Early quantitative CT perfusion parameters variation for prediction of delayed cerebral ischemia following aneurysmal subarachnoid hemorrhage

To prospectively evaluate the predictive value of cerebral perfusion-computerized tomography (CTP) parameters variation between day0 and day4 after aneurysmal subarachnoid haemorrhage (aSAH). Mean transit time (MTT) and cerebral blood flow (CBF) values were compared between patients with delayed cerebral ischemia (DCI+ group) and patients without DCI (DCI- group) for previously published optimal cutoff values and for variations of MTT (Delta MTT) and of CBF (Delta CBF) values between day0 and day4. DCI+ was defined as a cerebral infarction on 3-months follow-up MRI. Among 47 included patients, 10 suffered DCI+. Published optimal cutoff values did not predict DCI, either at day0 or at day4. Conversely, Delta MTT and Delta CBF significantly differed between the DCI+ and DCI- groups, with optimal Delta MTT and Delta CBF values of 0.91 seconds (83.9 % sensitivity, 79.5 % specificity, AUC 0.84) and -7.6 mL/100 g/min (100 % sensitivity, 71.4 % specificity, AUC 0.86), respectively. In multivariate analysis, Delta CBF (OR = 1.91, IC95% 1.13-3.23 per each 20 % decrease of Delta CBF) and Delta MTT values (OR = 14.70, IC95% 4.85-44.52 per each 20 % increase of Delta MTT) were independent predictors of DCI. Assessment of MTT and CBF value variations between day0 and day4 may serve as an early imaging surrogate for prediction of DCI in aSAH. aEuro cent CT perfusion values are an imaging surrogate for prediction of DCI. aEuro cent Early variations (day0-day4) after aneurysmal subarachnoid haemorrhage predicted DCI. aEuro cent A CBF decrease of 7.6 mL/min/100 g predicted DCI with 100 % sensitivity. aEuro cent An MTT increase of 0.91 seconds predicted DCI with 83.9 % sensitivity. aEuro cent DCI risk multiplied by 2 per 20 % Delta CBF decrease and by 15 per 20 % Delta MTT increase.