Non-contrast CT markers of intracerebral hematoma expansion : a reliability study

Objectives: We evaluated whether clinicians agree in the detection of non-contrast CT markers of intracerebral hemorrhage (ICH) expansion. Methods: From our local dataset, we randomly sampled 60 patients diagnosed with spontaneous ICH. Fifteen physicians and trainees (Stroke Neurology, Interventional and Diagnostic Neuroradiology) were trained to identify six density (Barras density, black hole, blend, hypodensity, fluid level, swirl) and three shape (Barras shape, island, satellite) expansion markers, using standardized definitions. Thirteen raters performed a second assessment. Inter and intra-rater agreement were measured using Gwet’s AC1, with a coefficient > 0.60 indicating substantial to almost perfect agreement. Results: Almost perfect inter-rater agreement was observed for the swirl (0.85, 95% CI: 0.78-0.90) and fluid level (0.84, 95% CI: 0.76-0.90) markers, while the hypodensity (0.67, 95% CI: 0.56-0.76) and blend (0.62, 95% CI: 0.51-0.71) markers showed substantial agreement. Inter-rater agreement was otherwise moderate, and comparable between density and shape markers. Inter-rater agreement was lower for the three markers that require the rater to identify one specific axial slice (Barras density, Barras shape, island: 0.46, 95% CI: 0.40-0.52 versus others: 0.60, 95% CI: 0.56-0.63). Inter-observer agreement did not differ when stratified for raters’ experience, hematoma location, volume or anticoagulation status. Intrarater agreement was substantial to almost perfect for all but the black hole marker. Conclusion: In a large sample of raters with different backgrounds and expertise levels, only four of nine non-contrast CT markers of ICH expansion showed substantial to almost perfect inter-rater agreement

Agreement between core laboratory and study investigators for imaging scores in a thrombectomy trial.

International audiencePURPOSE:We aimed to assess the agreement between study investigators and the core laboratory (core lab) of a thrombectomy trial for imaging scores.METHODS:The Alberta Stroke Program Early CT Score (ASPECTS), the European Collaborative Acute Stroke Study (ECASS) hemorrhagic transformation (HT) classification, and the Thrombolysis In Cerebral Infarction (TICI) scores as recorded by study investigators were compared with the core lab scores in order to assess interrater agreement, using Cohen's unweighted and weighted kappa statistics.RESULTS:There were frequent discrepancies between study sites and core lab for all the scores. Agreement for ASPECTS and ECASS HT classification was less than substantial, with disagreement occurring in more than one-third of cases. Agreement was higher on MRI-based scores than on CT, and was improved after dichotomization on both CT and MRI. Agreement for TICI scores was moderate (with disagreement occurring in more than 25% of patients), and went above the substantial level (less than 10% disagreement) after dichotomization (TICI 0/1/2a vs 2b/3).CONCLUSION:Discrepancies between scores assessed by the imaging core lab and those reported by study sites occurred in a significant proportion of patients. Disagreement in the assessment of ASPECTS and day 1 HT scores was more frequent on CT than on MRI. The agreement for the dichotomized TICI score (the trial's primary outcome) was substantial, with less than 10% of disagreement between study sites and core lab

The Treatment of Brain Arteriovenous Malformation Study (TOBAS): A preliminary inter- and intra-rater agreement study on patient management

International audienc

Impact of Number of Passes Before Rescue Therapy in Thrombectomy for Basilar Artery Strokes

Background When standard endovascular thrombectomy techniques fail to achieve a successful recanalization, it is often necessary to use rescue therapies (RTs). RTs are more commonly used in basilar artery occlusions and conventionally thought to represent “a last resort option.” We sought to study the outcomes of basilar artery occlusion patients who received RT, and further hypothesize that the number of instrumental passes before initiation of RT may be associated with increased risk for poor clinical outcomes. Methods We performed a retrospective analysis of the ETIS (“Endovascular Treatment in Ischemic Stroke”) registry. Our primary analysis included 277 patients who underwent thrombectomy for basilar artery occlusion, of whom 74 patients (26.7%) who received RT, defined as the use of intra‐arterial drugs, angioplasty, or stenting. Primary outcome measures included successful or complete reperfusion (final modified thrombolysis in cerebral infarction ≥2b or 3), functional independence (modified Rankin scale of 0–2), and mortality at 3 months. Results RT patients were more likely to have an atherosclerotic cause than non‐RT patients (46/74 [62.2%] versus 38/203 [18.7%]), were more likely to die (42/74 [56.8%] versus 73/203 [36.0%]), and were less likely to achieve functional independence (12/74 [16.2%] versus 84/203 [41.4%]). In the RT cohort, 17 of 74 patients (23.0%) had 1 pass before RT initiation, and 8 of 17 (47.1%) achieved a modified Rankin scale score of 0 to 2 at 3 months, with a mortality rate of 23.5% (4/17). The chance of achieving good clinical outcome decreased with each additional pass, whereas mortality increased. The odds of mortality at 3 months were highest in the >3 passes group, with an odds ratio of 10.29 (95% CI, 2.42–43.81) compared with 1 pass. None of the 25 patients with >3 passes before RT achieved 3‐month functional independence. Conclusions There is a significant correlation between the number of passes before initiation of RT and 3‐month clinical outcomes in basilar artery occlusion patients

Visual assessment of diffusion weighted imaging infarct volume lacks accuracy and reliability

International audiencePurpose The DAWN trial (Diffusion weighted imaging or CT perfusion Assessment with clinical mismatch in the triage of Wake-up and late presenting strokes undergoing Neurointervention with Trevo) has demonstrated the benefits of thrombectomy in patients with unknown or late onset strokes, using automated software (RAPID) for measurement of infarct volume. Because RAPID is not available in all centers, we aimed to assess the accuracy and repeatability of visual infarct volume estimation by clinicians and the consequences for thrombectomy decisions based on the DAWN criteria. Materials and methods 18 physicians, who routinely depend on MRI for acute stroke imaging, assessed 32 MR scans selected from a prospective databaseover two independent sessions. Raters were asked to visually estimate the diffusion weighted imaging (DWI) infarct volume for each case. Sensitivity, specificity, and accuracy of the estimated volumes were compared with the available RAPID measurements for various volume cut-off points. Thrombectomy decisions based on DAWN criteria with RAPID measurements and raters’ visual estimates were compared. Inter-rater and intra-rater agreement was measured using kappa statistics. Results The mean accuracy of raters was <90% for all volume cut-points. Inter-rater agreement was below substantial for each DWI infarct volume cut-off points. Intra-rater agreement was substantial for 55–83% of raters, depending on the selected cut-off points. Applying DAWN criteria with visual estimates instead of RAPID measurements led to 19% erroneous thrombectomy decisions, and showed a lack of reproducibility. Conclusion The visual assessment of DWI infarct volume lacks accuracy and repeatability, and could lead to a significant number of erroneous decisions when applying the DAWN criteria