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result(s) for
"Gawlitza, Matthias"
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The Cerebral Surfactant System and Its Alteration in Hydrocephalic Conditions
by
Mahr, Cynthia V.
,
Bechmann, Ingo
,
Bernhard, Matthias K.
in
Biology and Life Sciences
,
Brain
,
Breathing
2016
Pulmonary Surfactant reduces surface tension in the terminal airways thus facilitating breathing and contributes to host's innate immunity. Surfactant Proteins (SP) A, B, C and D were recently identified as inherent proteins of the CNS. Aim of the study was to investigate cerebrospinal fluid (CSF) SP levels in hydrocephalus patients compared to normal subjects.
CSF SP A-D levels were quantified using commercially available ELISA kits in 126 patients (0-84 years, mean 39 years). 60 patients without CNS pathologies served as a control group. Hydrocephalus patients were separated in aqueductal stenosis (AQS, n = 24), acute hydrocephalus without aqueductal stenosis (acute HC w/o AQS, n = 16) and idiopathic normal pressure hydrocephalus (NPH, n = 20). Furthermore, six patients with pseudotumor cerebri were investigated.
SP A-D are present under physiological conditions in human CSF. SP-A is elevated in diseases accompanied by ventricular enlargement (AQS, acute HC w/o AQS) in a significant manner (0.67, 1.21 vs 0.38 ng/ml in control, p<0.001). SP-C is also elevated in hydrocephalic conditions (AQS, acute HC w/o AQS; 0.87, 1.71 vs. 0.48 ng/ml in controls, p<0.001) and in Pseudotumor cerebri (1.26 vs. 0.48 ng/ml in controls, p<0.01). SP-B and SP-D did not show significant alterations.
The present study confirms the presence of SPs in human CSF. There are significant changes of SP-A and SP-C levels in diseases affecting brain water circulation and elevation of intracranial pressure. Cause of the alterations, underlying regulatory mechanisms, as well as diagnostic and therapeutic consequences of cerebral SP's requires further thorough investigations.
Journal Article
Diffusion-Weighted MRI Reflects Proliferative Activity in Primary CNS Lymphoma
2016
To investigate if apparent diffusion coefficient (ADC) values within primary central nervous system lymphoma correlate with cellularity and proliferative activity in corresponding histological samples.
Echo-planar diffusion-weighted magnetic resonance images obtained from 21 patients with primary central nervous system lymphoma were reviewed retrospectively. Regions of interest were drawn on ADC maps corresponding to the contrast enhancing parts of the tumors. Biopsies from all 21 patients were histologically analyzed. Nuclei count, total nuclei area and average nuclei area were measured. The proliferation index was estimated as Ki-67 positive nuclei divided by total number of nuclei. Correlations of ADC values and histopathologic parameters were determined statistically.
Ki-67 staining revealed a statistically significant correlation with ADCmin (r = -0.454, p = 0.038), ADCmean (r = -0.546, p = 0.010) and ADCmax (r = -0.515, p = 0.017). Furthermore, ADCmean correlated in a statistically significant manner with total nucleic area (r = -0.500, p = 0.021).
Low ADCmin, ADCmean and ADCmax values reflect a high proliferative activity of primary cental nervous system lymphoma. Low ADCmean values-in concordance with several previously published studies-indicate an increased cellularity within the tumor.
Journal Article
Treatment of recurrent aneurysms using the Woven EndoBridge (WEB): anatomical and clinical results
by
Soize, Sebastien
,
Januel, Anne-Christine
,
Metaxas, Georgios-Emmanouil
in
Aneurysms
,
Hemorrhagic Stroke
,
Medical imaging
2018
BackgroundThe safety and efficacy of the Woven EndoBridge (WEB) for the treatment of naïve intracranial aneurysms has been confirmed.PurposeTo analyze the safety and efficacy of the WEB in the treatment of recurrent aneurysms.MethodsAnatomical and clinical results in consecutive patients with a recurrent aneurysm, who were treated using the WEB device in two French neurointerventional centers, were evaluated.ResultsSeventeen patients with 17 aneurysms were included. Treatment was feasible in 16 patients. In seven patients (41.2%), ancillary devices were used. Permanent morbidity due to a thromboembolic complication occurred in one patient (5.9%). There was no mortality. Follow-up angiographic studies were available for 15 patients after a mean of 12.1±6.1 months. Rates of complete occlusion, neck remnant, and aneurysm remnant were 33.3%, 40.0%, and 26.7%, respectively.ConclusionsTreatment of recurrent aneurysms using the WEB device may be reasonably safe and effective.
Journal Article
In Vivo Correlation of Glucose Metabolism, Cell Density and Microcirculatory Parameters in Patients with Head and Neck Cancer: Initial Results Using Simultaneous PET/MRI
2015
To demonstrate the feasibility of simultaneous acquisition of 18F-FDG-PET, diffusion-weighted imaging (DWI) and T1-weighted dynamic contrast-enhanced MRI (T1w-DCE) in an integrated simultaneous PET/MRI in patients with head and neck squamous cell cancer (HNSCC) and to investigate possible correlations between these parameters.
17 patients that had given informed consent (15 male, 2 female) with biopsy-proven HNSCC underwent simultaneous 18F-FDG-PET/MRI including DWI and T1w-DCE. SUVmax, SUVmean, ADCmean, ADCmin and Ktrans, kep and ve were measured for each tumour and correlated using Spearman's ρ.
Significant correlations were observed between SUVmean and Ktrans (ρ = 0.43; p ≤ 0.05); SUVmean and kep (ρ = 0.44; p ≤ 0.05); Ktrans and kep (ρ = 0.53; p ≤ 0.05); and between kep and ve (ρ = -0.74; p ≤ 0.01). There was a trend towards statistical significance when correlating SUVmax and ADCmin (ρ = -0.35; p = 0.08); SUVmax and Ktrans (ρ = 0.37; p = 0.07); SUVmax and kep (ρ = 0.39; p = 0.06); and ADCmean and ve (ρ = 0.4; p = 0.06).
Simultaneous 18F-FDG-PET/MRI including DWI and T1w-DCE in patients with HNSCC is feasible and allows depiction of complex interactions between glucose metabolism, microcirculatory parameters and cellular density.
Journal Article
Outcome, efficacy and safety of endovascular thrombectomy in ischaemic stroke according to time to reperfusion: data from a multicentre registry
by
Arnold, Marcel
,
Meinel, Thomas Raphael
,
Schaafsma, Joanna
in
Cardiovascular system
,
Human health and pathology
,
Life Sciences
2019
Background and purpose:
In acute ischaemic stroke (AIS) of the anterior circulation (AC) treated with mechanical thrombectomy (MT), data point to a decline of treatment effect with increasing time from symptom onset to treatment. However, the magnitude of the decline will depend on the clinical setting and imaging selection used. The aims of this study were (1) to evaluate the clinical effect of time to reperfusion (TTR); and (2) to assess the safety and technical efficacy of MT according to strata of TTR.
Methods:
Using the retrospective multicentre BEYOND-SWIFT registry data (ClinicalTrials.gov identifier: NCT03496064), we compared safety and efficacy of MT in 1461 patients between TTR strata of 0–180 min (n = 192), 180–360 min (n = 876) and >360 min (n = 393). Clinical effect of TTR was evaluated using multivariable logistic regression analyses adjusting for pre-specified confounders [adjusted odds ratios (aOR) and 95% confidence intervals (95% CI)]. Primary outcome was good functional outcome (modified Rankin Scale: mRS 0–2) at day 90.
Results:
Every hour delay in TTR was a significant factor related to mRS 0–2 (aOR 0.933, 95% CI 0.887–0.981) with an estimated 1.5% decreased probability of good functional outcome per hour delay of reperfusion, and mRS 0–1 (aOR 0.929, 95% CI 0.877–0.985). Patients with late TTR had lower rates of successful and excellent reperfusion, higher complication rates and number of passes.
Conclusions:
TTR is an independent factor related to long-term functional outcome. With increasing TTR, interventional procedures become technically less effective. Efforts should be made to shorten TTR through optimized prehospital and in-hospital pathways.
Journal Article
FLAIR Vascular Hyperintensities Indicate Slow Poststenotic Blood Flow in ICA Stenosis
by
Apfaltrer, Paul
,
Wenz, Holger
,
Groden, Christoph
in
Blood flow
,
Carotid arteries
,
Flow velocity
2021
Purpose
Occlusion or significant stenosis of the internal carotid artery (ICA) in the cervical segment is commonly associated with a poststenotic decrease in the downstream blood flow and perfusion. Fluid attenuated inversion recovery (FLAIR) vascular hyperintensities (FVH) are a phenomenon that represents slow arterial blood flow. In this study, we investigated the frequency and extent of FVH in the distal ICA in patients with proximal ICA stenosis.
Methods
We analyzed the magnetic resonance imaging (MRI) findings in 51 patients with a total of 60 cervical ICA stenoses with special focus on the frequency and extent of FVH in the area of the petrous segment of the ICA on FLAIR images and correlated these with Doppler/duplex sonography results.
Results
In 46 (76.7%) patients with ICA stenosis, FVH could be detected in the petrous segment of the ICA: in 19 (41.3%) patients a thin hyperintense rim near the vessel wall (grade 1), in 24 (52.2%) patients a strong hyperintense rim near the vessel wall (grade 2), and in 3 (6.5%) patients a hyperintense filling of the entire lumen (grade 3) was observed. The extent of FVH in the ICA in the petrous segment showed a high negative correlation with the poststenotic flow velocity (Spearman correlation, R = –0.75,
p
< 0.001), and moderate correlation with the degree of ICA stenosis (Spearman correlation, R = 0.51,
p
< 0.001).
Conclusion
An FVH in the petrous ICA is commonly seen among patients with steno-occlusive disease in proximal ICA and could therefore be useful to recognize a proximal ICA stenosis even on FLAIR images.
Journal Article
FLAIR vascular hyperintensities and 4D MR angiograms for the estimation of collateral blood flow in anterior cerebral artery ischemia
2017
To assess FLAIR vascular hyperintensities (FVH) and dynamic (4D) angiograms derived from perfusion raw data as proposed magnetic resonance (MR) imaging markers of leptomeningeal collateral circulation in patients with ischemia in the territory of the anterior cerebral artery (ACA).
Forty patients from two tertiary care university hospitals were included. Infarct volumes and perfusion deficits were manually measured on DWI images and TTP maps, respectively. FVH and collateral flow on 4D MR angiograms were assessed and graded as previously specified.
Forty-one hemispheres were affected. Mean DWI lesion volume was 8.2 (± 13.9; range 0-76.9) ml, mean TTP lesion volume was 24.5 (± 17.2, range 0-76.7) ml. FVH were observed in 26/41 (63.4%) hemispheres. Significant correlations were detected between FVH and TTP lesion volume (ρ = 0.4; P<0.01) absolute (ρ = 0.37; P<0.05) and relative mismatch volume (ρ = 0.35; P<0.05). The modified ASITN/SIR score correlated inversely with DWI lesion volume (ρ = -0.58; P<0.01) and positively with relative mismatch (ρ = 0.29; P< 0.05). ANOVA of the ASITN/SIR score revealed significant inter-group differences for DWI (P<0.001) and TTP lesion volumes (P<0.05). No correlation was observed between FVH scores and modified ASITH/SIR scores (ρ = -0.16; P = 0.32).
FVH and flow patterns on 4D MR angiograms are markers of perfusion deficits and tissue at risk. As both methods did not show a correlation between each other, they seem to provide complimentary instead of redundant information. Previously shown evidence for the meaning of these specific MR signs in internal carotid and middle cerebral artery stroke seems to be transferrable to ischemic stroke in the ACA territory.
Journal Article
Does signal without noise and noise without signal exist?
2024
Correspondence to Dr Cindy Richter, Department of Neuroradiology, University Hospital Leipzig, Leipzig, Germany; cindy.richter@medizin.uni-leipzig.de We thank Saad and Booth for their interest in our study1 and for their comments.2 We are aware that with our study, just as they state, the precise reason for non-ischemic cerebral enhancing (NICE) lesions associated with flow diverters (FD) cannot be accurately established. Considering that the amount of requested information in our questionnaire was substantial, the response rates of 34.8% and 21.7% (8 out of 23 institutions reported on their cases, 5 out of 23 disclosed the complete information on how many procedures using which devices were performed) were already below the average of these types of surveys.4 We are currently working on an analysis of the Leipzig flow diverter series with more than 300 procedures (>100 cases with one of three device families each) performed with standardized access setups. Global overview of response rates in patient and health care professional surveys in surgery: a systematic review.
Journal Article
Flow diversion treatment of complex bifurcation aneurysms beyond the circle of Willis: a single-center series with special emphasis on covered cortical branches and perforating arteries
by
Januel, Anne-Christine
,
Tall, Philippe
,
Bonneville, Fabrice
in
Angiography, Digital Subtraction
,
Cerebral Angiography
,
Cerebral Revascularization - methods
2016
BackgroundData regarding anatomic and clinical results of flow diversion treatment in complex bifurcation aneurysms of the anterior circulation are scarce.ObjectiveTo present our results of treatment of these lesions with special emphasis on the fate of ‘jailed’ cortical branches and perforating arteries.MethodsSeventeen patients were treated with flow diverters (FDs) for 18 aneurysms of the middle cerebral artery bifurcation (n=13) and the anterior communicating artery complex (n=5). Nineteen cortical branches were covered. A single FD was used in all patients.ResultsAt latest follow-up (mean 7.9 months; range 3–36; median 4.0) 2/19 (10.5%) of the covered branches were occluded, 9/19 (47.4%) showed a decreased caliber and the remaining branches were unchanged. All branch modifications were clinically asymptomatic. Mortality and permanent morbidity were 0%. Symptomatic ischemic events in perforator territories occurred in three patients (17.6%), which were reversible in all of them within 24 h. Follow-up MRI disclosed asymptomatic lacunar defects corresponding to covered perforating artery territories in five patients (29.4%). Altogether, perforator lesions—symptomatic and asymptomatic—occurred in 7/17 patients (41.2%). 33.3% of the aneurysms were occluded at latest follow-up; decreased diameters were seen in the other 66.7%.ConclusionsFlow diversion of bifurcation aneurysms is feasible with low rates of permanent morbidity and mortality. Caliber reduction and asymptomatic occlusion of covered cortical branches seems to be common, yet ischemic complications are rather linked to perforator occlusions. Our results on aneurysm occlusion rates are preliminary and longer follow-up periods are warranted.
Journal Article
Mechanical thrombectomy for basilar artery occlusion: efficacy, outcomes, and futile recanalization in comparison with the anterior circulation
by
Meinel, Thomas Raphael
,
Schaafsma, Joanna
,
Pereira, Vitor M
in
Aged
,
Aged, 80 and over
,
angiography
2019
BackgroundPerforming mechanical thrombectomy (MT) in patients with basilar artery occlusion (BAO) is currently not evidence-based.ObjectiveTo compare patients’ outcome, relative merits of achieving recanalization, and predictors of futile recanalization (FR) between BAO and anterior circulation large vessel occlusion (ACLVO) MT.MethodsIn the multicenter BEYOND-SWIFT registry (NCT03496064), univariate and multivariate (displayed as adjusted Odds Ratios, aOR and 95% confidence intervals, 95%-CI) outcome comparisons between BAO (N=165) and ACLVO (N=1574) were performed. The primary outcome was favorable outcome at 90 days (modified Rankin Scale, mRS 0-2). Secondary outcome included mortality, symptomatic intracranial hemorrhage (sICH) and FR. The relative merits of achieving successful recanalization between ACLVO and BAO were evaluated with interaction terms.ResultsMT in BAO was more often technically effective and equally safe in regards to mortality and sICH when compared to ACLVO. When adjusting for baseline differences, there was no significant difference between BAO vs ACLVO regarding rates of favorable outcome (aOR 0.986, 95%-CI 0.553 – 1.758). However, BAO were associated with increased rates of FR (aOR 2.146, 95%-CI 1.267 – 3.633). Predictors for FR were age, stroke severity, maneuver count and intracranial stenting. No significant heterogeneity on the relative merits of achieving successful recanalization on several outcome parameters were observed when comparing BAO and ACLVO.ConclusionsIn selected patients, similar outcomes can be achieved in BAO and ACLVO patients treated with MT. Randomized controlled trials comparing patient selection and interventional strategies seem warranted to avoid FR.Trial registration number NCT03496064
Journal Article