title: Posterior fossa syndrome with a large inflammatory ponto-mesencephalic lesion.
abstract: Demonstration of a posterior fossa syndrome (PFS) in a 32-year-old male patient with clinically isolated syndrome which subsequently developed into relapsing-remitting Multiple Sclerosis. The patient suffered from double vision, coordination problems including unsteady gait and atactic dysarthria, concentration difficulties, as well as adynamia and impaired decision making. The patient clinically presented a cerebellar and dysexecutive syndrome. Cerebral magnetic resonance imaging (MRI) revealed a contrast enhancing ponto-mesencephalic lesion with a volume of 4.8cm3. Neuropsychological tests showed pronounced executive dysfunctions, reduced visuoconstructive skills, attentional deficits, echolalia, and non-fluent speech production. After cortisone and plasmapheresis, the cerebellar syndrome improved but manual fine motor skills and executive dysfunctions persisted. After three months, symptoms remitted except for a slight gait imbalance. After six months, neuropsychological tests were normal except for a moderate attention deficit. MRI revealed a clear regression of the ponto-mesencephalic lesion to a volume of 2.4cm3without contrast enhancement. This case report intends to provide an overview of the symptomatology and etiology of PFS and offers new insights into its pathomechanism demonstrating a pontine disconnection syndrome caused by a large demyelinating plaque.
authors.affiliation: Department of Neurology, Bern University Hospital and University of Bern, Switzerland. Electronic address: sigridbreit@googlemail.com.
authors.forename: S
authors.initials: S
authors.lastname: Breit
authors.affiliation: St. Anna Hospital, Neurological Praxis, St. Anna-Strasse 32, 6006 Luzern, Switzerland.
authors.forename: B
authors.initials: B
authors.lastname: Keserü
authors.affiliation: Department of Neurorehabilitation, Luzerner Kantonsspital, Spitalstrasse 16, 6000 Luzern, Switzerland.
authors.forename: T
authors.initials: T
authors.lastname: Nyffeler
authors.affiliation: Department of Neurology, Bern University Hospital and University of Bern, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Sturzenegger
authors.affiliation: Department of Neurology, Bern University Hospital and University of Bern, Switzerland. Electronic address: heinz.krestel@insel.ch.
authors.forename: H
authors.initials: H
authors.lastname: Krestel
mesh_terms: D000328:Adult; D002526:Cerebellar Diseases / Q000175:diagnosis*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008636:Mesencephalon / Q000473:pathology*; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000175:diagnosis*; D011149:Pons / Q000473:pathology
keywords: Cerebellar cognitive affective syndrome; Clinically isolated syndrome; Contrast enhancing ponto-mesencephalic lesion; Disconnection syndrome; Posterior fossa syndrome