Purpose
The CT angiography (CTA) spot sign is a strong predictor of hematoma expansion in intracerebral hemorrhage (ICH). However, CTA parameters vary widely across centers and may negatively impact spot sign accuracy in predicting ICH expansion. We developed a CT iodine calibration phantom that was scanned at different institutions in a large multicenter ICH clinical trial to determine the effect of image standardization on spot sign detection and performance.
Methods
A custom phantom containing known concentrations of iodine was designed and scanned using the stroke CT protocol at each institution. Custom software was developed to read the CT volume datasets and calculate the Hounsfield Unit as a function of iodine concentration for each phantom scan. CTA images obtained within 8 h from symptom onset were analyzed by two trained readers comparing the calibrated vs. uncalibrated density cutoffs for spot sign identification. ICH expansion was defined as hematoma volume growth >33%.
Results
A total of 90 subjects qualified for the study, of whom 17/83 (20.5%) experienced ICH expansion. The number of spot sign positive scans was higher in the calibrated analysis (67.8% vs 38.9% p<0.001). All spot signs identified in the non-calibrated analysis remained positive after calibration. Calibrated CTA images had higher sensitivity for ICH expansion (76% vs 52%) but inferior specificity (35% vs 63%) compared with uncalibrated images.
Conclusion
Normalization of CTA images using phantom data is a feasible strategy to obtain consistent image quantification for spot sign analysis across different sites and may improve sensitivity for identification of ICH expansion.
Background/Purpose:
The ICH score (ICHS) is commonly used to predict 30-day mortality in spontaneous ICH. Several investigators have evaluated additional factors in an attempt to refine this score, though none of these modifications have been incorporated into routine practice. We sought to determine whether incorporating additional radiographic features, specifically herniation and/or the degree of midline shift (MLS), improved the performance of the ICH score.
Methods:
We retrospectively reviewed 180 consecutive ICH patients admitted to a single comprehensive stroke center between September 2014 and November 2015. The outcome of interest was poor prognosis, defined as mRS of 4-6, at time of discharge. Admission head CTs were evaluated by a vascular neurologist to determine whether uncal, tonsillar or subfalcine herniation were present, and to quantify the degree of midline shift. Midline shift was treated as a categorical variable determined by measuring the shift of the septum pellucidum from midline at the level of the basal ganglia.
Results:
Patients with radiographic herniation present on admission had a much higher odds of poor outcome; however, this measure was specific (98%) but not sensitive (23%). Degree of midline shift performed similarly, with a specificity of 86% and a sensitivity of 36%. In our population, the ICH score was a better predictor of poor outcome than any of the combinations shown in the Table. For each unit increase in ICH score, the odds of a poor outcome increased by a factor of 2.6.
Conclusion:
Although clinicians often view radiographic evidence of herniation and midline shift as indicators of dire prognosis, incorporation of these features into a modification of the ICH score failed to improve upon the original scale.
Background and Objective:
Transcranial Doppler (TCD) is endorsed by the American Heart Association/American Stroke Association, the American Academy of Neurology, and the Neurocritical Care Society for use in aneurysmal subarachnoid hemorrhage (aSAH) for surveillance of cerebral vasospasm (CV). However, data on utilization of TCD for CV detection and monitoring in aSAH are lacking. We estimated the proportion of patients with aSAH receiving TCD monitoring using the Nationwide Inpatient Sample (NIS).
Methods:
Data from 2002-2011 NIS were used to calculate the number of discharges with a primary diagnosis of aSAH per 100,000 discharges. Descriptive analysis of nationwide trends in TCD prevalence was performed. Teaching hospitals were examined separately for TCD utilization rates and this was done biennially to prevent small numbers.
Results:
Between 2002 and 2011, a total of 256,089 patients were discharged with a diagnosis of aSAH of which 3,850 underwent TCD monitoring. aSAH accounted for an average of 67.1 discharges per 100,000 annually (95% CI 61.3-72.8) from 2002-2011. Of these, only 1.5% (95% CI 0.4-2.6) underwent TCD examination. In teaching hospitals, aSAH accounted for an average of 108.5 discharges per 100,000 biennially (95% CI, 96.2-120.8), of which 2% (95% CI 1.0-4.0) underwent TCD examination. TCD utilization increased from <1% during the 2002-2005 period, to ≥1.5% during the 2006-2011 period (OR 2.3, 95% CI 1.0-5.7), an increase also seen in teaching hospitals.
Conclusion:
TCD is underutilized nationally in the care of aSAH. While the prevalence of TCD is low in teaching hospitals, it is nearly nonexistent in non-teaching hospitals.
Background and Purpose:
Cerebral edema is known to contribute to clinical decline in patients with spontaneous ICH. We sought to evaluate the significance of cerebral edema on outcome in young patients with primary ICH.
Methods:
We performed a retrospective review of patients presenting to our CSC center from 2014-2015 with primary ICH, excluding patients with lobar ICH and age 55 and above. Patients were grouped according to functional outcome at discharge (mRS 0-3 vs. 4-6). Imaging characteristics of those with poor short-term functional outcome (mRS 4-6) were compared to those with mRS 0-3. Receiver Operating Characteristics curves were used to evaluate the discriminatory ability of imaging characteristics with regards to poor functional outcome.
Results:
A total of 38 patients met inclusion criteria (mean age 47, 42% black, 55% male). On presentation, patients with poor functional outcome had larger mean ICH volume (26 vs 9cc; p=0.020), higher ICH volume to edema volume ratios (2.0 vs. 0.7, p=0.010), more evidence of midline shift (38% vs. 6%, p=0.026), and IVH (52% vs. 17%, p=0.043). Groups did not differ in terms of edema volume, amount of midline shift, evidence of hydrocephalus, or herniation. ICH volume to edema volume ratio was a better discriminator of poor outcome (AUC=0.813, p=0.006) than ICH volume (AUC=0.802, p=0.008, Figure 1a). Further, ICH volume to edema volume ratio was a better discriminator of poor outcome (AUC=0.801, p=0.009) than ICH score (AUC=0.724, p=0.051, Figure 1b).
Discussion:
Among young patients with non-lobar primary ICH we observed that the ICH to edema ratio was a better predictor of poor functional status at discharge than ICH volume or ICH score.
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