How Is Stroke Diagnosed?

Stroke is diagnosed through a combination of neurological assessment, brain imaging, and supporting blood tests. At Sunway Medical Centre Penang, our stroke team is available around the clock to carry out rapid assessment and diagnosis the moment a patient arrives.

The goal is to confirm whether a stroke has occurred, identify what type it is, locate which part of the brain is affected, and determine the underlying cause — all as quickly as possible, because every minute without treatment puts more brain tissue at risk.

men having headache

What Tests Are Done When You Have a Stroke?

Diagnosing a stroke involves several tests carried out in quick succession. Brain imaging is the most critical, but blood tests, heart monitoring, and vascular assessment all play important roles in building a complete picture of the stroke and its cause.

1. CT Scan of the Brain

Ischaemic Stroke

A CT scan is almost always the first test performed when a stroke is suspected. It is fast and highly effective at identifying one of the most urgent questions in stroke care: is there bleeding in the brain?

This matters enormously because the three main types of strokes:

Ischaemic stroke – caused by a blocked blood vessel
Haemorrhagic stroke – caused by bleeding

These three types of stokes require completely different treatments. Giving clot-dissolving medication to a patient who is actually bleeding in the brain would be dangerous. A CT scan provides this critical information within minutes.

Beyond ruling out bleeding, a CT scan can also show early signs of brain tissue damage from reduced blood flow, as well as brain swelling and other structural changes.

2. MRI Brain (Magnetic Resonance Imaging)

Haemorrhagic Stoke

An MRI uses powerful magnetic fields and radio waves to produce highly detailed images of the brain. Unlike a CT scan, it does not use radiation. It is significantly more sensitive to early stroke damage and can detect changes in brain tissue within minutes of a stroke occurring, even when a CT scan would not yet show anything abnormal.

When used with a technique called Diffusion-Weighted Imaging (DWI), MRI is considered the gold standard for confirming acute ischaemic stroke. DWI detects the precise area of brain tissue that has been deprived of blood and oxygen, making it especially valuable for identifying small strokes deep within the brain, and strokes in the brainstem or cerebellum, which are very difficult to see on a standard CT scan.

3. MRA Brain (Magnetic Resonance Angiography)

Mini Stroke - Transient Ischaemic Attack

MRA Brain is a specialised type of MRI that focuses specifically on the blood vessels in and around the brain rather than the brain tissue itself. It produces detailed images of the cerebral blood vessels without the use of radiation or contrast dye, making it a safe and non-invasive option for examining vascular structure.

MRA is used to identify narrowed, blocked, or abnormal blood vessels, including aneurysms, which are bulges in a blood vessel wall that carry a risk of rupturing, and arteriovenous malformations (AVMs), which are abnormal tangles of blood vessels that can bleed into the brain. These conditions require specific management and cannot be reliably detected on a standard CT or MRI alone.

MRA is often performed alongside MRI Brain as part of a combined neurological assessment, giving the medical team a complete picture of both the brain tissue and the blood vessels supplying it.

4. Cerebral Angiography

Mini Stroke - Transient Ischaemic Attack

For patients who may need a procedure such as mechanical thrombectomy to remove a clot, cerebral angiography may also be performed. This is a more advanced imaging technique in which a thin, flexible catheter is inserted into a blood vessel in the wrist or groin and guided through to the blood vessels of the brain under live X-ray guidance. A contrast dye is then injected to produce real-time, high-resolution images of blood flow inside the brain.

At Sunway Medical Centre Penang, cerebral angiography is performed by our Consultant Interventional Radiologist inside our Hybrid Catheterisation Laboratory (Cath Lab). This is a specialised facility equipped to both diagnose and treat stroke in the same room, removing any delay between confirming the diagnosis and beginning the intervention.

Supporting Tests That Identify the Cause

Knowing that a stroke has occurred is only part of the picture. Identifying why it happened is equally important, because the cause determines what medication or intervention is needed to prevent a second stroke.

Frequently Asked Questions

Can a stroke be hereditary?

Stroke itself is not directly inherited, but certain risk factors that increase the chance of having a stroke can run in families, including high blood pressure, diabetes, high cholesterol, and certain heart conditions. Having a family history of stroke may mean it is worth discussing your personal risk with a doctor, particularly if multiple close relatives have been affected.

Does stroke always cause permanent disability?

Not always. The outcome of a stroke varies significantly depending on its severity, the part of the brain affected, how quickly treatment was received, and the quality of rehabilitation that follows. Some patients recover fully, particularly after a mild stroke or prompt treatment, while others experience lasting effects of varying degrees. Early treatment and early rehabilitation both play a significant role in maximising recovery.

What part of the brain is most affected by stroke?

This varies from patient to patient, as a stroke can occur in any part of the brain depending on which blood vessel is affected. However, strokes affecting the brain's large hemispheres, particularly areas controlling movement and speech, are commonly seen because these regions are supplied by major arteries that are more frequently involved in both clot-related and bleeding-related strokes.

What is the difference between ischaemic and haemorrhagic stroke?

Ischaemic stroke is caused by a blockage that stops blood from reaching part of the brain, while haemorrhagic stroke is caused by bleeding that damages brain tissue directly and raises pressure inside the skull. Because the two have opposite underlying causes, they require opposite treatment approaches, which is why accurate brain imaging is always carried out before any stroke treatment begins.

Can young people get a stroke?

Yes. While stroke risk increases with age, it is not limited to older adults. Hospital data in Malaysia shows a clear rise in stroke cases among people in their 30s and 40s, often linked to uncontrolled high blood pressure, diabetes, heart conditions, or lifestyle factors. Because stroke is still widely seen as an older person's condition, symptoms in younger patients are sometimes dismissed or mistaken for something else, which can delay urgent treatment.

From Understanding to Action

Understanding what a stroke is, and recognising that it can happen to anyone at any age, is the first step toward acting quickly when it matters most. Knowing the warning signs and how to respond can make a meaningful difference to recovery.

Learn more about stroke care at our Stroke Centre in Penang