Introduction
- Rare tumor (<2% of neuroglial tumors), more frequent in brachycephalic breeds.
- May cause acquired hydrocephalus.
- Signs : as in space-occupying lesions in the brain. Additional signs due to transmitted pressure effects or brain herniation.
- Diagnosis : signs, MRI, definitive diagnosis only by biopsy (often post-mortem).
- Treatment : symptomatic.
- Prognosis : tend to invade the ventricular system and meninges, commonly metastasize in the cerebrospinal fluid (CSF) system.
Diagnosis
Clinical signs
Neurological deficits suggestive of space-occupying lesions in brain
- Initially vague signs, progressing to:
- Seizures.
- Behavioral changes.
- Circling - tight or wide.
- Visual impairment.
- Cranial nerve deficits.
- Altered head position.
Signs usually asymmetrical.
- Seizures, becoming more frequent and severe.
Diagnosis
Differential diagnosis
Causes of focal brain neurological signs
- Subdural hemorrhage.
- Intracranial hemorrhage
. - Abscess.
- Granulomatous meningoencephalitis
. - Other brain neoplasias
. - Acquired hydrocephalus
.
Sequelae
Prognosis
- Poor.
Expected response to treatment
- Corticosteroid therapy is likely to cause a significant and rapid improvement in clinical signs, which lasts until the tumor grows.
Reasons for treatment failure
- Tumor continues to grow.
- Metastases in the CSF system.
- Brain herniation.
Sources
Publications
Refereed papers
- Thomas W T, Wheeler S J et al(1996) MRI features of primary brain tumors in dogs. Vet Radiol Ultrasound 37 , 20-27.
- Keller E T & Madewell B R (1992) Locations and types of neoplasms in immature dogs - 69 cases (1964-1989). JAVMA 200 (10),1530-1532.
- Heidner G L, Kornegay J N, Page R L et al(1991) Radiotherapy of brain tumors in dogs. J Vet Intern Med 5 , 219-226.
- Turrel J M et al(1986) Computed tomographic characteristics of primary brain tumors in 50 dogs. JAVMA 188 (8), 850-856.
- Bailey C S & Higgins R J (1986) Characteristics of cisternal CSF associated with primary brain tumors in the dog. A retrospective study. JAMVA 188 , 414-417.
- Vandervelde M et al(1985) Immunocytochemical studies in canine neurosectodermal brain tumours. Acta Neuropathol 66 , 111-116.
Other sources of information
- Braund K G (1994) Clinical syndromes in veterinary neurology. 2nd edn. St. Louis: Mosby Year Book. pp 198-207.
- Braund K G & Rebas J L (1985) Brain ventricular tumors. ACVIM Proceedings, 3rd Annual Forum, San Diego, June 1-4. pp 157-158.



