[Neuropathology associated with dementia]

As dementing diseases are too numerous to refer to all of them, I confine my description to the neuropathology of amyotrophic lateral sclerosis with dementia (ALSD), and cerebral vascular pathology of three unique vascular diseases causing dementia. 1) ALSD: The cortical neuropathology of this condition exhibit two main unique profiles in addition to mainly temporal lobe-located cortical changes. One is ubiquitin-positive intraneuronal cytoplasmic inclusions, and the other a localized neuronal degeneration in the transitional zone between the hippocampal CA1 and subiculum. 2) Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL): The characteristic vascular change of this condition is marked intimal thickening of the middle and small arteries with relatively preserved smooth muscle cells in the media. The scalp arteries escape this lesion, indicating non-ischemic pathomechanisms for the baldness seen in this condition. 3) Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL): The main lesions of the cerebral vessels are smooth muscle cell degeneration of deep perforating and small meningeal arteries with deposition of granular osomiophilic material in the media of the affected vessels. 4) Sneddon syndrome: This condition characterized by livedo reticularis and recurrent multiple infarctions shows marked sclerotic changes in the deep perforating arterioles and main cerebral arteries with relatively spared middle- and small-sized meningeal arteries.