In a brain infarct or stroke, damage occurs because a part of the brain no longer has a blood supply. Often the cause is a blood clot that occludes the blood vessel. The longer the occlusion exists, the greater the brain damage will be. So it is always important to act as soon as possible from the first symptoms. With the MR CLEAN study, the research group showed back in 2015 that the clot can be removed from the blood vessel by means of a catheter advanced through the groin to close to the clot in the brain (endovascular treatment) and that this was safe and effective up to six hours after the onset of symptoms.
The effectiveness of endovascular treatment decreases with increasing time between the onset of symptoms and starting treatment. Previous research showed that treatment was more effective in patients with 'collaterals' (blood vessels supplying the affected area with some blood via bypasses) than in patients where less good or no collateral filling was seen. The aim of the MR CLEAN-LATE study was therefore to investigate whether endovascular treatment of cerebral infarction would still be effective and safe even in the "late time window" (defined as 6 to 24 hours after the onset of symptoms or the time when patient was last symptom-free) for patients selected on the basis of collateral filling present on the CT scan.
The MR CLEAN-LATE study showed that patients with cerebral infarction who presented in the late time window and were selected on the basis of having collaterals on CT had a beneficial effect of endovascular treatment. The positive outcome mainly translated into improved functioning and quality of life. Patients in the treatment group had significantly fewer impairments after three months than the untreated group. Neurologist Maarten Uyttenboogaart notes that through this study, more patients will be eligible for treatment of cerebral infarction, enabling improvements in quality of life to be achieved for a significant group of people who have suffered a stroke.
