In 1914, Von Monakow described diaschisis, the recovery of lost cortic
al function in regions positionally distant from, but linked by neuron
al tracts to, the primary site of cortical damage, Cerebellar diaschis
is after cortical insult is detailed in the literature; however, corti
cal diaschisis after cerebellar insult remains a rarely reported occur
rence. We describe a 36-year-old woman with rupture of a right-sided c
erebellar arteriovenous malformation who developed such expected cereb
ellar signs as ataxia, dysmetria, and nystagmus. Days later, the patie
nt developed profound impulsivity, disinhibition, and psychomotor agit
ation. Single photon emission computed tomography (SPECT) showed decre
ased perfusion of the bilateral frontal and temporal lobes, consistent
with regional loss of neural activity. Eventual clinical improvement
corresponded with reperfusion of those regions, identified on follow-u
p SPECT. This cave documents cortical diaschisis following cerebellar
insult and shows that diaschisis must be considered in patients with c
erebral injury manifesting cortical deficits remote from the site of p
rimary pathology. (C) 1997 by the American Congress of Rehabilitation
Medicine and the American Academy of Physical Medicine and Rehabilitat
ion.