Clinical Features, Imaging Characteristics, and Long-term Outcome of Dogs with Cranial Meningocele or Meningoencephalocele

J Vet Intern Med. 2017 Mar;31(2):505-512. doi: 10.1111/jvim.14638. Epub 2017 Feb 28.

Abstract

Background: The term meningoencephalocele (MEC) describes a herniation of cerebral tissue and meninges through a defect in the cranium, whereas a meningocele (MC) is a herniation of the meninges alone.

Hypothesis/objectives: To describe the clinical features, magnetic resonance imaging (MRI) characteristics, and outcomes of dogs with cranial MC and MEC.

Animals: Twenty-two client-owned dogs diagnosed with cranial MC or MEC.

Methods: Multicentric retrospective descriptive study. Clinical records of 13 institutions were reviewed. Signalment, clinical history, neurologic findings and MRI characteristics as well as treatment and outcome were recorded and evaluated.

Results: Most affected dogs were presented at a young age (median, 6.5 months; range, 1 month - 8 years). The most common presenting complaints were seizures and behavioral abnormalities. Intranasal MEC was more common than parietal MC. Magnetic resonance imaging identified meningeal enhancement of the protruded tissue in 77% of the cases. Porencephaly was seen in all cases with parietal MC. Cerebrospinal fluid (CSF) analysis identified mild abnormalities in 4 of 11 cases. Surgery was not performed in any affected dog. Seventeen patients were treated medically, and seizures were adequately controlled with anti-epileptic drugs in 10 dogs. Dogs with intranasal MEC and mild neurologic signs had a fair prognosis with medical treatment.

Conclusion and clinical importance: Although uncommon, MC and MEC should be considered as a differential diagnosis in young dogs presenting with seizures or alterations in behavior. Medical treatment is a valid option with a fair prognosis when the neurologic signs are mild.

Keywords: Cerebral malformation; Cranioschisis; Porencephaly; Seizures.

MeSH terms

  • Animals
  • Anticonvulsants / administration & dosage
  • Cerebrospinal Fluid / chemistry
  • Cerebrospinal Fluid / cytology
  • Dog Diseases / diagnostic imaging*
  • Dog Diseases / drug therapy
  • Dogs
  • Encephalocele / diagnostic imaging
  • Encephalocele / veterinary*
  • Female
  • Magnetic Resonance Imaging / veterinary
  • Male
  • Meningocele / diagnostic imaging
  • Meningocele / veterinary*
  • Porencephaly / veterinary
  • Retrospective Studies
  • Seizures / drug therapy
  • Seizures / veterinary
  • Treatment Outcome

Substances

  • Anticonvulsants