Isolated central nervous system relapse of systemic lymphoma (SCNSL): clinical features and outcome of a retrospective analysis

We analyzed clinical outcome of patients with an isolated central nervous system lymphoma (CNSL) relapse after systemic non-Hodgkin’s lymphoma (NHL). All 23 patients with an isolated secondary CNSL (SCNSL) treated at two institutions from 04/2003–12/2007 were included into this analysis. At cerebral relapse, 15/23 patients were treated with a regimen consisting of high-dose methotrexate (Bonn protocol). After a median follow-up of 6.5 months (range 1–68), 15/23 (65%) patients with SCNSL had relapsed or progressed. HD (high-dose)- methotrexate (MTX) chemotherapy according to the Bonn protocol is effective concerning response rates; however, overall survival of patients with SCNSL seems to be impaired in comparison to relapses in primary CNSL (PCNSL)

Direct aspiration first pass technique for the treatment of acute ischemic stroke: initial experience at a European stroke center

Introduction Over the past decade, endovascular techniques for the treatment of acute ischemic stroke have emerged significantly. However, revascularization rates are limited at approximately 80%, and mechanical thrombectomy procedures still last about 1h. Therefore, we investigated the novel direct aspiration first pass technique for its efficacy and safety. Methods Our neurointerventional database was screened for patients who received mechanical thrombectomy for acute ischemic stroke using the Penumbra 5MAX ACE aspiration catheter on an intention to treat basis between November 2013 and June 2014. Procedural data, including modified Thrombolysis in Cerebral Infarction (mTICI) score, procedural timings, and complications, as well as clinical data at admission and discharge, were analyzed. Results 54 patients received mechanical thrombectomy using the 5MAX ACE. Median age was 69 (39-94) years (54% were men). Baseline National Institutes of Health Stroke Scale (NIHSS) score was 15 (2-27) and 44/54 (81%) patients received intravenous thrombolysis. Vessel occlusion sites were 91% anterior circulation and 9% posterior circulation. A successful revascularization result (mTICI 2b) was achieved in 93% of cases whereas direct aspiration alone was successful in 30/54 (56%) cases; among these, median time from groin puncture to revascularization was 30min (9-113). Symptomatic intracranial hemorrhage occurred in 2/54 (4%) patients, and embolization to new territories in 3/54 (6%). Median NIHSS at discharge was 6 (0-24); 46% of patients were independent at discharge. Conclusions The direct aspiration first pass technique proofed to be fast, effective, and safe. Promising revascularization results can be achieved quickly in more than 50% of patients using this technique as the firstline option. Nevertheless, stent retrievers are still warranted in approximately 40% of cases to achieve a favorable revascularization result

Multicenter clinical experience in over 125 patients with the Penumbra Separator 3D for mechanical thrombectomy in acute ischemic stroke

Background The aim of this study was to assess reperfusion and clinical outcome of treatment with the self-expanding retrievable Separator 3D in revascularization of acute ischemic stroke. The three-dimensional (3D) device secures thrombus with direct aspiration and supports debulking of the clot. Methods At two centers, 129 consecutive stroke patients with National Institutes of Health Stroke Scale (NIHSS) scores 5 were treated with mechanical thrombectomy using the Separator 3D as a component of the Penumbra System within 8h of symptom onset; modified Treatment in Cerebral Infarction (mTICI) revascularization scores, NIHSS score on admission and discharge, mortality rates, and modified Rankin Scale (mRS) outcomes at 90days were evaluated. Results A total of 129 vessels in 129 patients were treated. Occlusions were located in the middle cerebral artery (MCA, 48%), internal carotid artery (ICA, 33%), cervical ICA-MCA (3%), and vertebrobasilar arteries (16%). Intravenous thrombolytic therapy with recombinant tissue plasminogen activator was given to 78% of patients. Median NIHSS was 15 prior to treatment. Reperfusion to mTICI 2b or 3 was successful in 96/129 (74%) target arterial lesions, with more than half of cases (51%) achieving mTICI 3. The mean time from arterial puncture to revascularization was 65min. At 90days, the symptomatic intracranial hemorrhage rate was 4%, all cause mortality was 32%, and 43/99 patients (43%) achieved functional independence with an mRS score of 2. Conclusions The results suggest that the Separator 3D enables safe and effective revascularization of occluded large arteries in acute stroke intervention, leading to a high rate of functional independence at 90days

Complications of mechanical thrombectomy for acute ischemic stroke-a retrospective single-center study of 176 consecutive cases

There is only very limited data about complications in mechanical thrombectomy for acute ischemic stroke. The purpose of this study was to evaluate the frequency and the clinical relevance of procedure-related complications in mechanical thrombectomy. We conducted a retrospective analysis of 176 consecutive acute ischemic stroke cases that were treated with mechanical thrombectomy. Primary outcome measures included the following: symptomatic intracranial hemorrhage (sICH), vessel dissection, emboli to new vascular territories, vasospasm, and stent dislocation/occlusion whenever appropriate. Secondary outcome measures included mTICI score, time from symptom onset to revascularization, and time from groin puncture to revascularization as well as the early clinical outcome at discharge. Complications occurred in 20/176 patients (11 %) comprising 23 adverse events at the following rates: sICH 8/176 (5 %), emboli to new vascular territories 4/176 (2 %); vessel dissection 3/176 (2 %); vasospasm of the access vessel 5/176 (3 %); stent dislocation in 1/42 (2 %); and stent occlusion in 2/42 (5 %). Two out of 20 (10 %) suffered from two or more procedure-related complications. There was a statistically significant correlation of complications with time from groin puncture to revascularization, unfavorable revascularization results, and unfavorable clinical outcome. Overall, the frequency of procedure-related complications lies within acceptable limits for an emergency procedure. The endovascular treatment does not seem to add significantly to the stroke patients' risk of sICH but implies an innate risk of stroke in an initially uninvolved territory. Furthermore, a prolonged endovascular procedure beyond an hour is correlated with higher complication rates, which underlines the importance of a swift and complete revascularization

Intravenous Thrombolysis Facilitates Successful Recanalization with Stent-Retriever Mechanical Thrombectomy in Middle Cerebral Artery Occlusions

Aim: Several factors influence the outcome after acute ischemic stroke secondary to proximal occlusions of cerebral vessels. Among others, noneligibility for intravenous thrombolysis (IVT) and incomplete revascularization have been identified as predictors of unfavorable outcome. The aim of this study was to investigate whether concomitant IVT influences the revascularization efficacy in mechanical thrombectomy (MT). Methods: This study conducted a retrospective analysis of all consecutive patients presenting with an anterior circulation stroke due to large-artery occlusion with imaging evidence who were treated with MT between July 2012 and December 2013 at 2 high-volume stroke centers. Imaging data were regraded and re-evaluated according to the modified Treatment in Cerebral Ischemia scale and its respective vessel occlusion site definitions. Clinical end points included National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale; imaging and procedural measures were technical end points. Results: We identified 93 patients who presented with an occlusion of the middle cerebral artery (MCA): of these patients, 66 (71%) received IVT. We did not find statistically significant differences in the baseline NIHSS score, time from symptom onset to groin puncture, and age when comparing the IVT group with the non-IVT group. The rate of successful recanalizations (modified Treatment in Cerebral Ischemia score >= 2b) was significantly higher in patients with MCA occlusion and concomitant IVT (P = .01). Stepwise logistic regression identified IVT and thrombus length as predictive factors for successful mechanical recanalization (P = .004, P = .002). Conclusion: IVT and thrombus length are predictive factors for a successful recanalization in MT for acute ischemic stroke with underlying MCA occlusion

Diagnosis of leptomeningeal disease in diffuse large B-cell lymphomas of the central nervous system by flow cytometry and cytopathology

Reliable detection of leptomeningeal disease has the potential of facilitating the diagnosis of central nervous system (CNS) lymphoma and is important for therapeutic considerations. Currently, the standard diagnostic procedure for the detection of lymphoma in the cerebrospinal fluid is cytopathology. To improve the limited specificity and sensitivity of cytopathology, flow cytometry has been suggested as an alternative. Here, we evaluated multi-parameter flow cytometry in combination with conventional cytopathology in cerebrospinal fluid (CSF) samples from 30 patients with primary CNS lymphoma and seven patients with secondary CNS lymphoma. Overall, in 11 of 37 (29.7%) patients with CNS lymphoma, lymphoma cells were detected in CSF by flow cytometry, while cytopathology was less sensitive displaying unequivocally malignant CSF cells in only seven of all 37 (18.9%) patients. Six (16.2%) patients showed cytopathological results suspicious of lymphoma; however, in only one of these patients, the diagnosis of CSF lymphoma cells could be confirmed by flow cytometry. In primary CNS lymphomas (PCNSL), seven of 30 (23.3%) patients were positive for CSF lymphoma cells in flow cytometry, in contrast to four (13.3%) patients with PCNSL with definitely positive cytopathology. In summary, our results suggest that multi-parameter flow cytometry increases the sensitivity and specificity of leptomeningeal disease detection in CNS lymphomas. Both methods should be applied concurrently for complementary diagnostic assessment in patients with CNS lymphoma

Direct aspiration first pass technique for the treatment of acute ischemic stroke: initial experience at a European stroke center

Introduction Over the past decade, endovascular techniques for the treatment of acute ischemic stroke have emerged significantly. However, revascularization rates are limited at approximately 80%, and mechanical thrombectomy procedures still last about 1h. Therefore, we investigated the novel direct aspiration first pass technique for its efficacy and safety. Methods Our neurointerventional database was screened for patients who received mechanical thrombectomy for acute ischemic stroke using the Penumbra 5MAX ACE aspiration catheter on an intention to treat basis between November 2013 and June 2014. Procedural data, including modified Thrombolysis in Cerebral Infarction (mTICI) score, procedural timings, and complications, as well as clinical data at admission and discharge, were analyzed. Results 54 patients received mechanical thrombectomy using the 5MAX ACE. Median age was 69 (39-94) years (54% were men). Baseline National Institutes of Health Stroke Scale (NIHSS) score was 15 (2-27) and 44/54 (81%) patients received intravenous thrombolysis. Vessel occlusion sites were 91% anterior circulation and 9% posterior circulation. A successful revascularization result (mTICI 2b) was achieved in 93% of cases whereas direct aspiration alone was successful in 30/54 (56%) cases; among these, median time from groin puncture to revascularization was 30min (9-113). Symptomatic intracranial hemorrhage occurred in 2/54 (4%) patients, and embolization to new territories in 3/54 (6%). Median NIHSS at discharge was 6 (0-24); 46% of patients were independent at discharge. Conclusions The direct aspiration first pass technique proofed to be fast, effective, and safe. Promising revascularization results can be achieved quickly in more than 50% of patients using this technique as the firstline option. Nevertheless, stent retrievers are still warranted in approximately 40% of cases to achieve a favorable revascularization result

Validating EEG source imaging using intracranial electrical stimulation

Electrical source imaging is used in presurgical epilepsy evaluation and in cognitive neurosciences to localize neuronal sources of brain potentials recorded on EEG. This study evaluates the spatial accuracy of electrical source imaging for known sources, using electrical stimulation potentials recorded on simultaneous stereo-EEG and 37-electrode scalp EEG, and identifies factors determining the localization error. In 11 patients undergoing simultaneous stereo-EEG and 37-electrode scalp EEG recordings, sequential series of 99–110 biphasic pulses (2 ms pulse width) were applied by bipolar electrical stimulation on adjacent contacts of implanted stereo-EEG electrodes. The scalp EEG correlates of stimulation potentials were recorded with a sampling rate of 30 kHz. Electrical source imaging of averaged stimulation potentials was calculated utilizing a dipole source model of peak stimulation potentials based on individual four-compartment finite element method head models with various skull conductivities (range from 0.0413 to 0.001 S/m). Fitted dipoles with a goodness of fit of $\geq$80% were included in the analysis. The localization error was calculated using the Euclidean distance between the estimated dipoles and the centre point of adjacent stimulating contacts. A total of 3619 stimulation locations, respectively, dipole localizations, were included in the evaluation. Mean localization errors ranged from 10.3 to 26 mm, depending on source depth and selected skull conductivity. The mean localization error increased with an increase in source depth ($\it r$(3617) = [0.19], $\it P$ = 0.000) and decreased with an increase in skull conductivity ($\it r$(3617) = [−0.26], $\it P$ = 0.000). High skull conductivities (0.0413–0.0118 S/m) yielded significantly lower localization errors for all source depths. For superficial sources (40 mm, high skull conductivities of 0.0413 and 0.0206 S/m yielded significantly lower localization errors. In relation to stimulation locations, the majority of estimated dipoles moved outward-forward-downward to inward-forward-downward with a decrease in source depth and an increase in skull conductivity. Multivariate analysis revealed that an increase in source depth, number of skull holes and white matter volume, while a decrease in skull conductivity independently led to higher localization error. This evaluation of electrical source imaging accuracy using artificial patterns with a high signal-to-noise ratio supports its application in presurgical epilepsy evaluation and cognitive neurosciences. In our artificial potential model, optimizing the selected skull conductivity minimized the localization error. Future studies should examine if this accounts for true neural signals