[Telemedicine in stroke-pertinent to stroke care in Germany]. / Telemedizin in der Schlaganfallversorgung ­ versorgungsrelevant für Deutschland.

BACKGROUND AND OBJECTIVE: Telemedical stroke networks improve stroke care and provide access to time-dependent acute stroke treatment in predominantly rural regions. The aim is a presentation of data on its utility and regional distribution. METHODS: The working group on telemedical stroke care of the German Stroke Society performed a survey study among all telestroke networks. RESULTS: Currently, 22 telemedical stroke networks including 43 centers (per network: median 1.5, interquartile range, IQR, 1-3) as well as 225 cooperating hospitals (per network: median 9, IQR 4-17) operate in Germany and contribute to acute stroke care delivery to 48 million people. In 2018, 38,211 teleconsultations (per network: median 1340, IQR 319-2758) were performed. The thrombolysis rate was 14.1% (95% confidence interval 13.6-14.7%) and transfer for thrombectomy was initiated in 7.9% (95% confidence interval 7.5-8.4%) of ischemic stroke patients. Financial reimbursement differs regionally with compensation for telemedical stroke care in only three federal states. CONCLUSION: Telemedical stroke care is utilized in about 1 out of 10 stroke patients in Germany. Telemedical stroke networks achieve similar rates of thrombolysis and transfer for thrombectomy compared with neurological stroke units and contribute to stroke care in rural regions. Standardization of network structures, financial assurance and uniform quality measurements may further strengthen the importance of telestroke networks in the future.

Measuring changes in the optic nerve sheath diameter in patients with idiopathic normal-pressure hydrocephalus: a useful diagnostic supplement to spinal tap tests.

BACKGROUND AND PURPOSE: Cerebrospinal fluid (CSF) removal improves clinical symptoms of many patients with idiopathic normal-pressure hydrocephalus (iNPH). The aim of this study was to investigate the correlation of changes in the optic nerve sheath diameter (ONSD) with patient responses to CSF removal. METHODS: Transorbital ultrasonography was performed to obtain ONSD measurements in 31 patients with iNPH before and after lumbar puncture. Measurements were obtained while patients were supine and upright. Changes in the ONSD between supine and upright positions [ONSD variability (ONSD-V)] were assessed and compared with those in 60 healthy volunteers. ONSD-V was correlated with relative changes in a validated iNPH severity (Boon) score. RESULTS: Mean pre-puncture ONSD-V was significantly lower in healthy volunteers and patients with no response to CSF removal (Fisher test) [0.05 ± 0.14 mm (SD)] than in responsive patients [0.37 ± 0.20 mm (SD), P < 0.001]. ONSD-V predicted response to the spinal tap test (odds ratio, 0.30; 95% confidence interval, 0.12-0.75 mm, P = 0.011). The higher the ONSD-V, the better the therapeutic effect (χ2 = 14.980, P < 0.001). The post-spinal tap test ONSD-V correlated significantly with clinical severity in the motor portion of the Boon score [0.16 ± 0.23 mm (SD), P = 0.003]. CONCLUSIONS: The ONSD-V before and after spinal tap test correlated well with the clinical effects of CSF removal. Transorbital ultrasonography seems to be a reliable, safe add-on to the Fisher test and may support selection of patients for shunt intervention.

[Prolonged weaning during early neurological and neurosurgical rehabilitation : S2k guideline published by the Weaning Committee of the German Neurorehabilitation Society (DGNR)]. / Prolongiertes Weaning in der neurologisch-neurochirurgischen Frührehabilitation : S2k-Leitlinie herausgegeben von der Weaning-Kommission der Deutschen Gesellschaft für Neurorehabilitation e. V. (DGNR).

Prolonged weaning of patients with neurological or neurosurgery disorders is associated with specific characteristics, which are taken into account by the German Society for Neurorehabilitation (DGNR) in its own guideline. The current S2k guideline of the German Society for Pneumology and Respiratory Medicine is referred to explicitly with regard to definitions (e.g., weaning and weaning failure), weaning categories, pathophysiology of weaning failure, and general weaning strategies. In early neurological and neurosurgery rehabilitation, patients with central of respiratory regulation disturbances (e.g., cerebral stem lesions), swallowing disturbances (neurogenic dysphagia), neuromuscular problems (e.g., critical illness polyneuropathy, Guillain-Barre syndrome, paraplegia, Myasthenia gravis) and/or cognitive disturbances (e.g., disturbed consciousness and vigilance disorders, severe communication disorders), whose care during the weaning of ventilation requires, in addition to intensive medical competence, neurological or neurosurgical and neurorehabilitation expertise. In Germany, this competence is present in centers of early neurological and neurosurgery rehabilitation, as a hospital treatment. The guideline is based on a systematic search of guideline databases and MEDLINE. Consensus was established by means of a nominal group process and Delphi procedure moderated by the Association of the Scientific Medical Societies in Germany (AWMF). In the present guideline of the DGNR, the special structural and substantive characteristics of early neurological and neurosurgery rehabilitation and existing studies on weaning in early rehabilitation facilities are examined.Addressees of the guideline are neurologists, neurosurgeons, anesthesiologists, palliative physicians, speech therapists, intensive care staff, ergotherapists, physiotherapists, and neuropsychologists. In addition, this guideline is intended to provide information to specialists for physical medicine and rehabilitation (PMR), pneumologists, internists, respiratory therapists, the German Medical Service of Health Insurance Funds (MDK) and the German Association of Health Insurance Funds (MDS). The main goal of this guideline is to convey the current knowledge on the subject of "Prolonged weaning in early neurological and neurosurgery rehabilitation".

Ocular color-coded sonography - a promising tool for neurologists and intensive care physicians.

Ocular color-coded duplex sonography (OCCS), when performed within the safety limits of diagnostic ultrasonography, is an easy noninvasive technique with high potential for diagnosis and therapy in diseases with raised intracranial pressure and vascular diseases affecting the eye. Despite the capabilities of modern ultrasound systems and its scientific validation, OCCS has not gained widespread use in neurological practice. In this review, the authors describe the technique and main parameter settings of OCCS systems to reduce potential risks as thermal or cavitational effects for sensitive orbital structures. Applications of OCCS are the determination of intracranial pressure in emergency medicine, and follow-up evaluations of idiopathic intracranial hypertension and ventricular shunting by measuring the optic nerve sheath diameter. A diameter of 5.7 - 6.0 mm corresponds well with symptomatically increased intracranial pressure (> 20 cmH2O). OCCS also helps to discriminate between different etiologies of central retinal artery occlusion - by visualization of a "spot sign" and Doppler flow analysis of the central retinal artery - and aids the differential diagnosis of papilledema. At the end perspectives are illustrated that combine established ultrasound methods such as transcranial color-coded sonography with OCCS.

The retrobulbar "spot sign" as a discriminator between vasculitic and thrombo-embolic affections of the retinal blood supply.

PURPOSE: Sudden retinal blindness is a common complication of temporal arteritis (TA). Another common cause is embolic occlusion of the central retinal artery (CRA). The aim of this prospective study was to examine the diagnostic value of hyperechoic material in the CRA for the exclusion of vasculitis as a cause. The authors used orbital color-coded sonography (OCCS) for the detection of hyperechoic material. MATERIALS AND METHODS: 24 patients with sudden vision loss were included in the study after the exclusion of other causes (e. g. vitreous bleeding, retinal detachment). Parallel to routine diagnostic workup, OCCS was performed in all patients. RESULTS: 7 patients with a diagnosis of TA presented with different degrees of hypoperfusion in the CRA without hyperechoic material (referred to as "spot sign") detected by OCCS. Diagnostic workup in the remaining 17 patients revealed other causes of sudden vision loss, such as central retinal artery occlusion (CRAO) (12), anterior ischemic optic neuropathy (AION) (2), upstream vascular stenosis or occlusion (2) and delayed reperfusion of the CRA (1). The hyperechoic "spot sign" was visible in 10 of 12 patients (83 %) with embolic CRAO. The detection of embolic CRAO using the "spot sign" had a sensitivity of 83 % and a specificity of 100 %. The missing "spot sign" in patients with TA was a highly specific finding (p-value 0.01). CONCLUSION: The detection of the "spot sign" specifically minimizes the probability of TA as a reason for sudden blindness.

The potential of neurosonography in neurological emergency and intensive care medicine: monitoring of increased intracranial pressure, brain death diagnostics, and cerebral autoregulation­ part 2.

Transcranial B-mode sonography is an easy to use bedside imaging modality to monitor significant changes of the brain parenchyma such as in malignant middle cerebral infarction or intracerebral hemorrhage. The elevation of intracranial pressure can be followed with various neurosonographical techniques: Measurements of the ventricular width, midline shift, arterial resistance, and optic nerve sheath diameter. They should be viewed as complementary to each other and to other imaging modalities. Repeated cCT and MRI may be avoided in unstable patients by bedside neurosonography in the hands of an experienced physician. Monitoring of evolving hydrocephalus using serial measurements of the third and lateral ventricles can be used to guide therapeutic decisions such as the removal of a ventricular drainage. The cessation of cerebral blood flow in the case of intracranial pressure exceeding systemic arterial pressure is an important part of brain death diagnostics. Early demonstration of a sufficient temporal bone window is needed in patients in whom brain death may be expected. Cerebrovascular autoregulation is an integer component of the brain's blood supply and is compromised in a variety of neurological diseases. In neurological/neurosurgical patients in the intensive care unit, its assessment allows for extended neuromonitoring and control of therapeutic procedures.

[Indications and outcome of ventilated patients treated in a neurological intensive care unit]. / Indikationen und Outcome beatmeter Patienten einer neurologischen Intensivstation.

OBJECTIVE: This study characterized artificially ventilated patients in a neurological intensive care unit (NICU) between 2006-2008 in a purely neurological clinic and a so-called stand-alone situation. In addition the long-term prognoses as well as the quality of life of surviving patients were investigated. METHODS: All ventilated patients from October 2006 to December 2008 were enrolled in this descriptive, retrospective study. The duration of stay in intensive care was analyzed and the current quality of life was prospectively assessed based on the patient records. Final diagnoses, duration of intensive care unit and ventilation as well as the highest score in SAPS II (simplified acute physiology score) and complications during hospitalization were determined. The patients were divided into groups based on the diagnoses as vascular, inflammatory, neurodegenerative, hereditary, epileptogenic and others. Additionally patients were contacted and asked to respond by completing questionnaires on the Barthel index (BI) and the modified Rankin scale (mRS). RESULTS: During the study period a total of 512 patients were treated in the NICU of whom 201 required artificial respiration. Cerebrovascular diseases were the main reason for therapy in the NICU in 96 out of 201 cases (47.8%), followed by inflammatory diseases in 46 (22.8%) and epileptogenic diseases in 26 patients (13%). The median duration of artificial respiration was 9 days with a mean treatment duration of 16 days (range 1-57 days). Of the patients 31 (15.4%) died in the NICU and an additional 32 patients (18.8%) died within a median of 2 months after discharge. Outcome data were available from 67 out of 170 sent questionnaires and rehabilitation reports of 86 patients, which enabled the outcome of 121 surviving patients to be analyzed (71.2%). Of these 42.2% showed no or mild impairment in everyday life. However, the remaining 38% had severe impairments according to the BI. The evaluation of the mRS showed that 49.6% of the patients still had severe symptoms. CONCLUSIONS: More than one third of the patients treated in the NICU required artificial ventilation with an emphasis on cerebrovascular diseases, which illustrates the overlap between stroke unit and NICU care. Despite a lengthy duration of ventilation and a long stay in the intensive care unit more than one third of surviving patients showed no or only mild impairment. However, an additional third suffered from severe disability up to nursing care dependency. The study data differ little from the few publications in this field despite the stand alone situation of the NICU. The case mix index per day averaged around 0.3 and underlines the economic importance with respect to other forms of neurological treatment.

Transcranial perfusion sonography using a low mechanical index and pulse inversion harmonic imaging: reliability, inter-/intraobserver variability.

PURPOSE: Transcranial perfusion sonography (TPS) is an emerging noninvasive bedside method for evaluating brain perfusion. The purpose was to assess the feasibility of a low MI/almost real-time frame rate approach and to test its intra-/interobserver variability. MATERIALS AND METHODS: 10 healthy volunteers were investigated 3 times with TPS at a low MI (1.0) and a high frame rate (8.3 Hz). Investigations were performed by 2 sonographers in a cross-over design: 1.) twofold measurements each with 5 volunteers (intraobserver test), and 2.) single measurements of the other 5 volunteers (interobserver test). From 8 established regions of interest (ROI), time-intensity curves (TIC) with the following parameters were calculated: peak intensity (PI), time-to-PI (TTP), area-under-curve (AUC), and cerebral transit time (CTT). The TIC quality was described by the coefficient of determination. TIC parameters were presented descriptively. Intra- and interobserver variability was tested by Spearman's correlation. RESULTS: The overall quality of the TIC was very good (mean r(2) = 0.92, 0.87 - 0.97). TTP (25.7 - 28.1 sec; mean 26.8 sec) and CTT (8.2 - 10.7 sec; mean 9.9 sec) were the most robust parameters. The intraobserver variability was lower with the more experienced sonographer (r = 0.70 vs. r = 0.29). The interobserver reliability was r = 0.34 (p < 0.05). CONCLUSION: Low MI TPS allows for nearly real-time imaging facilitating probe control. Sound sonographer experience allows for a high reliability and makes TPS an interesting tool for the diagnosis and follow-up of perfusion changes, e. g. in stroke or anti-angiogenic brain tumor therapy.

Ultrasonic contrast agents in transcranial perfusion sonography (TPS) for follow-up of patients with high grade gliomas.

PURPOSE: The aim of this study was to evaluate brain perfusion differences in patients with high grade gliomas after partial tumor resection and irradiation/chemotherapy between tumor and non-tumor hemisphere by transcranial perfusion sonography (TPS) employing a contrast burst imaging (CBI) technique. METHODS: Six patients with glioblastoma (WHO Grade IV) in the temporoparietal region within the defined axial diencephalic scanning plane were examined by TPS during follow-up. All subjects had an adequate acoustic temporal bone window. Transtemporal insonation on brain tumor and non-tumor hemisphere was performed with a bolus-injection of sulphur hexafluoride-based contrast agent (10 mg i.v., 5mg/ml--SonoVue, Bracco, Altana, Switzerland). Recorded images were analysed off-line by Quanticon Software (3D-Echotech, Munich, Germany) and time intensity curve parameters [area under the curve (AUC, dB s), peak intensity (PI, dB), time to peak (TTP, s)] in five regions of interest (ROI) [thalamus anterior, thalamus posterior, nucleus lentiformis, white matter, whole hemisphere] were evaluated. Statistical analyses were performed. RESULTS: Perfusion differences between brain tumor and non-tumor hemispheres were detected with contrast burst imaging (CBI) technique with a significantly greater mean AUC (5343.69 dB s vs. 4625.04 dB s, p<0.028) and a significantly prolonged TTP (32.72 s vs. 28.91 s, p<0.046) in the tumor hemisphere. CONCLUSION: Within our study population, TTP and AUC seem to be the most robust parameters for the evaluation of cerebral perfusion differences assessed by transcranial perfusion sonography with CBI technique. We hypothesize that these results correlate with microvascular changes due to treatment regimens, such as microvessel necrosis after irradiation and chemotherapy. Above that, TPS may be of value for the long-term follow-up of brain tumor therapy concept.

DIAS I: duplex-sonographic assessment of the cerebrovascular status in acute stroke. A useful tool for future stroke trials.

BACKGROUND AND PURPOSE: A number of controlled trials have evaluated the benefit of intravenous thrombolysis in acute stroke with inconsistent results. None of these studies assessed the initial vascular status or provided information regarding the recanalization rate after therapy. Further trials need to clarify whether certain subgroups might possibly benefit more than others from intravenous thrombolysis. Therefore, a fast and valid method for assessment of cerebrovascular status is needed. In this multicenter study, we evaluated the potentials and limitations of color-coded duplex sonography (TCCS) for cerebrovascular status assessment in acute stroke patients before and after therapy. Furthermore, we compared the recanalization rate for patients referred to thrombolytic and conservative medical therapy. METHODS: Fifty-eight patients suffering from hemispheric stroke were enrolled consecutively in 8 centers. Duplex sonography was performed on admission, 2 hours after start of therapy, and 24 hours after onset of symptoms. Therapy was started within 6 hours. RESULTS: Intravenous thrombolysis was performed in 18 patients, conservative medical therapy in 39 patients, and early thromboendarterectomy in 1 patient. The middle cerebral artery (MCA) mainstem was patent in 29 patients (53.7%), occluded in 25 (46.3%), and was not assessable in 4 patients. Recanalization of the occluded MCA after 2 and 24 hours was diagnosed in 50% and 78% of the patients treated with rtPA and in 0% and 8% in the conservatively treated patients. CONCLUSIONS: Intravenous thrombolysis is highly effective in restoring blood flow after MCA occlusion. TCCS is suitable for assessment of the cerebrovascular status in acute stroke and therefore might define therapeutically relevant subgroups of patients in future stroke trials on the basis of their vascular pathology.

Noninvasive method for measuring thrombus formation in patients after peripheral angioplasty using three-dimensional B-mode and color-coded Doppler ultrasonography.

Clinical investigations studying the effect of newer medications on such complex pathophysiology as the formation of an arterial or venous mural thrombus have been limited to clinical symptomatic endpoints. Biochemical markers so far have not been convincing in quantifying ongoing thrombus formation. Consequently, clinical development of new antithrombotic compounds has had to rely on clinical symptoms that occur either comparably late in the course of the disease and may therefore be influenced by many other factors, or on those symptoms that occur at a relatively low incidence rate. Both circumstances make studies for dose-finding and determination of optimal drug regimens more difficult and time consuming. Using conventional clinical noninvasive ultrasonography, the volume and geometry of a peripheral arterial segment can be measured with high sensitivity and reproducibility in healthy volunteers (% coefficient of variation = 8.01%). In patients, thrombus volume was monitored after peripheral transluminal angioplasty of the femoral artery. All patients received a standard anticoagulant treatment with heparin for 24 hours after the procedure. Volume measurements were performed at 20, 29, 44, 53, and 68 hours after angioplasty. When compared with the obstruction volume at 20 hours, a slight increase could be detected at 29, 44, and 53 hours. At 68 hours there was a significant increase in obstruction volume. This indicates that volume measurements may detect changes in the course of thrombus formation, related to the antithrombotic treatment regimen, at a level at which clinical symptoms may not be present.

Dynamic and three-dimensional transcranial ultrasonography of an arachnoid cyst in the cerebral convexity. Technical note.

Structural imaging of the brain, such as cerebral computerized tomography (CT) and magnetic resonance (MR) imaging, is state-of-the-art. Dynamic transcranial (dTC) ultrasonography and three-dimensional (3D) transcranial color-coded duplex (TCC) ultrasonography are complementary, noninvasive procedures with the capacity for real-time imaging, which may aid in the temporary management of space-occupying lesions. A 16-year-old woman presented with recurrent tension-type headaches. A space-occupying arachnoid cyst in the cerebral convexity was demonstrated on MR images. The patient underwent an examination for raised intracranial pressure. which was performed using a standard color-coded duplex ultrasonography system attached to a personal computer-based system for 3D data acquisition. Transcranial ultrasonography was used to identify the outer arachnoid membrane of the cyst, which undulated freely in response to rotation of the patient's head (headshake maneuver). Three-dimensional data sets were acquired and, using a multiplanar reformatting reconstruction algorithm, the authors obtained high-resolution images that corresponded to the initial MR image and a follow-up cranial CT scan. No detectable differences were observed on dTC or 3D TC ultrasonograms obtained at follow-up examinations performed 9 and 28 months later. Three-dimensional TCC and dTC ultrasonography may complement conventional diagnostic procedures such as MR and CT imaging. This report represents evidence of the high resolution and good reproducibility of 3D TC methods. Ultrasonography is a mobile and inexpensive tool and may be used to improve management and therapeutic strategies for patients with space-occupying brain lesions in selected cases.

Sonographic parenchymal and brain perfusion imaging: preliminary results in four patients following decompressive surgery for malignant middle cerebral artery infarct.

To investigate new methods of diagnostic transcranial sonography for brain parenchymal, vascular and perfusion imaging, we performed 3-D native tissue harmonic transcranial sonography (3D-nthTCS), 3-D transcranial color-coded duplex sonography (3D-TCCS), and "loss-of-correlation" imaging (LOC-TCCS) in four patients following early hemicraniectomy due to space-occupying "malignant" middle cerebral artery infarction (MMCAI). Three-dimensional datasets, utilizing 3D-nthTCS and 3D-TCCS, were created and up to 10 axial 2-D B-mode image planes, similar to CCT, reconstructed in each patient. Three-dimensional reconstructions of the circle of Willis documented one persistent carotid-T occlusion and three recanalizations of the MCA. LOC-TCCS, based on stimulated acoustic emission from an ultrasound (US) contrast agent, demonstrated a perfusion deficit in 2 of 3 patients, with regard to their infarcts. Concluding, 3D-nthTCS, 3D-TCCS and LOC-TCCS are promising tools for bedside monitoring, early prognosis and treatment evaluation for MMCAI in the postoperative period. Further studies should be performed to standardize these new methods and evaluate their applications through the intact calvarina.

[Sonographic diagnostics in neurological emergency and intensive care medicine]. / Sonographische Diagnostik in der neurologischen Notfall- und Intensivmedizin.

BACKGROUND: This article gives an up-to-date overview of neurosonographic emergency and intensive care diagnostics. METHODS: Selective literature research from 1984 with critical appraisal and including national and international guidelines. RESULTS: Fast and valid diagnostics in acute stroke is the main field of application of neurosonography. Specific monitoring methods bear great advantages for intensive care patients, especially "as-often-as-wanted" repetitive imaging under real-time conditions. A number of new developments make neurosonography an interesting area of research. CONCLUSIONS: Neurosonography has played a key role in neurological emergency and intensive care medicine for many years. It remains important to continuously support dissemination of the method.