Anterior horn cell degeneration and Bunina-type inclusions associated with dementia

The ultrastructural features of Bunina type inclusions in the anterior horn cells of a patient dying of amyotrophic lateral sclerosis with dementia appear unique. The Bunina-type inclusions are electron dense aggregates containing, and surrounded by organelle-like membranes. These inclusions appear to be a special type of autophagic vacuole, possibly arising from altered mitochondria.