Teenage boy survives rare brain aneurysm thanks to expert team at Southampton Children's Hospital

A teenage boy who suffered a rare brain aneurysm has survived against the odds thanks to an expert medical team at Southampton Children’s Hospital (SCH).

Warrick Allon’s parents were told to prepare for the worst as he was rushed into emergency surgery to try and reduce the immense pressure in his skull following a brain haemorrhage.

He survived the surgery but was left unable to talk, walk or eat after developing a syndrome common with such invasive surgery close to the brain.

But now, thanks to the expertise of surgeons and a specialist neurological rehabilitation team at SCH Warrick, is able to walk and communicate again – and has even returned back to school part-time.

Warrick, 15, from Andover, started to complain of a headache while at home with his mum Krissie Thatcher and stepdad Paul Thatcher on April 7 – minutes later he collapsed and was unresponsive. The Winton Community Academy schoolboy was rushed by ambulance to Southampton Children’s Hospital.

Scans showed he had an arteriovenous malformation (AVM) - an abnormal tangle of blood vessels - that had ruptured causing a large blood clot to form and bleed on his brain.

Aabir Chakraborty, neurosurgeon at Southampton Children’s Hospital, led the team in the emergency operation to reduce the pressure build-up, which included draining fluid that was surrounding the brain and removing the blood clot and some of the abnormal vessels that had caused the haemorrhage.

The operation also involved removing part of Warrick’s skull, which was stitched into his back during surgery to allow for the swelling around the brain to reduce and to preserve the bone.

Mr Chakraborty said: “I could see that this was an unusually large blood clot that had caused considerable pressure around Warrick’s brain stem, the lower part of the brain that is connected to the spinal cord.

“I was very concerned that he was at high risk of imminent brain death, and so it was imperative we got him into surgery as quick as possible”

“He had an excessive amount of bleeding which made this a difficult operation to perform. The first task was to insert an external ventricular drain, a device which allows for the drainage of excess fluid on the brain, in the front of his skull to reduce the pressure in his head.

“Once we had secured the drain, we continued with tackling the blood clot which involved removing a part of Warrick’s skull to help reduce the swelling at the back of his head.

“We were forced to remove some of the abnormal blood vessels as they were bleeding profusely.”

After six hours in surgery, Warrick was placed in recovery – the surgical team had successfully removed the blood clot and half of the AVM.

Mum Krissie said: “I will remember that moment forever. We asked what Warrick’s chances of survival were and were told it was 50/50.

“It all happened so quickly but I remember telling Mr Chakraborty that my boy wasn’t going to die. It wasn’t denial, it was determination – he wasn’t going to die that day.”

For the next few days Warrick remained in an induced coma but, with the help of bedside testing and an MRI scan, the surgical team were confident that his brain stem was working and hadn’t been irreversibly damaged. However, when Warrick woke, he was unable to speak or move.

It quickly became clear that he was suffering with Posterior Fossa Syndrome (PFS) – a rare condition which can sometimes develop after brain surgery to the base of the skull that contains the cerebellum and brain stem.

Usually associated with children who have had a tumour removed from their cerebellum, PFS can cause long lasting effects in children including loss of muscle tone, memory trouble, unsteadiness and decreased ability to talk.

It was vital that Warrick began rehabilitation straight away.

The Southampton Children’s Integrated Rehabilitation Team [SCIRT] is a specialist service at SCH that runs alongside a child’s medical and surgical needs. Southampton is just one of a handful of children’s hospitals in the UK that has such a unique rehabilitation service, enabling rehab to begin at the earliest stage of recovery, even while in a paediatric intensive care unit.

Shona Mackie, paediatric neurology nurse specialist at SCH, said: “We are very lucky to have access to such a fantastic neurorehabilitation service.

“Research shows that patients make better progress when rehabilitation begins at the earliest opportunity and reduces the length of their hospital admission.

“We are also unique in that we are also able to offer our service seven days-a-week including bank holidays for suitable patients.”

Warrick’s rehabilitation started while he was still in intensive care – a bespoke neuro-rehabilitation regime was tailored, gradually extending sessions as he was able and ensuring he was always being gently challenged.

Initially Warrick was unable to talk, walk or move easily but, after just two weeks, he was able to sit in a chair for 10 minutes. After three months he was eating, speaking fluently, and walking slowly.

Ms Mackie added: “Warrick’s case is quite rare, in fact we’ve only seen two similar cases in over 20 years here in Southampton, which makes his progress even more outstanding.

“When a patient is so profoundly affected by PFS we would expect progress to take much longer but, with our fantastic team along with Warrick’s sheer will and determination as well as his family’s dedicated support, he has exceeded all of our expectations.”

Warrick has since undergone two further operations. The second operation took place on 12 May, one month after his emergency surgery, to remove the remaining AVM and reattach his skull flap. The final surgery was on 9 June to insert a shunt to treat the excess build-up of cerebrospinal fluid (CSF), otherwise known as hydrocephalus.

Having astounded medics with his recovery, Warrick has now returned home and is back at school part-time. He will continue his outpatient rehabilitation programme, with the ultimate aim of taking his GCSE exams and attending college in 2023.

Warrick’s Dad, Dave Allon, who lives in Andover with his wife Lisa, said: “We can’t thank Mr Chakraborty and the amazing team at Southampton Children’s Hospital enough.

“What they have done is nothing short of miraculous, they didn’t just save his life, they have returned him home to us and we will be forever grateful for that.”

Mr Chakraborty continued: “I am so happy to see how far Warrick has come – he really has survived against the odds.

“He and his family are some of the most remarkable people I have ever met. I look forward to seeing his positive progress.”