title: Spinal subarachnoid cysts in 13 dogs.
abstract: Thirteen dogs, including 6 Rottweiler dogs, exhibiting clinical signs of spinal cord dysfunction and myelographically confirmed subarachnoid space enlargement were investigated. To characterize the lesions and to get a better understanding of their pathogenesis, different imaging techniques were used in association with explorative surgical procedures (12 dogs) and histopathologic techniques (5 dogs). All subjects underwent preoperative myelography, five of which were examined by computed tomography (CT) scanning and one by magnetic resonance imaging (MRI) as well as cerebrospinal fluid (CSF) flow measurement (velocimetry). Most animals were <12 months old (7/13 dogs) and Rottweilers were over-represented (6/13 dogs). The lesions were mainly located dorsally with respect to the spinal cord (10/13 dogs) and in the cranial cervical area (8/13 dogs). MRI suggested spinal cord deviation with signs of ventral leptomeningeal adhesion opposite the enlarged space. In one dog, velocimetry confirmed that the "cyst" was freely communicating with the surrounding CSF space. Surgical investigation confirmed leptomeninges-induced ventral adhesion in 4/5 dogs. Follow-up studies, carried out from 6 months to 2.5 years postoperatively, showed there was full recovery in 8/13 dogs. This study suggests that the compression of the spinal cord is possibly not caused by a cyst. Adhesion resulting from a combination of microtrauma and chronic inflammatory processes induces a secondary enlargement of the subarachnoid space and may be a significant causative factor in spinal cord compression and dysfunction. The over-representation of Rottweilers and the young age of the animals in the study suggest a possible genetic predisposition and an inherited etiology.
authors.affiliation: Unité Médico-chirurgicale de Neurologie, Ecole Nationale Vétérinaire de Lyon, F-69 Marcy-l'Etoile.
authors.forename: Kirsten
authors.initials: K
authors.lastname: Gnirs
authors.forename: Yannick
authors.initials: Y
authors.lastname: Ruel
authors.forename: Stephane
authors.initials: S
authors.lastname: Blot
authors.forename: Dominique
authors.initials: D
authors.lastname: Begon
authors.forename: Delphine
authors.initials: D
authors.lastname: Rault
authors.forename: Françoise
authors.initials: F
authors.lastname: Delisle
authors.forename: Lilia
authors.initials: L
authors.lastname: Boulouha
authors.forename: Marie-Anne
authors.initials: MA
authors.lastname: Colle
authors.forename: Claude
authors.initials: C
authors.lastname: Carozzo
authors.forename: Pierre
authors.initials: P
authors.lastname: Moissonnier
mesh_terms: D000818:Animals; D016080:Arachnoid Cysts / Q000000981:diagnostic imaging / Q000601:surgery / Q000662:veterinary*; D004283:Dog Diseases / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery; D004285:Dogs; D009192:Myelography / Q000662:veterinary; D014057:Tomography, X-Ray Computed