Is infarct core growth linear? Infarct volume estimation by computed tomography perfusion imaging.

OBJECTIVES: Current guidelines for recanalization treatment are based on the time elapsed between symptom onset and treatment and visualization of existing penumbra in computed tomography perfusion (CTP) imaging. The time window for treatment options relies on linear growth of infarction although individual infarct growth rate may vary. We aimed to test how accurately the estimated follow-up infarct volume (eFIV) can be approximated by using a linear growth model based on CTP baseline imaging. If eFIV did not fall within the margins of +/- 19% of the follow-up infarct volume (FIV) measured at 24 h from non-enhanced computed tomography images, the results would imply that the infarct growth is not linear. MATERIALS AND METHODS: All consecutive endovascularly treated (EVT) patients from 11/2015 to 9/2019 at the Helsinki University Hospital with large vessel occlusion (LVO), CTP imaging, and known time of symptom onset were included. Infarct growth rate was assumed to be linear and calculated by dividing the ischemic core volume (CTPcore ) by the time from symptom onset to baseline imaging. eFIV was calculated by multiplying the infarct growth rate with the time from baseline imaging to recanalization or in case of futile recanalization to follow-up imaging at 24 h, limited to the penumbra. Collateral flow was estimated by calculating hypoperfusion intensity ratio (HIR). RESULTS: Of 5234 patients, 48 had LVO, EVT, CTP imaging, and known time of symptom onset. In 40/48 patients (87%), infarct growth was not linear. HIR did not differ between patients with linear and nonlinear growth (p > .05). As expected, in over half of the patients with successful recanalization eFIV exceeded FIV. CONCLUSIONS: Infarct growth was not linear in most patients and thus time elapsed from symptom onset and CTPcore appear to be insufficient parameters for clinical decision-making in EVT candidates.

Deep brain stimulation of subthalamic nucleus modulates cortical auditory processing in advanced Parkinson's Disease.

Deep brain stimulation (DBS) has proven its clinical efficacy in Parkinson's disease (PD), but its exact mechanisms and cortical effects continue to be unclear. Subthalamic (STN) DBS acutely modifies auditory evoked responses, but its long-term effect on auditory cortical processing remains ambiguous. We studied with magnetoencephalography the effect of long-term STN DBS on auditory processing in patients with advanced PD. DBS resulted in significantly increased contra-ipsilateral auditory response latency difference at ~100 ms after stimulus onset compared with preoperative state. The effect is likely due to normalization of neuronal asynchrony in the auditory pathways. The present results indicate that STN DBS in advanced PD patients has long-lasting effects on cortical areas outside those confined to motor processing. Whole-head magnetoencephalography provides a feasible tool to study motor and non-motor neural networks in PD, and to track possible changes related to cortical reorganization or plasticity induced by DBS.

Recanalization treatment for acute ischemic stroke: 3-month outcome before and after implementation of routine endovascular treatment.

Background and purpose: Endovascular treatment for acute ischemic stroke has become a recommended treatment option for selected patients after several randomized controlled trials have shown the effectiveness of endovascular treatment. Due to the nature of randomized clinical trials, the generalizability to population based real life settings and the resulting benefits remain difficult to estimate. Methods: We included 896 consecutive patients treated with intravenous thrombolysis (IVT) within 4.5 h of stroke onset between January 2016 and December 2018, who were treated with additional endovascular treatment according to the new evidence when indicated (new-IVT-cohort). This cohort was compared to 913 intravenous thrombolysis patients treated in the 4.5 h time-window between January 2011 and December 2013 before the era of endovascular treatment (old-IVT-cohort). Results: In the new-IVT-cohort there were 253 intravenous thrombolysis + endovascular treatment treated patients. The new-IVT-cohort was associated with a better outcome on the modified Rankin Scale at 3 months in univariable ordinal regression (OR 1.27; 95% CI 1.08-1.49). The association remained significant (OR 1.65; 95% CI 1.27-2.14) also after adjustment for following confounding factors: sex, NIHSS, diabetes, atrial fibrillation, hypertension, coronary artery disease, hypercholesterolemia, myocardial infarction, heart failure, history of ischemic stroke, history of TIA, and use of antithrombotic, statins, antihypertensive, anticoagulation treatment, or endovascular treatment (Fig. 1). Conclusion: We were able to verify the efficacy of endovascular treatment in a real life cohort of intravenous thrombolysis patients even when only 28% of the patients are eligible for endovascular treatment on top of intravenous thrombolysis treatment.

Thrombolysis in stroke patients with elevated inflammatory markers.

OBJECTIVE: To investigate the prognostic value of white blood cell count (WBC) on functional outcome, mortality and bleeding risk in stroke patients treated with intravenous thrombolysis (IVT). METHODS: In this prospective multicenter study from the TRISP registry, we assessed the association between WBC on admission and 3-month poor outcome (modified Rankin Scale 3-6), mortality and occurrence of symptomatic intracranial hemorrhage (sICH; ECASS-II-criteria) in IVT-treated stroke patients. WBC was used as continuous and categorical variable distinguishing leukocytosis (WBC > 10 × 109/l) and leukopenia (WBC < 4 × 109/l). We calculated unadjusted/ adjusted odds ratios with 95% confidence intervals (OR [95% CI]) with logistic regression models. In a subgroup, we analyzed the association of combined leukocytosis and elevated C-reactive protein (CRP > 10 mg/l) on outcomes. RESULTS: Of 10,813 IVT-treated patients, 2527 had leukocytosis, 112 leukopenia and 8174 normal WBC. Increasing WBC (by 1 × 109/l) predicted poor outcome (ORadjusted 1.04[1.02-1.06]) but not mortality and sICH. Leukocytosis was independently associated with poor outcome (ORadjusted 1.48[1.29-1.69]) and mortality (ORadjusted 1.60[1.35-1.89]) but not with sICH (ORadjusted 1.17[0.94-1.45]). Leukopenia did not predict any outcome. In a subgroup, combined leukocytosis and elevated CRP had the strongest association with poor outcome (ORadjusted 2.26[1.76-2.91]) and mortality (ORadjusted 2.43[1.86-3.16]) when compared to combined normal WBC and CRP. CONCLUSION: In IVT-treated patients, leukocytosis independently predicted poor functional outcome and death. Bleeding complications after IVT were not independently associated with leukocytosis.

Is the weekend effect true in acute stroke patients at tertiary stroke center?

BACKGROUND: There is contradicting evidence on the outcome of emergency patients treated during weekends versus weekdays. We studied if outcome of ischemic stroke patients receiving intravenous thrombolysis (IVT) differs according to the treatment time. METHODS: Our retrospective study included consecutive patients receiving IVT within 4.5 h of stroke onset between June 1995 and December 2018 at the Helsinki University Hospital. The patients were compared based on the treatment initiation either during weekdays (Monday to Friday) or weekend (Saturday and Sunday). The primary outcome was 3-month mortality and secondary outcomes comprised 3-month modified Rankin Scale (mRS) and incidence of symptomatic intracerebral hemorrhage (sICH). Additional analyses studied the effect of IVT treatment according to non-office hours, time of day, and season. RESULTS: Of the 3980 IVT-treated patients, 28.0% received treatment during weekends. Mortality was similar after weekend (10.0%) and weekday (10.6%) admissions in the multivariable regression analysis (OR 0.78; 95% CI 0.59-1.03). Neither 3-month mRS (OR 0.98; 95% CI 0.86-1.12), nor the occurrence of sICH (4.2% vs 4.6%; OR 0.87; 95% CI 0.60-1.26) differed between the groups. No outcome difference was observed between the office vs non-office hours or by the time of day. However, odds for worse outcome were higher during autumn (OR 1.19; 95% CI 1.04-1.35) and winter (OR 1.15; 95% CI 1.01-1.30). CONCLUSION: We did not discover any weekend effect for IVT-treated stroke patients. This confirms that with standardized procedures, an equal quality of care can be provided to patients requiring urgent treatment irrespective of time.