Development of Cortical Lesion Volumes on Double Inversion Recovery MRI in Patients With Relapse-Onset Multiple Sclerosis

Background and Objective: In multiple sclerosis (MS) patients, Double Inversion Recovery (DIR) magnetic resonance imaging (MRI) can be used to detect cortical lesions (CL). While the quantity and distribution of CLs seems to be associated with patients' disease course, literature lacks frequent assessments of CL volumes (CL-V) in this context. We investigated the reliability of DIR for the longitudinal assessment of CL-V development with frequent follow-up MRIs and examined the course of CL-V progressions in relation to white-matter lesions (WML), contrast enhancing lesions (CEL) and clinical parameters in patients with Relapsing-Remitting Multiple Sclerosis (RRMS).Methods: In this post-hoc analysis, image- and clinical data of a subset of 24 subjects that were part of a phase IIa clinical trial on the “Safety, Tolerability and Mechanisms of Action of Boswellic Acids in Multiple Sclerosis (SABA)” (ClinicalTrials.gov, NCT01450124) were included. The study was divided in three phases (screening, treatment, study-end). All patients received 12 MRI follow-up-examinations (including DIR) during a 16-months period. CL-Vs were assessed for each patient on each follow-up MRI separately by two experienced neuroradiologists. Results of neurological screening tests, as well as other MRI parameters (WML number and volume and CELs) were included from the SABA investigation data.Results: Inter-rater agreement regarding CL-V assessment over time was good-to-excellent (κ = 0.89). Mean intraobserver variability was 1.1%. In all patients, a total number of 218 CLs was found. Total CL-Vs of all patients increased during the 4 months of baseline screening followed by a continuous and significant decrease from month 5 until study-end (p < 0.001, Kendall'W = 0.413). A positive association between WML volumes and CL-Vs was observed during baseline screening. Decreased CL-V were associated with lower EDSS and also with improvements of SDMT- and SCRIPPS scores.Conclusion: DIR MRI seems to be a reliable tool for the frequent assessment of CL-Vs. Overall CL-Vs decreased during the follow-up period and were associated with improvements of cognitive and disability status scores. Our results suggest the presence of short-term CL-V dynamics in RRMS patients and we presume that the laborious evaluation of lesion volumes may be worthwhile for future investigations.Clinical Trial Numbers:www.ClinicalTrials.gov, “The SABA trial”; number: NCT0145012

SRC is a signaling mediator in FLT3-ITD-but not in FLT3-TKD-positive AML

Mutations of Fms-like tyrosine kinase 3 (FLT3) are among the most frequently detected molecular abnormalities in AML patients. Internal tandem duplications (ITDs) are found in approximately 25% and point mutations within the second tyrosine kinase domain (TKD) in approximately 7% of AML patients. Patients carrying the FLT3-ITD but not the FLT3-TKD mutation have a significantly worse prognosis. Therefore, both FLT3 mutations seem to exert different biologic functions. FLT3-ITD but not FLT3-TKD has been shown to induce robust activation of the STAT5 signaling pathway. In the present study, we investigated the mechanisms leading to differential STAT5 activation and show that FLT3-ITD but not FLT3-TKD uses SRC to activate STAT5. Coimmunoprecipitation and pull-down experiments revealed an exclusive interaction between SRC but not other Src family kinases and FLT3-ITD, which is mediated by the SRC SH2 domain. We identified tyrosines 589 and 591 of FLT3-ITD to be essential for SRC binding and subsequent STAT5 activation. Using sitespecific Abs, we found that both residues were significantly more strongly phosphorylated in FLT3-ITD compared with FLT3-TKD. SRC inhibition and knockdown blocked STAT5 activation and proliferation induced by FLT3-ITD but not by FLT3-TKD. We conclude that SRC might be a therapeutic target in FLT3-ITD+ AML. (Blood. 2012;119(17):4026-4033

Mechanical thrombectomy in nonagenarians with acute ischemic stroke

Background Mechanical thrombectomy (MT) is a safe and effective therapy for ischemic stroke. Nevertheless, very elderly patients aged >= 90 years were either excluded or under-represented in previous trials. It remains uncertain whether MT is warranted for this population or whether there should be an upper age limit. Methods We retrospectively reviewed 79 patients with stroke aged >= 90 years from three neurointerventional centers who underwent MT between 2013 and 2017. Good functional outcome was defined as modified Rankin scale (mRS) = 2 b. Feasibility and safety assessments included unsuccessful recanalization attempts (TICI 0), time from groin puncture to recanalization, symptomatic intracranial hemorrhage (sICH), mortality, and intervention-related serious adverse events. Results Only occlusions within the anterior circulation were included. Median time from groin puncture to recanalization was 39 min (IQR 25-57 min). The rate of successful recanalization (TICI >= 2 b) was 69.6% (55/79). Good functional outcome (mRS <= 2) at 90 days was observed in 16% (12/75) of patients. In-hospital mortality was 29.1% (23/79) and increased significantly at 90 days (46.7%, 35/75; p<0.001). sICH occurred in 5.1% (4/79) of patients. No independent predictor for good functional outcome (mRS <= 2) at 90 days was identified through logistic regression analysis. Conclusion MT in nonagenarians leads to high mortality rates and less frequently good functional outcome compared with younger patient cohorts in previous large randomized trials. However, MT appears to be safe and beneficial for a certain number of very elderly patients and therefore should generally not be withheld from nonagenarians

The Myelin Water Fraction Serves as a Marker for Age-Related Myelin Alterations in the Cerebral White Matter – A Multiparametric MRI Aging Study

International audienc

Endovascular Treatment of Very Elderly Patients Aged >= 90 With Acute Ischemic Stroke

Background Patients aged >= 90 were excluded or under-represented in past thrombectomy trials; thus, uncertainty remains whether treatment benefits can be expected regardless of age. This study investigates outcome and safety of thrombectomy in nonagenarians to improve decision making in a real-world setting. Methods and Results All currently available data of patients aged >= 90 enrolled in the GSR-ET (German Stroke Registry-Endovascular Treatment) were combined with a smaller cohort from 3 tertiary stroke centers. Baseline characteristics, procedural (Thrombolysis in Cerebral Infarction scale) and functional outcomes (modified Rankin Scale; mRS), as well as complications (symptomatic intracranial hemorrhage, serious adverse events; SAEs) were analyzed. Good functional outcome was defined as mRS = 2b) was 75.9% (154/203). Good functional outcome (mRS = 90 should be based on a case-by-case basis with regard to initial National Institute of Health Stroke Scale and Alberta Stroke Program Early CT Score