Introduction: Following intracerebral hemorrhage(ICH), hematoma expansion leads to worse outcomes. Currently no guidelines exist specifying the quantity and timing of imaging to determine hematoma stabilization in the 24 hours following admission. We investigated the extent to which a third CT scan in this time window is necessary for detecting hematoma-volume fluctuations.
Methods: All patients presenting to the Columbia Neuro-ICU between 02/2009 and 03/2012 were selected. Fifty-two patients received three scans in the acute period. Two patients were excluded due to missing scans. Hematoma volume was assessed by two blinded-reviewers using MIPAV software. Measurements with >30% inter-observer difference were adjudicated by a third author. Error was defined as the absolute value of the inter-observer difference in hematoma volume measurements and its sample mean was used to estimate the expected measurement error. Vol12 was defined as hematoma expansion between the first and second scans, and Vol23 between the second and third scans. Errorvol, Vol12, and Vol23 all followed lognormal distributions, and their sample means were calculated thusly.
Results: The mean Error was 4.33 cm3. For eight patients (16%), ?Vol12 was greater than the expected error. A significantly higher proportion of these patients had hematoma volume growth beyond the expected error between scans 2 and 3 than those with Vol12 < mean Error (3/8=37.5% vs. 2/42=4.8%, p=0.024). A majority (40/50=80%) had no change beyond the expected error.
Conclusions: Our results suggest that the majority of changes in hematoma volume are within the expected measurement error; furthermore, patients with a meaningful expansion on the second scan have a significantly higher chance of showing a meaningful expansion on the third. Further studies are needed to determine whether a third CT scan is of marginal benefit to patients without meaningful expansion on the second scan.
Patient Care: Standardizing the protocols for head CTs and other diagnostic procedures according to case characteristics will result in more efficient and higher quality care for all patients.
Learning Objectives: By the end of this session, participants should be able to discuss the pros and cons regarding the value of a third head CT in the 24 hours following admission.