Rare canine encephalocele case highlights surgical option: full analysis

A new case report in Animals highlights the surgical management of a rare canine encephalocele communicating with the nasal cavity, a skull-base defect in which intracranial tissue herniates through the cribriform plate into the nasal passage. In the reported case, a young American Cocker Spaniel presented with seizures, and advanced imaging showed brain tissue extending into the nasal cavity. The surgical team resected the protruding tissue and reconstructed the skull base, after which the dog recovered without further seizures during follow-up. The article was published on May 2, 2026. (mdpi.com)

That matters because canine encephaloceles and meningoencephaloceles are rare enough that most of the veterinary literature consists of isolated case reports and small retrospective series. A 2017 study in the Journal of Veterinary Internal Medicine reviewing 22 dogs found that epileptic seizures were the most common presenting sign, seen in 77% of cases, and that 17 of 22 dogs had intranasal meningoencephaloceles, usually involving the ethmoidal bone. The same study also noted that some dogs were managed medically with favorable outcomes when tissue protrusion was mild, underscoring that treatment decisions are still individualized rather than protocol-driven. (academic.oup.com)

In the new Animals report, the lesion specifically communicated with the nasal cavity through a cribriform plate defect, which raises concerns beyond seizure control alone. Prior veterinary reports and comparative literature point to the risk of ongoing exposure between the nasal environment and the central nervous system, with potential complications including suspected cerebrospinal fluid rhinorrhea, inflammation, and ascending infection. A 2020 Frontiers in Veterinary Science feline case report made a similar argument for surgery when seizures were progressing and communication with the nasal cavity created concern for liquorrhea and bacterial meningoencephalitis. (mdpi.com)

The available literature also helps put this case in context. The 2020 feline report stated that, at that time, only a dog with intranasal meningoencephalocele and a cat with parietal meningoencephalocele had been described as surgically treated veterinary cases. Earlier canine literature likewise documented surgical treatment of intranasal meningoencephalocele, but the overall evidence base remains sparse. That makes each new operative report useful not just as a novelty, but as a source of technical detail on approach, reconstruction, and short-term outcome. (frontiersin.org)

Expert commentary specific to this new paper was limited in initial web reporting, but the broader specialty literature is fairly consistent on a few points. CT is especially useful for identifying the bony defect, while MRI is better for defining the contents of the lesion and associated brain changes. Human and veterinary reports alike also suggest surgery is most compelling when there is active neurologic progression, suspected CSF leakage, recurrent infection risk, or substantial tissue protrusion into the nasal cavity. That’s an inference drawn from the published case literature rather than a formal guideline, because no veterinary consensus recommendations were identified. (academic.oup.com)

Why it matters: For general practitioners, neurologists, and surgeons, this case is a reminder that not every young dog with seizures has idiopathic epilepsy. When signalment, imaging, nasal signs, or neurologic findings are atypical, congenital skull-base defects belong on the differential list. For referral teams, the report reinforces the value of cross-sectional imaging and suggests that surgery may be reasonable in carefully selected cases, particularly when the lesion creates a direct brain-nasal communication. For pet parents, that can translate into a more precise diagnosis and, in some cases, a treatment path beyond lifelong seizure management alone. (mdpi.com)

What to watch: The field now needs longer follow-up and more case accumulation, especially around recurrence, postoperative seizure control, infection prevention, and reconstruction durability. If more centers publish similar cases, clinicians may start to see clearer patterns on which imaging findings, clinical signs, and lesion anatomies predict the best surgical candidates. (mdpi.com)