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Michael Hennerici

Publications and source records attributed to Michael Hennerici.

36 records · Page 2Linked to original sources
PubMed2005

Impact of age-related cerebral white matter changes on the transition to disability -- the LADIS study: rationale, design and methodology.

Age-related white matter changes (ARWMC) on brain MRI have been associated with cognitive, motor, mood and urinary disturbances. These factors are known to contribute to disability in elderly people, but the impact of ARWMC and of their progression on the transition to disability is not determined. The LADIS (Leukoaraiosis and Disability in the Elderly) study aims at assessing the role of ARWMC as an independent predictor of the transition to disability in initially nondisabled elderly (65-84 years). Subjects who are not impaired or impaired on only 1 item of the Instrumental Activity of Daily Living (IADL) scale, presenting with different grades of ARWMC severity, were enrolled. Eleven European centers are involved. All the patients were assessed at baseline using an extensive set of clinical and functional tests including global functioning, cognitive, motor, psychiatric and quality of life measures. MRI studies were performed at baseline and will be repeated at the end of the follow-up period to evaluate changes of ARWMC and other lesions. ARWMC were categorized into mild, moderate or severe using the scale of Fazekas et al. For each ARWMC severity class, the primary study outcome is the transition to disability defined as an impairment on 2 or more IADL scale items. Secondary outcomes are the occurrence of dementia, depression, vascular events or death. Six-hundred and thirty-nine subjects (mean age 74.13 +/- 5.0 years, M/F: 288/351) were enrolled in a hospital-based setting and are being followed up for up to 3 years. The large and comprehensive set of measures in LADIS enables a comprehensive description of their functional and clinical features to be examined in relation to different morphological patterns and severity of ARWMC. The longitudinal design will give insight into the possible role of ARWMC and their progression as an independent contributor to disability in the elderly, eventually helping to develop preventive strategies to reduce the burden of disability in late life. The study results may also help to standardize, on an international basis, tools and criteria to identify early stages of disability.

Activities of Daily Living↗
PubMed2005

Open your eyes!

Explore the source record for details and available documents.

Blepharoptosis↗
PubMed2004

From trepidant abasia to motor network failure--gait disorders as a consequence of subcortical vascular encephalopathy (SVE): review of historical and contemporary concepts.

Gait disorders in progressive subcortical vascular encephalopathy (SVE) and their impact on the burden of disability in the growing elderly population are underrepresented in medical scientific literature. The absence of a clear framework for the diagnosis and classification for gait disorders on the basis of SVE has multiple reasons: (1) neither movement disorder specialists nor stroke specialists are truly familiar with this topic and feel responsible for its treatment, (2) the existing terminology lacks a clear concept and a consistent classification, and (3) only in recent years have large prospective trials started to address the natural course of SVE. This article reviews the classical descriptions of gait disturbances with preferential view to our present concept of SVE, and comments on historical and current nosology of gait disorders aiming to propose for a new classification.

Basal Ganglia Diseases↗
PubMed2004

Transient ischemic attacks are more than "ministrokes".

BACKGROUND AND PURPOSE: Transient ischemic attacks (TIAs) are warning signs of stroke. Recently, the hypothesis was raised that TIA bears a significant risk for death and dependence and requires the same complex diagnostic workup as a complete stroke. METHODS: We prospectively collected pre- and in-hospital procedures, symptoms, outcome, complications, and therapies from a representative sample of all stroke-treating hospitals (n=82) in southwest Germany. Follow-up was attempted 6 months after discharge. End points were death or dependence in activities of daily living (Barthel Index <95, modified Rankin Scale (mRS) of 3 to 6, or institutionalization in a nursing home). RESULTS: 1380 TIA patients and 3855 stroke patients entered the database. During hospital stay, stroke incidence was 8% for TIA patients and another 5% within the first half-year. Similarly, for ischemic stroke (IS) patients these figures were 7% and 6% (P>0.05), respectively. Two percent of TIA patients died in hospital (5% afterward) compared with 9% of stroke patients (10% afterward, P<0.001). Seventeen percent TIA compared with 38% IS patients (P<0.05) were dependent at follow-up. Whereas an estimated preexisting deficit (mRS >2) was the strongest predictor for death or disability (baseline mRS odds ratio, 4.1; 95% CI, 2.3 to 7.2), admission to a stroke unit was a valid predictor for survival and independence (odds ratio, 0.4; 95% CI, 0.2 to 0.9). CONCLUSIONS: These data from a large, multicenter, nonselected, observational study underscore the "not so benign" prognosis for TIA patients. There is a relevant individual risk of early stroke, death, or disability in TIA patients. Management and treatment strategies are similar for both TIA and acute stroke.

Activities of Daily Living↗
PubMed2004

Ultrasound microbubble destruction imaging in acute middle cerebral artery stroke.

BACKGROUND AND PURPOSE: Cerebral perfusion imaging in acute stroke assists in determining the subtype and the severity of ischemia. Recent studies in perfusion models and in healthy volunteers have shown that ultrasound perfusion imaging based on microbubble destruction can be used to assess tissue perfusion. We applied ultrasound microbubble destruction imaging (MDI) to identify perfusion deficits in patients with acute middle cerebral artery (MCA) territory stroke. METHODS: Fifteen acute MCA stroke patients with sufficient transtemporal bone windows were investigated with ultrasound MDI and perfusion-weighted MRI (PWI). MDI was performed using power pulse-inversion contrast harmonic imaging. Thirty seconds after a bolus injection of the echo contrast agent SonoVue, microbubbles were destroyed using a series of high-energy pulses. Local perfusion status was analyzed in selected regions of interest by destruction curves and acoustic intensity differences (DeltaI) before and after microbubble destruction. Local perfusion status was then compared with perfusion compromise as identified on PWI. RESULTS: The mean differences of acoustic intensity from the ischemic MCA territory were significantly diminished compared with the normal hemisphere (DeltaI=2.52+/-1.75 versus DeltaI=13.79+/-7.31; P<0.001), resulting in lower slopes of microbubble destruction. PWI confirmed perfusion changes in the selected anatomical regions on time-to-peak maps in all 15 patients. CONCLUSIONS: MDI is a qualitative method that can rapidly detect perfusion changes in acute stroke. When combined with other ultrasound techniques and PWI, it may well be valuable in the care of stroke unit patients, eg, as a screening method and for follow-up assessments of perfusion deficits.

Adult↗
PubMed2004

Characterization of carotid artery plaques using real-time compound B-mode ultrasound.

BACKGROUND AND PURPOSE: Real-time compound ultrasound imaging is a new technique for improving the image quality of B-mode scanning. We investigated the value of this method for the characterization of atherosclerotic plaques in the internal carotid artery. METHODS: Thirty-two patients (22 men, 10 women; mean age, 75 years) with plaques of the internal carotid artery as identified by high-resolution B-mode scanning were investigated with real-time compound ultrasound imaging with the use of a 5- to 12-MHz dynamic range linear transducer on a duplex scanner. Two independent observers rated plaque morphology according to a standardized protocol. RESULTS: The majority of plaques was classified as predominantly echogenic and as plaques of irregular surface, whereas ulcerated plaques were rarely observed. The interobserver agreement for plaque surface characterization was good for both compound ultrasound (kappa=0.72) and conventional B-mode (kappa=0.65). For the determination of plaque echogenicity, the reproducibility of compound ultrasound (kappa(w)=0.83) was even higher than that of conventional B-mode ultrasound (kappa(w)=0.74). According to a semiquantitative analysis, real-time compound ultrasound was rated superior in the categories plaque texture resolution, plaque surface definition, and vessel wall demarcation. Furthermore, there was a significant reduction of acoustic shadowing and reverberations. CONCLUSIONS: Real-time compound ultrasound is a suitable technique for the characterization of atherosclerotic plaques, showing good general agreement with high-resolution B-mode imaging. This advanced technique allows reduction of ultrasound artifacts and improves the assessment of plaque texture and surface for enhanced evaluation of carotid plaque morphology.

Aged↗
PubMed2004

Ultrasound and arterial wall disease.

Rapid progress in non-invasive ultrasound techniques has resulted in a wide variety of clinical applications for the assessment of cerebrovascular diseases. Recent highlights in ultrasound research include the evaluation of vascular ageing as a degenerative process, the demonstration of plaque development, motion and vulnerability in atherosclerosis and multi-dimensional as well as innovative imaging techniques (e.g., compound imaging) to depict early and small vascular lesions. In addition, echo-contrast agents have been used to compensate for difficulties in visualising late, severe or subtotal obstructive plaques, but failed to be really superior to conventional techniques as evidenced in a prospective, multi-centre trial (Contrast Enhanced Duplex sonography versus Arteriography Studies - CEDAS). With increasing sophistication of ultrasound methodology, it becomes essential to establish standards for data acquisition and interpretation: three consensus meetings have provided detailed recommendations on quantification of carotid atherosclerosis, characterisation of carotid artery plaques and detection of microembolism by transcranial Doppler as a potential indicator of stroke risk.

Carotid Artery Diseases↗
PubMed2004

A rapid noninvasive method to visualize ruptured aneurysms in the emergency room: three-dimensional power Doppler imaging.

OBJECT: Three-dimensional (3D) power Doppler ultrasonography imaging provides a rapid, noninvasive visualization of ruptured intracranial aneurysms, including their relationship to other vascular structures. METHODS: The authors used transcranial 3D power Doppler imaging in the emergency room to examine patients with acute subarachnoid hemorrhage. In all patients, the ruptured aneurysm was rapidly located with 3D power Doppler imaging. Conventional x-ray angiography confirmed both the ultrasonography-based diagnosis and the location of aneurysmal bleeding. CONCLUSIONS: These preliminary results indicate that 3D power Doppler imaging is a rapid, noninvasive screening method for the visualization of ruptured aneurysms.

Adult↗
PubMed2003

Ultrasound in the treatment of ischaemic stroke.

Intravenous alteplase (recombinant tissue plasminogen activator) has been shown to be beneficial within a short 3 h window after stroke. Ultrasound has a thrombolytic capacity that can be used for pure mechanical thrombolysis or improvement of enzyme-mediated thrombolysis. Mechanical thrombolysis with ultrasound needs high intensities at the clot (>2 W/cm2) that may have unwanted side-effects, whereas improvement of enzymatic thrombolysis can be done at the safer energy levels used in diagnostic ultrasound. Methods of improving enzymatic thrombolysis with ultrasound include intra-arterial delivery of thrombolytic agents with an ultrasound-emitting catheter and targeted and non-targeted non-invasive transcranial ultra sound delivery during intravenous thrombolytic infusion. Animal and clinical studies of sonothrombolysis have shown clot lysis and accelerated recanalisation of arterial occlusion has been seen in in vitro flow models, occluded peripheral and coronary arteries, and intracerebral arteries. Controlled clinical trials to test safety management and effectiveness of both strategies are in progress.

Catheterization↗
PubMed2003

European Stroke Initiative Recommendations for Stroke Management-update 2003.

This article represents the update of 'European Stroke Initiative Recommendations for Stroke Management', first published in this Journal in 2000. The recommendations are endorsed by the 3 European societies which are represented in the European Stroke Initiative: the European Stroke Council, the European Neurological Society and the European Federation of Neurological Societies.

Emergency Medical Services↗
PubMed2003

Design and baseline characteristics of the stroke prevention by aggressive reduction in cholesterol levels (SPARCL) study.

Evidence suggests that statin therapy reduces the risk of stroke in patients with coronary heart disease (CHD), but its benefit for patients with cerebrovascular disease and no history of CHD remains uncertain. The Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) Study is a prospective, multi-centre, double-blind, randomised, placebo-controlled trial designed to evaluate the effects of atorvastatin 80 mg/day in patients who previously experienced a stroke or transient ischaemic attack, but who have no known CHD. A total of 4732 patients have been enrolled, and the data collection phase of the study is expected to be completed by October 2004. SPARCL is the first study primarily designed to prospectively evaluate the effect of statin treatment in secondary stroke prevention.

Adult↗
PubMed2002

Acceleration of cerebral blood flow velocity in a patient with sleep apnea and intracranial arterial stenosis.

Sleep apnea (SA) syndromes of different etiologies are known to induce complications including cardiovascular diseases and stroke. However, the exact mechanisms involved in cerebral ischemia remain obscure. We measured the cerebral blood flow velocities (CBFV) by means of transcranial Doppler sonography in an 81-year-old patient who presented with an acute ischemic stroke caused by an intracranial middle cerebral artery (MCA) stenosis in the presence of SA syndrome. During apnea episodes simultaneous recordings revealed reduced intra-arterial oxygen but increased carbon dioxide saturation. This resulted in an increased CBFV (220 to 320 cm/s) and suggested intermittent hemodynamic relevance of a structurally only moderate MCA stenosis. Intracranial artery stenosis can become hemodynamically significant due to episodic hypercapnia in patients with SA. This may cause ischemic infarction in the periphery of the related cerebral vascular territories.

Aged↗
PubMed2002

Inflammatory leukocyte infiltration in focal cerebral ischemia: unrelated to infarct size.

OBJECTIVE: An inflammatory host response in the ischemically injured brain is well documented. However, its pathophysiological relevance is uncertain. We investigated whether inflammatory leukocyte response in the ischemic brain alters infarct size. METHODS: The cellular inflammatory response to cerebral ischemia in Wistar-derived rats induced by the transient occlusion of the middle cerebral artery with a thread was pharmacologically upmodulated by lipopolysaccharide (LPS) or downmodulated by continuous infusion of carboxylated sialyl Lewis(x) (sLex). The effects of such experimental modulation of focal cerebral leukocyte recruitment on the extent of the resulting infarction were assessed. RESULTS: Compared to control treatments, LPS strongly enhanced (540.5 +/- 504.8 vs. 94.6 +/- 60.6, p < 0.01) and sLex decreased (32.8 +/- 29.1 vs. 97.0 +/- 49.7, p < 0.05) the numbers of neutrophils at the investigated sites in cerebral ischemia. Unexpectedly, despite such marked experimental modulation of leukocyte infiltration in the ischemic brain, the extent of the resulting cerebral infarction (percent of total hemisphere) remained unchanged under these different conditions (54.5 +/- 10.8 vs. 53.0 +/- 19.1, n.s. and 50.3 +/- 18.0 vs. 57.2 +/- 10.0, n.s., respectively). CONCLUSIONS: The striking dissociation between the massively altered inflammatory leukocyte infiltration in the ischemic brain and the unchanged infarct outcome indicates that intracerebral inflammatory leukocyte recruitment is not a major pathogenic factor in the development of ischemic tissue damage.

Animals↗
PubMed2002

Improvement in stroke quality management by an educational programme.

Time after symptom onset in ischaemic stroke has to be as short as possible to increase success of treatment. We prospectively analysed latencies from symptom onset until the start of therapy and the rate of thrombolysis in 196 patients with suspected stroke sequentially admitted to the hospital before (6 weeks prior, n = 83) and after (n = 113) initiating an educational stroke programme (EP). A total of 345 dispatchers, paramedics, and emergency staff were trained, each person for at least 2 h. The mean pre-hospital time interval from symptom onset until admission was significantly decreased by nearly 2 h (p < 0.05). Thrombolytic therapy frequencies increased from 2 to 10.5% (p < 0.01) because the overall mean time interval from admission to the start of therapy significantly decreased (p < 0.01) by 69 min after the EP, with increasing numbers of patients suitable for acute stroke therapies within a 0- to 3-hour treatment window.

Aged↗