Acute neurological care in north-east Germany with telemedicine support (ANNOTeM): protocol of a multi-center, controlled, open-label, two-arm intervention study.

BACKGROUND: Both diagnosis and treatment of neurological emergencies require neurological expertise and are time-sensitive. The lack of fast neurological expertise in regions with underserved infrastructure poses a major barrier for state-of-the-art care of patients with acute neurological diseases and leads to disparity in provision of health care. The main purpose of ANNOTeM (acute neurological care in North East Germany with telemedicine support) is to establish effective and sustainable support structures for evidence based treatments for stroke and other neurological emergencies and to improve outcome for acute neurological diseases in these rural regions. METHODS: A "hub-and-spoke" network structure was implemented connecting three academic neurological centres ("hubs") and rural hospitals ("spokes") caring for neurological emergencies. The network structure includes (1) the establishment of a 24/7 telemedicine consultation service, (2) the implementation of standardized operating procedures (SOPs) in the network hospitals, (3) a multiprofessional training scheme, and (4) a quality management program. Data from three major health insurance companies as well as data from the quality management program are being collected and evaluated. Primary outcome is the composite of first time of receiving paid outpatient nursing care, first time of receiving care in a nursing home, or death within 90 days after hospital admission. DISCUSSION: Beyond stroke only few studies have assessed the effects of telemedically supported networks on diagnosis and outcome of neurological emergencies. ANNOTeM will provide information whether this approach leads to improved outcome. In addition, a health economic analysis will be performed. STUDY REGISTRATION: German Clinical Trials Register DRKS00013067, date of registration: November 16 th, 2017, URL: http://www.drks.de/DRKS00013068.

Inter-rater Agreement in Three Perfusion-Computed Tomography Evaluation Methods before Endovascular Therapy for Acute Ischemic Stroke.

PURPOSE: There is ongoing debate on which method of perfusion computed tomography (PCT) evaluation in ischemic stroke is the most appropriate for improved selection of patients for endovascular treatment. We sought to test different assessment methods for inter-rater reliability. METHODS: Twenty-six patients were enrolled prospectively before endovascular therapy for acute anterior circulation ischemic stroke. Three raters experienced in stroke imaging and blinded to other imaging and clinical information independently analyzed 22 technically successful PCT scans according to 3 prespecified assessment methods applied to cerebral blood flow (CBF)/cerebral blood volume (CBV) and time-to-peak (TTP) maps: (1) visual mismatch estimate (VME), (2) Alberta Stroke Program Early CT Score perfusion method (ASPECTS-PCT), and (3) quantitative perfusion ratios (qPRs): RCBF, RCBV, RTTP. Inter-rater agreement was assessed with Cohen's kappa, intraclass correlation coefficients (ICC), Bland-Altman plots, and global and descriptive statistics. RESULTS: Significant differences between raters were found with VME and ASPECTS-PCT (P < .001) but with qPRs only for CBV (P = .03). Inter-rater agreement for VME was at best moderate by kappa statistics (.51); moderate by ICC for all parametric maps of ASPECTS-PCT (.56-.62), strong for RTTP (.76), and excellent for RCBF (.92) and RCBV (.86). Pairwise comparisons revealed less scattering of individual values with qPRs and less deviation of mean differences from 0, suggesting minor systematic deviation by any 1 rater as compared with VME or ASPECTS-PCT. CONCLUSION: PCT evaluation methods used before endovascular therapy for acute anterior circulation stroke are subject to substantial inter-rater disagreement. QPRs in PCT evaluation had better inter-rater reliability than the often used VME and ASPECTS-PCT assessment.

Diffusion tensor imaging abnormalities in photosensitive juvenile myoclonic epilepsy.

BACKGROUND AND PURPOSE: Multiple structural white matter abnormalities have been described in patients with juvenile myoclonic epilepsy (JME). In the present study, the question of whether microstructural variations exist between the two subgroups of JME, with and without photoparoxysmal responses (PPR positive and negative), was addressed using diffusion tensor imaging. METHODS: A selection of 18 patients (eight PPR positive) from a tertiary epilepsy center diagnosed with JME and 27 healthy controls was studied. The following regions of interest were investigated: the ascending reticular activating system, lateral geniculate nucleus, genu of the internal capsule, ventromedial thalamus and inferior cerebellar peduncle. RESULTS: Widespread white matter microstructural abnormalities in JME and in particular in PPR positive cases were identified. PPR positive patients demonstrated increased fractional anisotropy in the ascending reticular activating system and ventromedial thalamus compared to PPR negative patients and healthy controls. Reduced fractional anisotropy of the lateral geniculate nucleus was observed in the entire JME group compared to healthy controls. CONCLUSIONS: Several microstructural variations between PPR positive and negative JME patients have been identified. Our findings highlight the pivotal role of the thalamus in the pathophysiology of primary generalized seizures and suggest that thalamo-premotor connections are both an essential part of epileptic networks and important in the pathogenesis of photosensitivity.

Comparing perfusion CT evaluation algorithms for predicting outcome after endovascular treatment in anterior circulation ischaemic stroke.

AIM: To analyse perfusion CT (PCT) evaluation algorithms for their predictive value for outcome after endovascular therapy (ET) in acute ischaemic stroke. MATERIALS AND METHODS: Twenty-six patients were prospectively enrolled to undergo endovascular therapy for moderate to severe [National Institute of Health Stroke Scale (NIHSS) score of ≥5] anterior circulation stroke ≤6 h of onset. PCT datasets were evaluated according to three algorithms: visual mismatch estimate (VME), Alberta Stroke Programme Early CT Score (ASPECTS) perfusion, and quantitative perfusion ratios (QPRs: RCBF, RCBV) of cerebral blood flow (CBF) and volume (CBV). Results were correlated with outcome measures [NIHSS score at discharge, NIHSS score change until discharge (ΔNIHSSA/D), mRS at 90 days (mRS90d)] and compared with a matched control group. RESULTS: Recanalization was achieved in 73%, median NIHSS score decreased from 14 to 5 at discharge. The treatment and control group did not differ by VME and ASPECTS perfusion, nor did VME correlate with any of the three outcome measures. ASPECTS perfusion was not predictive of any outcome measure in the ET group. RCBF and RCBV were associated with ΔNIHSSA/D in controls and, inversely, the ET group, but not with mRS90d. Receiver operating characteristic (ROC) analysis of RCBF (and RCBV) showed a positive predictive and negative predictive value of 87% (78%) and 74% (73%), respectively, for discriminating major neurological improvement (ΔNIHSSA/D <7 versus ≥7). CONCLUSIONS: Implementation of QPRs for CBF and CBV are superior to clinically used VME and ASPECTS perfusion evaluation methods for predicting early outcome after ET for anterior circulation stroke.

CT-angiographic collateralization predicts final infarct volume after intra-arterial thrombolysis for acute anterior circulation ischemic stroke.

BACKGROUND: Final infarct volume after thrombolysis for acute ischemic stroke depends on time to, and degree of reperfusion and residual blood flow, which is influenced by leptomeningeal collateralization. We evaluated the role of collateralization in the ischemic territory as a predictor of infarct size. METHODS: Twenty-five patients (17 women, 8 men, mean age: 67.6 ± 12.4 years) selected by non-contrast-enhanced CT and CT angiography (CTA) underwent intra-arterial thrombolysis (iaT) within 6 h after symptom onset (mean 4.1 ± 1.3 h) for middle cerebral and terminal internal carotid artery (MCA/ICA) stroke. CTA was evaluated for collateralization using thick-slice coronal and axial maximum-intensity projection reconstructions according to a simple score, the CTA collateralization score (CTA-cs): 0 = no collateral filling, 1 = ≤50%, 2 = >50% but <100%, and 3 = 100% collateral filling. We analyzed the association between the final infarct volume on CT 5 days after the intervention and the CTA-cs, successful reperfusion (Thrombolysis in Myocardial Infarction, TIMI, grades 2 and 3) and time to treatment in a prospective study approved by our institutional review board, with informed consent from all patients. RESULTS: Reperfusion was achieved in 72%. Asymptomatic and symptomatic parenchymal hemorrhage occurred in 2 patients (8%) each and hemorrhagic transformation in 4 (16%). CTA-cs (r = -0.63; p < 0.001) and postinterventional TIMI grade (r = -0.403; p = 0.046) were inversely associated with final infarct volume. After multiple regression analysis, CTA-cs and reperfusion remained as independent predictors of final infarct volume whereas time to treatment and initial stroke severity did not. CONCLUSION: The extent of collateralization and reperfusion are independent predictors of final infarct volume in acute MCA/ICA stroke treated with iaT. Time to treatment and stroke severity had no independent effect on final infarct volume.

Management of Intracranial Incidental Findings on Brain MRI.

The wider use of MRI for imaging of the head in both research and clinical practice has led to an increasing number of intracranial incidental findings. Most of these findings have no immediate medical consequences. Nevertheless, knowledge of common intracranial incidental findings and their clinical relevance is necessary to adequately discuss the findings with the patient. Based on the author´s experiences from a large population-based study, the most common incidental MR findings in the brain will be presented, discussing their clinical relevance and giving recommendations for management according to the current literature and guidelines. Key points: • Intracranial incidental findings are common.• The majority of these findings have no immediate medical consequences.• Knowledge of common incidental findings is necessary for appropriate management. Citation Format: • Langner S, Buelow R, Fleck S et al. Management of Intracranial Incidental Findings on Brain MRI. Fortschr Röntgenstr 2016; 188: 1123 - 1133.

[Endovascular treatment of acute ischemic stroke under conscious sedation compared to general anesthesia - safety, feasibility and clinical and radiological outcome]. / Endovaskuläre Therapie des akut ischämischen Schlaganfalls unter Analgosedierung im Vergleich zur Intubationsnarkose - Durchführbarkeit, periprozedurale Sicherheit, klinisches und radiologisches Outcome.

PURPOSE: Vessel recanalization is an important predictor of clinical outcome in the treatment of acute ischemic stroke. Endovascular therapies are used with increasing frequency. There is no general agreement on the policy of anesthesia during endovascular therapy, ranging from general anesthesia (GA) to local anesthesia at the puncture site with conscious sedation (CS) as needed. The aim of the study was to evaluate the safety and feasibility and radiological and clinical outcome of endovascular stroke therapy under CS. MATERIALS AND METHODS: We retrospectively included all patients with acute ischemic stroke who were treated with endovascular therapy over a five-year period. Data was evaluated with respect to type of sedation, conversion from CS to GA, recanalization rate, infarct volume and peri- and post-procedural complications. RESULTS: There was a technical failure in 7 patients. Of the remaining 124 patients (mean age 68.8 ± 14.6 years), 65 were female (52 %). The site of occlusion was located in the anterior circulation in 94 patients (76 %) and in the posterior circulation in 30 cases (24 %). 105 patients (85 %) were treated under CS and 16 cases (13 %) primarily under GA. In 3 cases (2 %) peri-procedural conversion to GA was necessary. Primary intra-arterial thrombolysis, mechanical recanalization only, and combination therapy were performed in 60 (48 %), 27 (22 %) and 37 (30 %) patients, respectively. There were no significant differences for recanalization rate and complications between GA and CS. The mean procedure time was significantly shorter in patients treated under CS (p < 0.01). CONCLUSION: Endovascular stroke therapy with CS is feasible, can be performed safely and is faster than with GA.

[Diffusion-weighted MRI - how many B-values are necessary?]. / Diffusionsgewichtete MRT - wie viele Diffusionsfaktoren sind notwendig?

PURPOSE: Diffusion-weighted imaging (DWI) has become an important component in modern stroke imaging. This MR technique detects diffusion abnormalities, which can be quantified by computing apparent diffusion coefficient (ADC) maps. ADC values are typically calculated from a set of MR images obtained with varying degrees of diffusion weighting (b-values) using nonlinear regression. However, there is no agreement concerning the number of images needed for ADC calculation. The aim of our study was to determine how many b-values are necessary to reliably calculate ADC maps. MATERIALS AND METHODS: In 100 consecutive patients with clinical signs of acute ischemic stroke, 6 identically oriented and centered diffusion data sets with different b-values were acquired. ROI analysis was performed for DWI-positive lesions, normal-appearing gray and white matter, CSF, and background noise. ADC values for each ROI were calculated using a nonlinear regression model. Additionally, the CNR and SNR were calculated for each ROI. RESULTS: Acquisition time was 0:39 min for 2 b-values and up to 2:49 min for a sequence with 7 b-values. The mean ADC (× 10(-3) mm2/s) for ischemic lesions was 58.29, 58.47, 57.83, 57.81, 57.58 and 54.51 using 2, 3, 4, 5, 6, and 7 b-values. Ischemic lesions had significantly different mean ADC values only for high b-values (b = 2000 s/mm2). CONCLUSION: ADC values can be reliably calculated using 2 b-values. Radiologists may use the more time-efficient 2-point method for reliably estimating ADC values and detecting ischemic lesions in the daily clinical routine.

Pre- and postoperative investigations of hepatic glucose production and leucine turnover in Cushing's disease utilizing stable isotope techniques.

Impairment of glucose tolerance and muscle wasting indicating a disorder of glucose metabolism are characteristic features of Cushing's syndrome. We have examined glucose and amino acid metabolism in eleven patients with pituitary dependent Cushing's disease in comparison to nine healthy controls. Furthermore, the therapeutic effect of selective pituitary microsurgery was studied by repeated stable isotope measurements of hepatic glucose production and leucine turnover rates. Eight patients remitted after surgery and 3 had persistent disease. All patients were investigated prior to surgery and again 1 week and 3 months after the operation with (6,6-2H2)-glucose and (5,5,5-2H3)-leucine by means of a primed (4 mg/kg.min and 0.27 mg/kg.min), continuous (0.05 mg/kg.min and 0.005 mg/kg.min) infusion. In Cushing's disease, both the preoperatively elevated mean glucose production rate (2.34 +/- 0.63 mg/kg.min) and the reduced mean leucine turnover (0.213 +/- 0.025 mg/kg.min) were found to be linked with hepatic insulin resistance and an insulin-induced reduction in protein breakdown combined with a reduced protein synthesis. Mean glucose production and leucine flux both normalized after surgery in the remitting patients (2.18 +/- 0.15 mg/kg.min and 0.244 +/- 0.047 mg/kg.min 3 months after the operation). The metabolic disorders thus were reversible following successful correction of hormonal oversecretion by transsphenoidal surgery.