Endovascular treatment of acute basilar artery occlusion: Outcomes, influencing factors and imaging characteristics from the Tama-REgistry of acute thrombectomy (TREAT) study.

OBJECTIVE: The effectiveness of mechanical thrombectomy (MT) for acute basilar artery occlusion (ABAO) remains unknown. We evaluated the feasibility, safety, and efficacy of endovascular treatment for ABAO. METHODS: We retrospectively investigated patients with ABAO who underwent MT using modern stent retrievers and an aspiration device between January 2015 and March 2019 at 12 comprehensive stroke centers. Functional outcomes and 90-day mortality rates were analyzed as primary outcomes. Factors influencing outcomes were analyzed as secondary outcomes. Relationships between outcome and affected area of infarction on arrival were also analyzed. RESULTS: Seventy-three patients were included. Good outcome (modified Rankin Scale (mRS) score 0-2) was achieved in 25/73 patients (34.2%) and the all-cause 90-day mortality rate was 23.3% (17/73). Successful recanalization (modified Thrombolysis In Cerebral Infarction grade 2b and 3) was achieved in 70/73 patients (95.9%). In univariate analyses, age, National Institutes of Health Stroke Scale score, and posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) differed significantly between good and poor functional outcome groups. Age and pc-ASPECTS were significantly associated with functional outcomes in the logistic regression model. Positive findings for the midbrain on diffusion-weighted imaging on pc-ASPECTS and brainstem score were significantly associated with poor outcomes. CONCLUSION: MT with modern devices for ABAO resulted in highly successful recanalization and good outcomes. A positive finding for the midbrain on initial imaging might predict poor outcomes. Further studies are required to confirm our results.

Histogram Analysis of Diffusion-Weighted MR Imaging as a Biomarker to Predict Survival of Surgically Treated Colorectal Cancer Patients.

BACKGROUND: Structural abnormality is a well-recognized feature of malignancy. On the other hand, diffusion-weighted MRI (DWI) has been reported as a tool that can reflect tumor biology. AIMS: The purpose of this study is to apply histogram analysis to DWI to quantify structural abnormality of colorectal cancer, and evaluate its biomarker value. METHODS: This is a retrospective study of 80 (46 men and 34 women; median age: 68.0 years) colorectal cancer patients who underwent DWI followed by curative surgery at the Chiba University Hospital between 2009 and 2011. Median follow-up time was 62.2 months. Histogram parameters including signal intensity of kurtosis and skewness of the tumor were measured on DWI at b = 1000, and mean apparent diffusion coefficient value (ADC) of the tumor was also measured on ADC map generated by DWIs at b = 0 and 1000. Associations of tumor parameters (kurtosis, skewness, and ADC) with pathological features were analyzed, and these parameters were also compared with overall survival (OS) and relapse-free survival (RFS) using Cox regression and Kaplan-Meier analysis. RESULTS: ADC of the tumor did not have significant associations with any pathological factors, but kurtosis and skewness of signal intensity in the tumor was significantly different between tumors with distant metastases and those without (4.23 ± 1.31 vs. 3.24 ± 1.32, p = 0.04; 1.09 ± 0.39 vs. 0.57 ± 0.58, p = 0.03). Kurtosis of the tumor was significantly correlated with OS and RFS (p = 0.04, p = 0.03, respectively), and skewness was significantly correlated with OS (p = 0.03) in Cox regression analysis. Higher kurtosis or higher skewness of the tumor was associated with worse OS in Kaplan-Meier analysis (p = 0.01, p = 0.009, log-rank). In subset analysis, there were 50 patients (32 men and 18 women) of lymph node-negative colorectal cancers (≤ stage II); skewness of signal intensity in the tumor was associated with OS using univariate Cox regression analysis (p = 0.04). CONCLUSIONS: Histogram analysis of DWI can be a prognostic biomarker for colorectal cancer.

M2 occlusions as targets for endovascular therapy: comprehensive analysis of diffusion/perfusion MRI, angiography, and clinical outcomes.

BACKGROUND: The ideal population of patients for endovascular therapy (ET) in acute ischemic stroke remains undefined. Recent ET trials have moved towards selecting patients with proximal middle cerebral artery (MCA) or internal carotid artery occlusions, which will likely leave a gap in our understanding of the treatment outcomes of M2 occlusions. OBJECTIVE AND METHODS: To examine the presentation, treatment, and outcomes of M2 compared with M1 MCA occlusions in patients undergoing ET by assessing comprehensive MRI, angiography, and clinical data. RESULTS: We found that M2 occlusions can lead to massive strokes defined by hypoperfused and infarcted volumes as well as death or moderate to severe disability in nearly 50% of patients at discharge. Compared with M1 occlusions, M2 occlusions achieved similar Thrombolysis in Cerebral Infarction (TICI) 2b/3 recanalization rates, with significantly less hemorrhage. M2 occlusions presented with smaller infarct and hypoperfused volumes and had smaller final infarct volumes regardless of recanalization. TICI 2b/3 recanalization of M2 occlusions was associated with smaller infarct volumes compared with TICI 0-2a recanalization, as well as less infarct expansion, in patients who received IV tissue plasminogen activator as well as those that did not. Successful reperfusion of M2 occlusions was associated with improved discharge modified Rankin scale. CONCLUSIONS: If suitable as targets of ET, M2 occlusions should be given the same consideration as M1 occlusions.