Introduction to Hydrocephalus in Pets

Hydrocephalus is a condition characterized by excessive fluid in the brain's ventricles, the fluid-filled spaces within the brain. It's often a congenital condition, meaning pets are born with it. Breeds commonly affected include Chihuahuas, Pugs, Pomeranians, Yorkshire Terriers, English Bulldogs, and several other small breeds.

The accumulation of fluid reduces space for normal brain tissue and can increase pressure inside the skull. This pressure may lead to the death of surrounding brain tissue and, over time, cause the brain tissue to shrink.

Symptoms of hydrocephalus can include seizures, subdued behavior, difficulty with house training, weakness and incoordination, and abnormal vision. While some animals with mild hydrocephalus may lead relatively normal lives, with the condition sometimes discovered incidentally later in life, most symptomatic animals show signs from a young age. However, symptoms can also appear in adult animals.

Diagnosis of hydrocephalus can sometimes be made using ultrasound through the skull, particularly in dogs with large fontanelles (baby "soft spots"). More commonly, diagnosis is achieved through MRI or CT scans, and occasionally, spinal fluid is collected to check for inflammation. As many breeds prone to hydrocephalus are also susceptible to other congenital or acquired diseases, it's important to rule out other conditions before beginning treatment for hydrocephalus.

Note the unusually domed head and thin skull bone in this radiograph.

Treatment

Treatment options include medical and surgical approaches. Medical management involves administering medications to reduce spinal fluid production and decrease inflammation around the brain's dilated fluid pockets. Surgical treatment focuses on enhancing the drainage of fluid from the brain.

Surgical Treatment for Hydrocephalus

Surgical management of hydrocephalus typically involves the placement of a shunt, a tube that redirects fluid from the brain to the abdomen. This procedure continuously drains excess fluid, thereby reducing pressure within the skull. Despite being invasive and costly, shunt surgery is considered the most effective method for draining fluid and protecting the brain.

Surgical intervention tends to be more effective than medical treatment alone in managing hydrocephalus symptoms. While it may not significantly reduce seizure frequency, surgery is more successful in alleviating other neurological issues such as lethargy, confusion, blindness, or difficulty walking.

However, it's important to note that shunt surgery comes with a relatively high risk of complications. Approximately 20-30% of dogs undergoing this procedure may experience issues with their shunt that necessitate further treatment. The most common complication is infection, but others like blockages in the shunt flow can also occur. In some cases, these complications might require shunt replacement, entailing an additional surgical procedure.

Medical Treatment for Hydrocephalus

The medical management of hydrocephalus typically includes medications that reduce fluid production in the brain. Commonly prescribed drugs for this purpose are prednisone, lasix (furosemide), and omeprazole. Additionally, some patients may require seizure medications.

It's important to note that treatment for hydrocephalus is often a lifelong commitment. While patients who undergo surgical intervention may require lower dosages of medication, it is rare for them to completely discontinue medications once they have been deemed necessary.

Monitoring and Regular Veterinary Visits for Hydrocephalus

Regular veterinary check-ups are crucial, particularly in the initial stages of treating hydrocephalus. Pets undergoing medication therapy for this condition should be seen at least twice a year, allowing the veterinarian to monitor for any side effects from the medication.

If your pet exhibits new symptoms or if existing symptoms worsen, it's important to contact your veterinarian promptly. Key symptoms to watch for include: