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R Dziewas

Publications and source records attributed to R Dziewas.

15 recordsLinked to original sources
PubMed2006

No indication of brain reorganization after unilateral ischemic lesions of the auditory cortex.

We used magnetoencephalography to study contralesional auditory reorganization in three men with chronic unilateral ischemic lesions of the auditory cortex. Although no response was found over the lesioned hemisphere, processing in the unaffected hemisphere was indistinguishable vs healthy controls. In contrast to sensorimotor and language systems, the auditory system seems to lack contralateral reorganization, presumably because patients are typically not aware of hearing deficits and thus do not perform training.

Acoustic Stimulation↗
PubMed2005

Negative ultrasound findings in patients with cervical artery dissection. Negative ultrasound in CAD.

BACKGROUND: Cervical artery dissection (CAD) is a common cause of ischemic stroke in the younger age group. Modern imaging techniques allow the depiction of the mural hematoma, even in CADs with only subtle vessel alterations. The aim of this retrospective study was (1) to characterize the angiological features in CAD and (2) to determine the frequency of initially normal ultrasonography (US) findings. METHODS: 86 patients aged 44 +/- 11 years with CAD of the internal carotid (ICA), (n = 55) or the vertebral artery (VA), (n = 31), admitted to our hospital within 8 days (mean 1.6 days) of symptom onset, were included. CAD was confirmed either by CT-angiography, MRI of the neck, MR-angiography or digital substraction angiography (DSA) and was compared with the results of the initial as well as repeated US examinations of the arteries supplying the brain. RESULTS: In 75 patients (81.2 %) signs of vessel stenosis or occlusion were found while 11 patients (12.8%) with CAD of the ICA (n = 9) and the VA (n = 2) had normal US findings. The site of dissection in the US negative patients was highly variable without a predilection site. In 2 of 7 patients with repeated US examinations, complete vessel occlusion was found on follow-up, while in 5 patients again normal results were found. In four patients, there were changing findings in two alternative confirming imaging methods (MRI/DSA, CT/MRI) and in one patient conflicting findings (CT/MRI). Brain infarctions had occurred in 7 of the initially sonographically normal patients while the other 4 had suffered from transient (n = 2) or local (n = 2) symptoms only. CONCLUSION: Approximately 1 out of 8 patients with subsequently proven CAD has negative initial neurovascular US findings despite comprehensive examination. In patients with suspected CAD and negative US examination, repeated US examinations and further diagnostic imaging, especially MRI is necessary.

Adult↗
PubMed2005

Generalized arteriopathy in patients with cervical artery dissection.

OBJECTIVE: To make an ultrastructural comparison of superficial temporal artery (STA) biopsy specimens from patients with spontaneous cervical artery dissection (sCAD) and controls. METHODS: The authors used light microscopic examination of semithin sections and electron microscopic examination of ultrathin sections of STA biopsy specimens from patients with sCAD and controls. RESULTS: STA biopsy specimens from patients with sCAD taken around the time of the dissection showed a zone of connective tissue weakening with fissuring at the junction between the tunica media (TM) and the tunica adventitia (TA) in seven of nine specimens and erythrocyte infiltration in eight of nine specimens but in none of the control specimens. Light microscopy demonstrated transparent circular spots that, on electron microscopy, turned out to represent erythrocytes and other cellular components at different stages of degradation. Occasionally, scattered immune cells were found in specimens from patients with sCAD. In addition, smooth muscle cells of the synthetic phenotype, some of them showing extensive vacuolation were more common in the TM of STA biopsy specimens from patients with sCAD than in control specimens. CONCLUSIONS: Signs of tissue weakening along the TM/TA junction in STA biopsy specimens of patients with sCAD but not in controls suggest the presence of a generalized arteriopathy leading to impairment of the stability of the arterial wall in patients with sCAD. Limiting factors of the study are that some control biopsies were obtained from autopsies and that the anticoagulation status of patients and controls were not completely comparable.

Adult↗
PubMed2004

Protease inhibitors in spontaneous cervical artery dissections.

BACKGROUND AND PURPOSE: Observations in patients with arterial aneurysms, fibromuscular dysplasia, and spontaneous cervical artery dissection (sCAD) indicate that protease inhibitor deficiency might boost the enzymatic destruction of arterial tissue and increase the risk of these arterial wall diseases. Here we present the first large investigation of the protease inhibitor hypothesis in patients with sCAD. METHODS: Eighty patients with sCAD were compared with 80 age- and sex-matched healthy individuals. Alpha1-antitrypsin (alpha1-AT) and alpha2-macroglobulin (alpha2-MG) levels, and alpha1-AT genotypes were assessed and compared between groups. RESULTS: alpha1-AT and alpha2-MG levels as well as alpha1-AT genotypes did not differ significantly between patients and controls. The frequency of Z alleles in the patient group was higher than in the control group and than in other cohorts from Europe; however, the difference remained nonsignificant. All patients with Z alleles had internal carotid artery dissections. CONCLUSIONS: Overall, this data does not support the hypothesis that protease inhibitor levels or alpha1-AT genotypes play an important role in the etiology of sCAD. The present data does not exclude that the Pi-Z allele might have an influence on subgroups of sCAD, such as internal carotid artery dissections.

Adult↗
PubMed2004

Pneumonia in acute stroke patients fed by nasogastric tube.

BACKGROUND: Aspiration pneumonia is the most important acute complication of stroke related dysphagia. Tube feeding is usually recommended as an effective and safe way to supply nutrition in dysphagic stroke patients. OBJECTIVE: To estimate the frequency of pneumonia in acute stroke patients fed by nasogastric tube, to determine risk factors for this complication, and to examine whether the occurrence of pneumonia is related to outcome. METHODS: Over an 18 month period a prospective study was done on 100 consecutive patients with acute stroke who were given tube feeding because of dysphagia. Intermediate outcomes were pneumonia and artificial ventilation. Functional outcome was assessed at three months. Logistic regression and multivariate regression analyses were used, respectively, to identify variables significantly associated with the occurrence of pneumonia and those related to a poor outcome. RESULTS: Pneumonia was diagnosed in 44% of the tube fed patients. Most patients acquired pneumonia on the second or third day after stroke onset. Patients with pneumonia more often required endotracheal intubation and mechanical ventilation than those without pneumonia. Independent predictors for the occurrence of pneumonia were a decreased level of consciousness and severe facial palsy. The NIH stroke scale score on admission was the only independent predictor of a poor outcome. CONCLUSIONS: Nasogastric tubes offer only limited protection against aspiration pneumonia in patients with dysphagia from acute stroke. Pneumonia occurs mainly in the first days of the illness and patients with decreased consciousness and a severe facial palsy are especially endangered.

Aged↗
PubMed2003

[The megadolichobasilar artery--a clinical chameleon].

The megadolichobasilar artery is a rare vascular disease, which usually becomes apparent either due to cerebral ischemia or due to compression of the brainstem or the cranial nerves, thereby leading to a large variety of neurological symptoms. We report on a patient who suffered a sudden right-sided deafness accompanied by vertigo and vomiting. Initially, an idiopathic sensorineural hearing loss was diagnosed and later on, after no improvement took place in spite of conservative therapy, a rupture of the round window membrane was suspected. Two weeks after the first symptoms had occurred the patient developed a hemiparesis on the left side.Radiology disclosed a dilated and partially thrombosed basilar artery as well as a paramedian pontine infarction. We therefore assumed that the patient's symptoms had been caused by thrombotic occlusion of the labyrinthine artery and several rami ad pontem. The article reviews the great variety of clinical symptoms caused by megadolichobasilar artery and discusses important therapeutic options.

Basilar Artery↗
PubMed2003

Neuroimaging evidence for cortical involvement in the preparation and in the act of swallowing.

This study employed whole head magnetoencephalography and synthetic aperture magnetometry to investigate the cortical topography of the preparation and the execution of volitional and reflexive water swallowing and of a simple tongue movement. Concerning movement execution, activation of the mid-lateral primary sensorimotor cortex was strongly lateralized to the left during volitional water swallowing, less strongly lateralized to the left during reflexive water swallowing, and not lateralized at all during tongue movement. In contrast, the preparation for both volitional water swallowing and tongue movement showed a bilateral activation of the primary sensorimotor cortex. No activation was seen prior to reflexive water swallowing. Activation of the left insula and frontal operculum was observed only during both the preparation and the execution of volitional water swallowing. These new findings suggest a left hemispheric dominance for the cortical control of swallowing in humans.

Adult↗
PubMed2003

Spontaneous internal carotid artery dissection and alpha-1-antitrypsin deficiency.

Spontaneous cervical arterial dissection is an important cause of juvenile stroke. However, etiopathology and genetic background remain poorly understood. We report on a 45-year-old-male patient with homozygous alpha-1-antitrypsin (alpha-1-AT) deficiency in whom internal carotid artery dissection occurred in the absence of any other known risk factors. The relevance of alpha-1-AT deficiency for spontaneous cervical arterial dissections is discussed.

Carotid Artery, Internal, Dissection↗
PubMed2003

Placing nasogastric tubes in stroke patients with dysphagia: efficiency and tolerability of the reflex placement.

Temporary dysphagia affects up to 50% of stroke patients in the acute stage of their illness and often necessitates tube feeding. In these patients, the placing of nasogastric tubes is often difficult or impossible. This study evaluated the efficiency and tolerability of a previously described new method for tube placing, which utilises the induction of the swallowing reflex and has therefore been called "reflex placement". In 14 of 16 patients in whom the conventional approach failed, the new method was successful. A comparison of the cardiovascular responses to both methods in another 12 patients revealed significantly smaller increases in heart rate and systolic blood pressure during application of the new method. We therefore suggest the use of reflex placement in patients who have suffered a stroke and need tube feeding due to dysphagia.

Aged↗
PubMed2001

Antibody pattern analysis in the Guillain-Barré syndrome and pathologic controls.

The Guillain-Barré Syndrome (GBS) is an acute inflammatory polyneuroradiculopathy, which is considered to be caused by autoimmune processes. A number of single antigenic structures has been suggested to be targeted by the immune system, but a conclusive etiological concept has not been evolved yet. We compared reactions of sera from GBS patients (N=28) and from both two pathological control groups, 25 Multiple sclerosis (MS) patients and 32 patients with other non-inflammatory peripheral polyneuropathies (ONP) and from sex- and age-matched healthy controls (N=30). Porcine peripheral nerve proteins were used as antigens in a Western blot procedure. The blots were analysed by densitometry, and a multivariate statistical comparison of the antibody repertoires was carried out. Antibody patterns of GBS patients differed significantly (p<0.001) from each of the control groups. Discriminant analysis indicated that the discrimination resulted from pattern differences of specific regions of the blots containing proteins with estimated molecular weights of 58-64 and 28-29 kDa. We conclude that statistical analysis of antibody patterns may be helpful both in clinical diagnosis and in further research concerning the pathogenesis of GBS.

Adult↗
PubMed2001

Simple method for placing nasogastric tubes in patients with dysphagia.

Patients who have had an acute stroke often have dysphagia and tube feeding becomes necessary. In these patients placing nasogastric tubes is often difficult, or even impossible. We describe a simple method for placing nasogastric tubes by inducing the swallowing reflex, which is independent of the patient's ability to co-operate. Among nine patients for whom the conventional methods had failed 20 placements were made, 19 of which were successful. Our approach is much less distressing for patients than conventional methods.

Aged↗
PubMed2001

Axonal polyneuropathy in obstructive sleep apnoea.

Chronic hypoxaemia in chronic obstructive pulmonary disease is a well known risk factor for polyneuropathy but the impact of intermittent hypoxaemia on peripheral nerve function has not been established so far. A case-control study was performed to evaluate the prevalence of polyneuropathy in obstructive sleep apnoea (OSA). Out of 24 patients with OSA, 17 (71%) had clinical signs of polyneuropathy versus seven (33%) out of 21 matched controls. The mean amplitude of the sural sensory nerve action potential was smaller in the OSA group than in the control group, indicating axonal nerve damage. The differences were significant and could not be attributed to other known risk factors for polyneuropathy. The severity of axonal damage in patients with OSA correlated with the percentage of the night time with an O(2) saturation below 90%. It is assumed that recurrent intermittent hypoxaemia in OSA is an independent risk factor for axonal damage of peripheral nerves.

Adult↗