Résumé
The Pisa syndrome is a rare extrapyramidal side effect with twisting and bending characteristics of the upper trunk, neck, and head, usually caused by neuroleptic treatment. However, there have been no reports of Pisa syndrome in cholinesterase inhibitor therapy. We report 2 female patients of Alzheimer's disease with Pisa syndrome after cholinesterase inhibitor ther-apy. The postural disturbance in these patients was completely resolved after the cessation of the cholinesterase inhibitor. Although the pathophysiology of Pisa syndrome appears to be extremely complicated and poorly understood, it may be of importance to consider the relationship between acetylcholine and Pisa syndrome. Therefore, the present cases provide a novel viewpoint on the underlying mechanism of the Pisa syndrome and the role of acetylcholine in the movement disorder.