPECT) with 123I-IMP. Cerebellar diaschisis was evaluated by 2 authors. Crossed cerebellar diaschisis (CCD) was found in 6 of 55 patients. SPECT findings of patients who presented with CCD disclosed supratentorial hypoperfusion of varying degrees, from focally to the whole hemisphere; however, patients had frontal and/or parietal hypoperfusion in common. A second type of cerebellar diaschisis also was demonstrated. Cerebellar hypoperfusion ipsilateral to supratentorial lesions, ipsilateral cerebellar diaschisis (ICD), was observed in 10 of 55 patients. CCD occurred in the patients who suffered from brain injuries after 7 years, 5 months of age, while ICD manifested in patients whose brain injuries occurred before 3 years, 1 month of age. The production of remote effects, such as CCD and ICD, could be closely related to maturation of the corticopontocerebellar tract in the developing brain during childhood.