26 May 2017

Cutting-edge canine epilepsy procedure performed

Tom Harcourt-Brown, veterinary neurologist from Langford Vets (the commercial arm of the University of Bristol's Vet School) and Mike Carter, paediatric neurosurgeon from Bristol Royal Hospital for Children are working in a collaborative effort to combat canine epilepsy, with a treatment typically used on humans.

Langford Vets and Bristol Royal Hospital for Children (BRHC) have joined forces at Langford Vets Small Animal Referral Hospital to implant Vagus Nerve Stimulators into dogs with severe or medically unresponsive epilepsy. The procedure is the first of its type to be undertaken in the UK.

Vagus Nerve Stimulators (VNS) are pacemaker type devices that are commonly implanted in children with medically unresponsive seizures and when other epilepsy surgery procedures aren't suitable. The Paediatric Epilepsy Surgery centre at BRHC implants around thirty of these devices into epileptic children every year. Research work has demonstrated that the technique is effective in other mammals including dogs.

Epilepsy is a very common disorder in dogs and can be very difficult and expensive to treat medically. For this reason many beloved family pets end up being put down when they fail to respond to drugs.  Although VNS is rarely curative of epilepsy in humans or dogs, we are hopeful the surgeries will go some way to help control seizures in dogs with severe epilepsy and enable vets to reduce the amount of medications some dogs are required to take.

Jago, a four year old Border Collie was the first patient at Langford Vets to receive the VNS implant. Before surgery, Jago's seizures had become so frequent that he had difficulty in walking and eating. His device will need regular programming over the next few months to get to optimum settings. If it proves effective, it may be possible to reduce the amount of anti-seizure medications he has to take.

Jago's owner, Mr Leverington said, "Jago is a very important part of our lives and up until he started having seizures he always gave 100% to everything he did. With one medication after another he lost his zing for life, no longer enjoying all that he use to. The VNS implant has allowed us to reduce his medication by almost half and with that we have the old fun loving mischievous Jago back. The transplant has not stopped him from having seizures, but we always knew this would be the case and the ones he does have do not seem to be so severe. At least now we have a chance of controlling the seizures and in some cases stopping them developing. We owe a huge debt of gratitude to Tom Harcourt Brown, Mike Carter and the staff at Langford Small Animal Hospital for giving Jago a fighting chance."

Another of the patients who have since had VNS implanted is four year old Jack Russell Terrier, Eva. Eva had her first seizure two years ago and has since been on a variety of medications with the aim to control her seizures. Eva's owners said, "Whilst her seizures are managed with medication (four different medications, four times per day), her liver has been damaged because of some of the medication, so our hope is that the VNS will enable us to gradually reduce her medication and ultimately be able to either reduce right down, or cut out completely the one that is affecting her liver.

"Typically for Eva, she came home from the surgery after two days, a bright and happy dog, albeit tired.  Apart from a cough, which we are managing, and which is a possible side effect, she is the same affectionate and playful dog we know and adore.

"So far she has still not had any seizures, and we are keeping our fingers crossed that this continues for as long as possible. We wouldn't hesitate to recommend this surgery to anyone, and our hope is that in the future, this can be offered more readily to pet owners.  We now have a lovely "bionic" dog!"

This venture is part of the growing collaborative effort between doctors at University Hospitals Bristol NHS Foundation Trust and Langford Vets, supported by Livanova who manufacture these devices. It is increasingly clear that many treatments used in humans can be very useful in the animal world. Such endeavours also allow a great deal of progress in humans, when treatment measures have first proved successful in animals. Langford Vets and the BRHC have previously worked together on models of brain tumour treatment, cardiac failure, hydrocephalus and now epilepsy. A trend that we very much hope will benefit both human and animal patients in the future.

Tom Harcourt-Brown said: "If a dog's seizures cannot be controlled with medication, there are currently no other treatments available and this can lead to severe cases being put to sleep. Because of this, we are really excited to be working with Bristol Children's Hospital and Livanova to be able to offer Vagal Nerve Stimulation as it is a potentially life-saving treatment in these cases."

Mike Carter said: "Bristol children's hospital is one of four nationally designated services offering surgery for children with drug-resistant epilepsy, and we're the most active VNS service in the country.

"The idea of using VNS to control canine epilepsy started with the observation that many of our patients have dogs, many of which also suffer with epilepsy.

"The results of this collaborative project have so far been very encouraging, and this experience is leading us to consider new ways of using VNS therapy in humans.

"We hope to be able to investigate further surgical techniques that might be beneficial to human and animals alike."

BACK TO NEWS