Stroke Research Priorities for the Next Decade – A Supplement Statement on Intracranial Haemorrhage

Quantitative CT densitometry for predicting intracerebral hemorrhage growth

BACKGROUND AND PURPOSE

Intracerebral hemorrhage growth independently predicts disability and death. We hypothesized that noncontrast quantitative CT densitometry reflects active bleeding and improves predictive models of growth.

MATERIALS AND METHODS

We analyzed 81 of the 96 available baseline CT scans obtained <3 hours post-ICH from the placebo arm of the phase IIb trial of recombinant factor VIIa. Fifteen scans could not be analyzed for technical reasons, but baseline characteristics were not statistically significantly different. Hounsfield unit histograms for each ICH were generated. Analyzed qCTD parameters included the following: mean, SD, coefficient of variation, skewness (distribution asymmetry), and kurtosis ("peakedness" versus "flatness"). These densitometry parameters were examined in statistical models accounting for baseline volume and time-to-scan.

RESULTS

The coefficient of variation of the ICH attenuation was the most significant individual predictor of hematoma growth (adjusted R(2) = 0.107, P = .002), superior to BV (adjusted R(2) = 0.08, P = .006) or TTS (adjusted R(2) = 0.03, P = .05). The most significant combined model incorporated coefficient of variation, BV, and TTS (adjusted R(2) = 0.202, P = .009 for coefficient of variation) compared with BV and TTS alone (adjusted R(2) = 0.115, P < .05). qCTD increased the number of growth predictions within ±1 mL of actual 24-hour growth by up to 47%.

CONCLUSIONS

Heterogeneous ICH attenuation on hyperacute (<3 hours) CT imaging is predictive of subsequent hematoma expansion and may reflect an active bleeding process. Further studies are required to determine whether qCTD can be incorporated into standard imaging protocols for predicting ICH growth.

European research priorities for intracerebral haemorrhage

Over 2 million people are affected by intracerebral haemorrhage (ICH) worldwide every year, one third of them dying within 1 month, and many survivors being left with permanent disability. Unlike most other stroke types, the incidence, morbidity and mortality of ICH have not declined over time. No standardised diagnostic workup for the detection of the various underlying causes of ICH currently exists, and the evidence for medical or surgical therapeutic interventions remains limited. A dedicated European research programme for ICH is needed to identify ways to reduce the burden of ICH-related death and disability. The European Research Network on Intracerebral Haemorrhage EURONICH is a multidisciplinary academic research collaboration that has been established to define current research priorities and to conduct large clinical studies on all aspects of ICH.

Radiological investigation of spontaneous intracerebral hemorrhage: systematic review and trinational survey

BACKGROUND AND PURPOSE

It is not always clear whether, how, and when to undertake further radiological investigation of spontaneous (nontraumatic) intracerebral hemorrhage (ICH).

METHODS

We systematically reviewed Ovid MEDLINE and EMBASE databases for studies of the diagnostic utility of radiological investigations of the cause(s) of ICH. We sent a structured survey to neurologists, stroke specialists, neurosurgeons, and neuroradiologists in the United Kingdom, the Netherlands, and France to assess whether, how, and when they would investigate supratentorial ICH.

RESULTS

This systematic review detected 20 relevant studies (including 1933 patients), which either quantified the yield of a radiological investigation/imaging strategy (n=15) or compared 2 imaging techniques (n=5). Six hundred ninety-two (49%) physicians responded to the survey. Further investigation would have been undertaken by the following: 99% of respondents, for younger (38 to 43 years), normotensive adults with lobar or deep ICH; 76%, for older (age 72 to 83 years), normotensive adults with deep ICH; and 31%, for older adults with deep ICH and prestroke hypertension. Younger patient age was the strongest influence on the decision to further investigate ICH (odds ratio=16; 95% confidence interval, 13 to 20), followed by the absence of prestroke hypertension (odds ratio=5; 95% confidence interval, 4 to 6) and lobar ICH location (odds ratio=2; 95% confidence interval, 1 to 2).

CONCLUSIONS

The paucity of studies on the diagnostic utility of imaging investigations of the cause(s) of ICH may contribute to the variation observed in when and how and which patients are investigated in current clinical practice. Studies comparing different types of diagnostic strategies are required.

Density and Shape as CT Predictors of Intracerebral Hemorrhage Growth

Background and Purpose— Intracerebral hemorrhage (ICH) growth predicts mortality and functional outcome. We hypothesized that irregular hematoma shape and density heterogeneity, reflecting active, multifocal bleeding or a variable bleeding time course, would predict ICH growth.

Methods— Three raters examined baseline sub-3-hour CT brain scans of 90 patients in the placebo arm of a Phase IIb trial of recombinant activated Factor VII in ICH. Each rater, blinded to growth data, independently applied novel 5-point categorical scales of density and shape to randomly presented baseline CT images of ICH. Density and shape were defined as either homogeneous/regular (Category 1 to 2) or heterogeneous/irregular (Category 3 to 5). Within- and between-rater reliability was determined for these scales. Growth was assessed as a continuous variable and using 3 binary definitions: (1) any ICH growth; (2) ≥33% or ≥12.5 mL ICH growth; and (3) radial growth >1 mm between baseline and 24-hour CT scan. Patients were divided into tertiles of baseline ICH volume: “small” (0 to 10 mL), “medium” (10 to 25 mL), and “large” (25 to 106 mL).

Results— Inter- and intrarater agreements for the novel scales exceeded 85% (±1 category). Median growth was significantly higher in the large-volume group compared with the small group ( P <0.001) and in heterogeneous compared with homogeneous ICH ( P =0.008). Median growth trended higher in irregular ICHs compared with regular ICHs ( P =0.084). Small ICHs were more regularly shaped (43%) than medium (17%) and large (3%) ICHs ( P <0.001). Small ICHs were more homogeneous (73%) compared with medium (37%) and large (17%) ICHs ( P <0.001). Adjusting for baseline ICH volume and time to scan, density heterogeneity, but not shape irregularity, independently predicted ICH growth ( P =0.046) on a continuous growth scale.

Conclusions— Large ICHs were significantly more irregular in shape, heterogeneous in density, and had greater growth. Density heterogeneity independently predicted ICH growth using some definitions.

Treatment and prevention of spontaneous intracerebral hemorrhage: comparison of EUSI and AHA/ASA recommendations

Stroke is a leading cause of death and the primary cause of permanent disability in adults in Western countries and has an enormous socioeconomic impact. Among all stroke subtypes, intracerebral hemorrhage is the deadliest form, especially in patients with intraventricular hemorrhage. In recent years, intracerebral hemorrhage has become a major focus within stroke research. The latest data from randomized controlled trials, however, have shown disappointing results. In 2006, the European Stroke Initiative published recommendations for the management of spontaneous intracerebral hemorrhage, followed by an updated recommendation by the American Heart Association/American Stroke Association in 2007. This review gives a comprehensive overview and comparison of the two recommendations. Finally, we provide an overview of ongoing clinical trials in intracerebral hemorrhage.