1. From the Department of Human Pathology, Policlinico Universitario G. Martino, Messina, Italy (Drs Barresi and Tuccari); the Units of Human Pathology, (Drs Cerasoli and Morigi) and Neurosurgery (Dr Cremonini), M. Bufalini Hospital, Cesena, Italy; and the Unit of Neuroradiology, Hospital of S. Marino, S. Marino Republic (Dr Volpini)