Every year in the United States, nearly 680,000 people experience the most common form of stroke called ischemic stroke. This occurs when a blood clot restricts blood flow to the brain. For anyone having a stroke, the faster normal blood flow in the brain can be restored, the more likely it is that person will regain a normal life.

For the last two decades, most doctors believed they had only three hours after a stroke to deliver effective treatment. The work of neurologists, neurosurgeons and interventional neuroradiologists at the Stanford Stroke Center, however, has changed this thinking and vastly improved the odds of a full recovery.

New brain imaging techniques and minimally invasive treatments pioneered by these doctors now give stroke patients treated at Stanford a much better chance to return to their normal lives after a stroke.

These advances save mobility and function by:

• Providing a precise, real-time view of what is happening inside each patient’s brain so doctors can quickly assess which parts of the brain have been affected and then deliver more effective, individualized treatment
• Expanding the usefulness of stroke treatment long beyond the time limit once thought possible
• Providing new options for treatment to bring hope to patients once considered untreatable

The Stanford Stroke Center has pioneered the use of brain imaging that is changing the way doctors treat stroke.

Vascular neurologist Greg Albers and his colleagues at the Stanford Stroke Center have long been at the forefront of developing advanced brain imaging and image processing techniques. These techniques are used to examine the brain of each stroke patient at Stanford.

Their most recent imaging advance is a unique software program called RAPID that uses data from MRI and CT scans to track blood flow in the brain. This new imaging platform:

• provides an accurate view of the parts of the brain that have been irreversibly damaged and the parts that can still be saved beyond the standard three-hour treatment window.
• allows doctors to devise individualized treatment options based on each patient’s physiological condition, rather than automatically following a standard treatment protocol.

Ongoing Research to Extend the Treatment Window

Dr. Albers and his research group have also used the new RAPID imaging technology to upend conventional thinking and show that there is wide variability in how stroke affects the brain. Their findings show that:

• Some people’s brains will more easily compensate for loss of blood flow to particular areas. This variation means that for some patients, three hours after a stroke is already too late for effective treatment.
• For others, the treatment window can extend up to 12 hours or longer. Stanford is now leading a large multi-center clinical trial to test whether that window might be as long as 16 hours.

For 20 years, the gold standard for stroke treatment has been a clot-dissolving medicine called tPA — tissue plasminogen activator. This substance can often restore blood flow if clots are small and the medication is given early, however, it has limited success for large clots.

Six of 10 patients do not respond to tPA, so other treatment options have been developed. Some stroke patients have been helped by a catheter-based treatment that sends tiny mechanical devices into the brain to physically remove the clot.

Stent Retriever: An Important New Option for Stroke Care

Stanford’s stroke doctors were among the first in the United States to test the next-generation solution called a stent retriever. The stent retriever has shown it can unblock blood vessels affected by stroke up to six hours afterwards.

The Stanford Stroke Center was the first hospital in Northern California to combine the stent retriever and patient selection strategies for regular clinical use.

Recent studies that combined the new Stanford imaging techniques and the stent retriever reported the best outcomes ever achieved for treatment of stroke-- favorable outcome rates as high as 71%.