The committee also highlighted that any increase in MRI requests may be small because the decision to perform an MRI will not generally be affected by the results of a previous CT scan. The committee recognised that if there was an increase in MRI requests, this could be a challenge because access to high-quality MRI scanners is limited in some trusts. In 2022 addition, there are limits on the number of MRI slots per day, so there may be a need for dedicated MRI slots for people with suspected TIA. Return to recommendations Thrombectomy for people with acute ischaemic stroke Why the committee made the recommendations Anterior circulation stroke Overall, the evidence across timeframes showed that thrombectomy, with or without thrombolysis, improved functional outcome as measured by the modified Rankin Scale (mRS) in people last known to be well up to 24 hours previously, compared with usual care. There was also a potential benefit for improved quality of life. However, there was no clinical difference in mortality and there were low rates of symptomatic intracerebral haemorrhage. The committee noted there had been some procedural complications associated with thrombectomy, but agreed that these were outweighed by the benefits of improvement in functional outcome. The committee looked at the results of 2 published cost utility analyses with a UK NHS perspective. The first estimated that thrombectomy alongside intravenous thrombolysis (when appropriate) is cost effective compared with intravenous thrombolysis alone, when performed within 6 hours of stroke onset (that is, from when a person was last known to be well). The second demonstrated the cost effectiveness of thrombectomy therapy and best medical therapy compared with best medical therapy alone, when performed 6 to 24 hours after stroke onset. 