Objective: To explore the diagnostic valves of computed tomography perfusion imaging (CTP) in hyperacute cerebral infarction patients and examine the correlation of time period from symptom onset to examination and CTP parameters.
Methods: Non-enhancement CT and CTP were performed on 75 patients with acute cerebral infarction of internal carotid system within 8 hours of symptom onset at our department from January 2006 to May 2008. National Institute of Health Stroke Scale score (NIHSS), Barthel index (BI) and modified Rankin scale (mRS) were assessed at the same day, days 14 and 90 after stroke onset respectively for neurological function impairment, activity of daily living and extent of disability in prognosis.
Results: (1) All CTP parameters in ischemic region had no correlation with time period from symptom onset to examination (P > 0.05). No significant differences were found between the patients with > 3 hours and < 3 hours after stroke onset in terms of the above parameters; (2) the areas of CBF (cerebral blood flow) on ischemic region significantly correlated with NIHSS at the day of symptom onset (r = 0.391, P < 0.001), Day 14 (r = 0.564, P < 0.001) and Day 90 (r = 0.549, P < 0.001) after symptom onset. CBV (cerebral blood volume) and TTP (time-to-peak) on ischemic region significantly correlated with the evaluation indices of predicting clinical outcomes at the day of symptom onset, Days 14 and 90 (P < 0.01). CBF, CBV, rCBF (regional CBF) and rCBV (regional CBV) correlated only with some of the clinical outcome scores.
Conclusion: Time period after symptom onset can not reflect the ischemic extent and volume of cerebral infarction. But CTP may evaluate the severity and prognosis of acute cerebral infarction patients. The area of abnormal perfusion is the most sensitive parameter.