Does Vascular Dementia Exist? Report of Two Cases Previously Diagnosed with Vascular Dementia Treated by Means of Ventriculoatrial Shunts

Abstract

Vascular dementia (VaD) is the second most common cause of dementia after Alzheimer's disease. While new therapeutic modalities have been available for Alzheimer's disease, there is currently no effective treatment for VaD. We encountered two cases with VaD who recovered their cognitive function to normal levels after ventriculoatrial shunt (VA shunt). Both cases complained cognitive impairment shortly after cerebral infarctions. Their brain images showed ventricular dilatation without the findings of disproportionately enlarged subarachnoid space hydrocephalus, which is regarded as characteristic for idiopathic normal pressure hydrocephalus (iNPH). Both cases were initially diagnosed as VaD by board neurosurgeons. However, since they showed positive response to lumbar tap test, VA shunts were performed. Both cases recovered their cognitive function to normal level. Their excellent cognitive outcomes after VA shunts indicate that many iNPH patients with lacunar infarcts may possibly be misdiagnosed as VaD.

Keywords: DESH; VA shunt; dementia; iNPH; vascular dementia.

Fig. 1

Multiple lacunar infarct in Case 1. ( A ) Evans' index is 0.34. Freehand circles were drawn by the board neurosurgeon to show lacunar infarcts. ( B ) Neither abnormal Sylvian fissure dilatation nor high convexity tightness were observed.

Fig. 2

Multiple lacunar infarcts in Case 2. ( A ) Evans' index is 0.27 and anterior horn roundedness was seen. ( B ) No abnormal Sylvian fissure dilatation or high convexity tightness were noted. Third ventricular ballooning was observed. ( C ) Lacunar infarct in the corona radiata is clearly seen. ( D ) No abnormal Sylvian fissure dilatation or high convexity tightness were noted. Third ventricular ballooning was observed. Multiple lacunar infarcts are seen.