Educational Series

This is the VALIDATE educational series, where we explain Acute Ischemic Stroke (AIS) and Artificial Intelligence (AI) in healthcare  related topics.

What is Acute Ischemic Stroke?
Acute Ischemic Stroke (AIS)
An ischemic stroke is the sudden loss of blood circulation to an area of the brain, that is caused by a thrombotic (formed in the brain) or embolic (formed elsewhere in the body) occlusion. This blockage prevents the affected area of the brain from receiving oxygen which damages the cells. AIS are the most common form of stroke.
AIS
Over 1 million people in the EU suffer a stroke each year. The treatment needs to be fast and optimal to avoid neurological damage. Current treatment methods work well, but an accurate assessment of different treatment methods is challenging.
AIS vs. Hemorrhagic
In an ischemic stroke the damage is caused by an obstruction reducing or even stopping the blood supply to the affected area in the brain. There is another type of stroke, the hemorrhagic stroke, in which the damage is caused by bleeding into brain tissue. Both types of stroke require immediate medical attention.
Time is Brain!
1.9 Million brain cells die every minute
during acute ischemic stroke. A clot prevents the brain from receiving oxygen and cells begin to die. This leads to irreversible damage in the affected area, causing paralysis or the loss of functions such as speech and vision.
Time is Brain
An acute ischemic stroke is a medical emergency and should be treated as fast as possible. Fast treatment saves brain cells from dying, reducing the chance of death or disability. As you get older brain cells die naturally, during a stroke those cells die rapidly, accelerating the aging of the brain.
Artificial Intelligence in Stroke Care
AI in health care
Artificial Intelligence can improve health care, as it can be applied in various fields, ranging from early detection and diagnostics of diseases, robots assisting physicians in surgeries, to personalised treatment plans. AI can also be used to support medical documentation, freeing up time that physicians can spend with their patients instead.
AI in stroke care
In stroke care AI is already being used to analyse CT and MRI scans of stroke patients. Imaging-based AI software can localise the area in the brain that is affected by the stroke and help determine which type of stroke (ischemic or haemorrhagic) it is.
AI in stroke care
The AI can analyse the images faster than a physician could, saving time. And in the case of stroke time is crucial, as every minute counts. The sooner a stroke is treated, the better are the potential health outcomes of patients.
Trustworthy AI
Trustworthy AI are AI-models based on ethical guidelines and have privacy and data protection. These AI-models need to be safe, transparent, and robust.
How are Ischemic Strokes Treated?
Intravenous Thrombolysis (IVT)
For patients with stroke within 4.5 hours since symptom onset or patients who awoke with stroke and have last been seen well less than 4.5 hours ago, intravenous thrombolysis is used to dissolve the clot with medication. This restores bloodflow in the affected area in the brain, preventing death.
Endovascular Thrombectomy (EVT)
This is a procedure that removes the clot blocking an artery in the brain through a minimally invasive surgery. A catheter is inserted in an artery in the groin and then guided up through the blood vessels until it reaches the obstruction. There a stent retriever grabs and removes the clot, restoring blood flow.
IVT and EVT
IVT is often administered before EVT. Each stroke case is different, so there are patients who do not qualify to receive both. Additionally, the hospital at which the stroke patient is treated affects which treatment is administered. EVT requires special equipment and trained staff, and is usually only performed at stroke specialised centers.
Stents in Stroke Care
Narrowed arteries are a stroke risk
With age arteries become narrower as they lose flexibility and plaque can build up on the lining of arteries, which is known as atherosclerosis. Due to narrowed arteries blood clots can develop.
Narrowed arteries are a stroke risk
The clots can block the arteries entirely or break off and travel to the brain, which causes a stroke. So, the risk of stroke is increased the narrower the arteries, especially the carotid arteries, are.
To improve blood flow a stent is implanted. A stent is a small metal-mesh tube that provides structural support to the artery, preventing it from collapsing or becoming blocked off again.
Stents
The stent is inserted with a catheter through an artery in the groin. Once it has reached the location of the blockage it is inflated with the help of a balloon. Metal-mesh stents are a life-long implant. For temporary usecases like assisting arteries with healing biodegradable stents that dissolve after being inside the body for a certain time exist. But those are typically not used to treat and prevent strokes.
Stroke Units in Hospitals
Stroke Unit (SU)
A hospital’s Stroke Unit is specialised in the diagnosis, care and treatment of strokes. SUs have highly trained doctors, nurses, physiotherapists and speech therapists that offer the best care for stroke patients.
Stroke Unit (SU)
Due to specialised treatments SUs reduce the risk of disability and death compared to a normal hospital ward. However, not every hospital has a SU. Especially smaller or regional hospitals tend to lack the specialised equipment and staff needed for SUs.
Mobile Stroke Unit (MSU)
A mobile stroke unit is an ambulance with special equipment and is exclusively used for potential stroke patients. MSUs have a mobile CT scan and blood analysis devices on board. This allows the first responders to verify if a suspected stroke patient is having a stroke and to start treatment.
Mobile Stroke Unit (MSU)
That way IVT can for instance be administered before the patient reaches the hospital. Using MSUs in stroke care leads to overall better treatment of AIS and can help reduce disability as the stroke is treated faster.
Untreated Stroke
Untreated Stroke
During a stroke about 1.9 million brain cells die every minute. If treatment is delayed or a stroke is left untreated it can lead to serious disabilty or even death.
Untreated Stroke
People who have a stroke while they are sleeping are more likely to have complications, as it is difficult to determine when the stroke happened. In case of symptoms of stroke timely treatment is essential to reduce the risk of disability.
Possible long-term complications of stroke
  • memory loss
  • vision issues
  • speech difficulty
  • mood changes
  • paralysis or weakness
  • fatigue
  • loss of coordination
  • pain