Stroke, often mistakenly viewed as something that only happens to the elderly, can strike at any age, with profound consequences. We spoke with Dr Hofmeyr Viljoen, a Neuroradiologist from SCP Radiology, to understand this critical health issue, from its causes to the cutting-edge imaging that guides life-saving care.

To start, could you demystify what a stroke is and its main forms?

‘A stroke is essentially a ‘brain attack’, the brain’s equivalent of a heart attack. It occurs when the blood supply to a part of the brain is suddenly cut off or significantly reduced. Without this vital oxygen and nutrient supply, brain cells in the affected area begin to die within minutes.’

There are two primary types:

Ischemic stroke: The most common, caused by a blockage, usually a blood clot, in an artery supplying a part of the brain.

Rupture and bleeding in the brain (haemorrhagic stroke): Occurs when a brain blood vessel ruptures and bleeds. The blood can damage brain tissue and result in a dangerous increase in pressure in the skull. It usually presents with sudden, severe headache and associated weakness on one side.

F = Face drooping: One side may droop or feel numb.
A = Arm weakness: One arm may be weak or numb.
S = Speech difficulty: Speech may be slurred or the person might be unable to speak or understand.
T = Time to call emergency services. If you observe any of these signs, call for emergency help immediately.

Other critical red flags include sudden numbness, confusion, vision problems, dizziness and loss of balance. These need immediate attention.

How common is stroke in young adults, why is it such a significant concern?

‘While statistically less common than in older patients, strokes occurring before the age of 50 can be devastating, robbing young people of decades of healthy life,’ says Dr Vijoen. The personal, familial and societal costs are enormous.

‘In regions like South Africa and sub-Saharan Africa, we’re seeing rising stroke rates and it’s a leading cause of adult mortality. Conditions prevalent in younger populations here, such as HIV, an independent risk factor, increase stroke odds more than five-fold. Studies show African stroke patients with HIV are much younger. In South Africa, we frequently encounter stroke patients in their 20s to 40s with underlying HIV or other risk factors less typical in Western cohorts.’

Why do young people have strokes?

For older individuals, strokes are usually a result of poorly controlled high blood pressure and build-up of plaque in the arteries (atherosclerosis), due to the usual risk factors of smoking, diabetes, high cholesterol and family history. But, in younger people those common risk factors only account for 15-25% of cases.

Other, less typical causes are often involved, including:

• Clots: About 20% of strokes in young adults happen when a blood clot travels to the brain, usually originating in the heart.
• Artery tear (dissection): Sometimes, a small tear can form in a blood vessel in the neck or head, often after a minor injury or sudden neck manipulation. This causes up to 20% of strokes in young people.
• Blood clotting disorders: Some people have genetic diseases that make their blood more prone to clotting.
• Inflammation or infection of blood vessels:
  o HIV: Is a major concern, can damage blood vessels and increase the risk of clots
  o TB: Can cause inflammation in the brain’s small blood vessels, leading to several small strokes.
• Drug use: Stimulants like cocaine or methamphetamine are well known causes of stroke in young patients, causing blood vessel inflammation and spasm.
• Other risk factors are pregnancy and the first few weeks after giving birth, oral contraceptive use and cancers, all due to increasing clotting risk.

‘For a young stroke patient, our diagnostic checklist includes ruling out a tear or inflammation of blood vessels, searching for heart sources of clots, testing for clotting disorders and investigating infections like HIV or TB, alongside traditional vascular risk factors.’

How is a stroke diagnosed in the emergency setting and what’s the radiologist’s precise role?

‘Rapid, accurate diagnosis is key and neuroimaging is central. Our job is to determine if it’s ischemic or haemorrhagic, locate blocked vessels, assess brain damage and salvageable tissue,’ explains Dr Viljoen.

A radiologist’s typical imaging includes:

1. Non-contrast CT of the head: This is fast, widely available and excellent for detecting a haemorrhage and ruling out mimics. If there is no bleeding, an ischaemic stroke is suspected.
2. CT Angiography (CTA) is often performed if no bleed is detected. Contrast (iodine based radiographic dye) is injected into an arm vein during the scan and circulates through the body. It highlights the head and neck blood vessels, pinpointing clots, vessel narrowing and tears. CTA can also reveal bleeding aneurysms and vascular malformations in the setting of haemorrhagic stroke.
3. MRI is very accurate in detecting stroke. However, this is less commonly used in the acute setting due to the much longer scan times and limited availability, especially after hours. MRI is usually reserved for problem solving where the diagnosis of ischaemic stroke is unclear.
4. Digital Subtraction Angiography (DSA) is a more invasive angiogram where the contrast is directly injected into the neck arteries. DSA gives highly detailed images of blood vessels, nowadays mostly done as part of treatment to remove a clot or open up a narrowed blood vessel.

‘Imaging is the radiologist’s toolkit. We interpret scans rapidly to confirm stroke type, measure extent, identify the problem artery and flag complications’, says Dr Viljoen. ‘Improved neuroimaging access, leads to better outcomes and timely treatments.’

Finally, what proactive steps can young people take to reduce their stroke risk?

Up to 80% of strokes are preventable:

• Know and control your numbers. Regularly check and manage blood pressure, blood sugar and cholesterol
• Manage infections. Get tested for HIV and TB. If positive, adhere to the treatment protocols. Effective HIV therapy reduces associated stroke risk
• Embrace a healthy lifestyle. Don’t smoke, avoid or limit alcohol intake, steer clear of illicit stimulant drugs and maintain a healthy weight through balanced diet and regular physical activity.

There are some special considerations too.

• If you have a known clotting disorder or heart condition, work with your doctor on preventative strategies
• Women who smoke should be cautious with oestrogen-containing oral contraceptives.

Dr Viljoen emphasises that it is important to know and recognise symptoms, to act F.A.S.T. and to call emergency services immediately if you suspect you or someone is having a stroke.

The take-home message: Stroke is not exclusively an ‘old person’s disease.’ Being aware that it can affect young adults, understanding modern imaging’s power in diagnosis and the importance of preventative measures are vital for saving lives.