HHE Neurology supplement 2018 | Page 14

Stroke diagnostic pathway and patient selection A neurological examination is performed on all patients with suspected hyperacute stroke. National Institutes of Health Stroke Scale (NIHSS) score is performed at the time of admission by the stroke team. Patients presenting with NIHSS ≥6 and within six hours of symptom onset for anterior circulation stroke or 12 hours for posterior circulation strokes are considered for mechanical thrombectomy. As per the NCCCC guidelines, 9 plain CT of the brain is performed immediately to exclude patients with contraindications to treatment, such as acute haemorrhage or significant established ischaemia. For middle cerebral artery territory symptoms, the Alberta Stroke Program Early CT Score (ASPECTS) is performed to assess the degree of established ischaemia. Patients with a lack of extensive early ischaemic change (those with ASPECTS more than 5 on plain CT) are selected. 8 If there are no contraindications to treatment, then a CT angiogram is performed from aortic arch to the vertex. This helps to delineate the vascular anatomy and assess the patency of the intracranial arterial system, as well as the degree of collateral supply. In patients with uncertain time of symptom onset, brain perfusion imaging (CT or MRI) may be employed. 8 The decision to proceed with mechanical thrombectomy is made in conjunction with a stroke physician considering the patient’s clinical condition, age and co-morb