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Hidden Stream: The Untold Story of a CSF leak 

Premieres on YouTube on 3 December 2025

The CSF Leak Association has launched a compelling new 30-minute documentary on World Disability Day (3rd December), highlighting the often-underdiagnosed and rare condition of spontaneous Cerebrospinal Fluid (CSF) Leaks.

This educational film - Hidden Stream: The Untold Story of a CSF Leak - follows the remarkable journey of Dr Bernadette Herd, a GP from Rudry, south Wales, who suffered a spontaneous CSF leak while on a work trip to Malta in 2023.

CSF is a clear liquid contained within a membrane that surrounds the brain and spine. It nourishes, cleanses and cushions the brain and spinal cord.

A CSF leak occurs when this membrane is breached, allowing the fluid to escape. This can cause severe headaches, dizziness and nausea, with the pain often worsening when sitting or standing.

Dr Bernadette’s story serves as a powerful reminder of the debilitating and painful nature of the condition and the need for increased research, funding, and support - particularly for patients in rural areas who face barriers to diagnosis and treatment.

 “I first felt this jolt in my neck and thought ‘Oh, I’ve twinged something,’ Dr Bernadette revealed.

She added, “But within minutes, there was this horrendous sense that my brain was heavy, like wet cement sliding to the base of my neck.”

The programme captures her ordeal, including the month she spent in hospital Malta, where she underwent three MRIs and was diagnosed with a CSF Leak. After Dr Bernadette returned to the UK, it took almost a year to achieve a precise diagnosis.

Following a complex spinal repair surgery at London’s National Hospital for Neurology and Neurosurgery in Queen Square - after months of battling to secure NHS funding as this type of surgery was unavailable under NHS Wales - Dr Bernadette made a full recovery from her CSF leak and has since been able to continue enjoying an active lifestyle of running, horse riding, and paddleboarding.

But she knows many others are not so fortunate.

Dr Bernadette explained, “I was lucky. I’m a GP, my husband also works in medicine, and we could afford to go private when we had to. Most people can’t. I’m speaking out and working with the CSF Leak Association to fight for more awareness, better access to diagnosis and care in rural areas, and urgently-needed research funding.”

The documentary also features two specialists involved with Dr Bernadette’s journey: consultant neurosurgeon at National Hospital for Neurology and Neurosurgery, Mr Parag Sayal, and also consultant neuroradiologist at the same hospital, Dr Indran Davagnanam.

Spontaneous CSF leaks are estimated to affect 3.8 per 100,000 people annually in the UK – with roughly 2,500 new cases each year.

Women between the ages of 30 and 40 are particularly at risk. The symptoms are frequently mistaken for other conditions such as chronic migraines, leading to misdiagnosis or delayed treatment. Left untreated, CSF leaks are associated with serious complications including brain bleeds, superficial siderosis and even early-onset dementia.

CSF leaks can occur spontaneously, or be triggered by trauma (such as a car accident) or medical procedures like spinal taps or epidurals.

The CSF Leak Association is using this documentary to raise awareness and advocate for more research. Funding is especially needed to support those in remote or underserved areas, where patients often face longer waits, fewer specialists, and limited access to advanced imaging and surgical care.

Clare Joy, Chair of CSF Leak Association said:

“CSF leaks are curable yet people with CSF leaks endure months or even years of severely disabling symptoms, dismissal and misdiagnosis, leading to ineffective or harmful treatments. “Lack of awareness about the condition and the clinical guideline means outcomes vary dramatically depending on where a patient lives, prolonging needless suffering in those denied access to effective treatments.”