After reading our article, Dr Mark made 3 comments to which I would like to respond. First, he states that conventional MRI might have missed a small lesion and that "[i]t would have been appropriate for the authors to indicate that conventional MRI may have been insufficient. . . ." Dr Mark is entirely correct; the MRI might have missed a small hemispheric lesion. However, it is not clear that a small hemispheric lesion could induce such a profound behavioral disorder. In addition, I was always taught that no matter what imaging technique one uses, it is always possible to miss a very small lesion. Almost all well-trained neurologists know this; thus, we did not comment on the obvious.
Heilman KM. Callosal Neglect and Cognitive Impersistence—Reply. Arch Neurol. 2003;60(10):1494. doi:10.1001/archneur.60.10.1493-a