Microcystic meningioma of the fourth ventricle in a dog.
A 5-year-old female cross-breed dog was presented with a 1-month history of progressive changes in the posture of the head and in the gait. At neurological examination the dog showed a central vestibular syndrome lateralized to the left. MRI showed a space occupying lesion within the fourth ventricle, characterized by iso- to hypointensity in T1 and hyperintensity in T2 with a heterogeneous contrast uptake. Histologically, a neoplasia composed of meningothelial cells forming compact whorls with slight atypia, and stellate cells delimitating microcysts containing eosinophilic fluid was observed. Neoplastic cells were positive for vimentin and negative for GFAP and FVIII. A diagnosis of intraventricular microcystic meningioma was achieved. Intraventricular meningiomas in dogs are rarely encountered and reports of meningiomas within the fourth ventricle have not yet been described. Although choroid plexus tumor is the most frequent neoplasia localized in the fourth ventricle, intraventricular meningioma should be included in the differential diagnoses.
Salvadori
Claudia
C
Department of Animal Pathology, Faculty of Veterinary Medicine, University of Pisa, Italy.
Pintore
Maria Domenica
MD
Ricci
Emanuele
E
Konar
Martin
M
Tartarelli
Chiara Laura
CL
Gasparinetti
Nicola
N
Cantile
Carlo
C
D000818:Animals; D001932:Brain Neoplasms / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*; D004283:Dog Diseases / Q000175:diagnosis* / Q000473:pathology; D004285:Dogs; D005260:Female; D020546:Fourth Ventricle / Q000473:pathology*; D008579:Meningioma / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*