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B Neundörfer

Publications and source records attributed to B Neundörfer.

At least 19 recordsLinked to original sources
PubMed2004

Laser scanning tomography of the optic nerve vs CSF opening pressure in idiopathic intracranial hypertension.

The authors investigated 17 patients with idiopathic intracranial hypertension (IIH), correlating laser scanning tomography of the optic nerve with CSF opening pressure. The decrease in papilla volume and papilla height showed a linear correlation with the opening pressure of the CSF (r = 0.59, p < 0.001; r = 0.63, p < 0.001). If the CSF opening pressure is higher than 20 cm water, an increase of 5 cm water CSF pressure corresponds to a papilla volume increase of 0.95 mm3 as well as a papilla height increase of 0.34 mm.

Adult↗
PubMed2004

[Hospitalization of non-stroke patients in a Stroke Unit].

BACKGROUND AND OBJECTIVE: Stroke care in Germany has substantially improved during the last decade. One column of modern stroke care is the institution of stroke unit which allows rapid diagnosis and treatment. The aspect of admission of nonstroke patients to a stroke unit is poorly evaluated. The aim of this study is to evaluate the number of patients who are admitted to a national stroke unit but do not suffer from stroke. Furthermore, we related the proportion of nonstroke referrals to the different referral modes. PATIENT AND METHODS: Observational study recording all suspected stroke referrals with regard to final diagnosis and type of referral during a 12-month period (1.8.2002-31.7.2003). RESULTS: 462 patients were admitted by 4 routes: 74 by paramedics or by self-presentation, 138 by emergency physicians, 144 by primary care doctors, and 106 were transferred from other hospitals. 88 patients (19 %) finally revealed no acute stroke. The most common nonstroke diagnoses were seizure (20 %), dissociative disorders (14 %), cranial nerve disorders (11 %), hypoglycaemia (8 %) and transient global amnesia (7 %). There was no significant difference among the proportion of nonstroke patients referred by ambulance paramedics and self-presentation (15 %), emergency physicians (21 %), primary care doctors (15 %) and interhospital transfer (24 %) [p = 0.222, X (2)-test according to Pearson]. CONCLUSION: Due to the fact that a number of clinical neurological conditions mimic acute stroke, misdiagnosis of stroke is common. We advocate that all stroke patients are seen early in the course of the disease by a neurologist. An alternative could be that in stroke units of internal medicine hospitals patients are seen by a consulting neurologist. Alternatively, telemedicine might be used and the neurologist on duty of a neurological stroke unit could be consulted.

Adolescent↗
PubMed2004

[Thrombus attached to a Sideris septal occluder system 6 years later].

HISTORY AND CLINICAL FINDINGS: A 61-year-old man was admitted to hospital because of right-sided hypaesthesia. Additionally he reported a brief speech disturbance some weeks before. Neurological examination indicated right-sided sensomotoric hemiparesis and left-sided upper quadrant anopia. 6 years ago recurrent transient ischaemic attacks (TIA) was diagnosed caused by paradoxical embolism through a persistent foramen ovale (PFO). The PFO was closed with a 45 mm Sideris button occluder device. After this, he reported no symptoms of cerebral ischaemia and he did not take any antiplatelet therapy. INVESTIGATIONS: Transesophageal echocardiography (TEE) showed a left atrial thrombus attached to the occluder. Cerebral computed tomography revealed infarction in regions supplied by the right posterior cerebral artery and left media cerebral artery. As additional risk factor for thrombosis a heterozygous factor V Leiden mutation was diagnosed. DIAGNOSIS: Multiple cerebral infarctions caused by a thrombus attached to an occluder system 6 years after interventional closure of persistent foramen ovale in a patient with heterozygous factor V Leiden mutation. TREATMENT AND COURSE: The patient was anticoagulated (phenprocoumon) and the thrombus gradually dissolved. CONCLUSION: A thrombosis on a Sideris occluder device may cause cerebral infarctions even years after transcatheter closure of a PFO.

Anticoagulants↗
PubMed2004

[Primary loss of consciousness and amnesia in subarachnoid hemorrhage--a quantitative study].

Subarachnoid hemorrhages (SAH) being sudden events affecting the brain in a rather wide-spread fashion are apt to induce loss of consciousness (LOC) and amnesia. The aim of the present study was to collect data on their frequency and extent. To this end we examined 48 patients at a mean of one year post-onset. Two thirds of them reported anterograde and an additional 17% retrograde amnesia; in 40% LOC (median 6 minutes) was observed. The durations were extremely skewed towards shorter times with a median of 2.7 days for anterograde and 1.3 days for retrograde amnesia who--with a single exception--were markedly shorter than anterograde amnesia. Summing up, a significant proportion of all SAH suffered LOC and amnesia occurred in the majority of cases. SAH therefore are events which with respect to LOC and amnesia bear some resemblance with closed head injuries. Exact observation and history taking may disclose important data on their severity and possible sequelae.

Adult↗
PubMed2004

Spinocerebellar ataxia type 2 with glial cell cytoplasmic inclusions.

Glial cell cytoplasmic inclusions were identified in a case of spinocerebellar ataxia type 2. These have not been reported before. The inclusions were found in low frequency in the dentate nucleus, cerebellar white matter, pontine transverse fibres, and the inferior olivary nucleus. They were of variable size and shape and expressed ubiquitin, thus resembling glial cytoplasmic inclusions in multiple system atrophy. However, their immunohistochemical profile was different as they did not show immunoreactivity for either tau protein or alpha-synuclein. There was no evidence of expanded polyglutamine tracts in these inclusions, which also failed to label with silver stains. As in many other neurodegenerative diseases, in spinocerebellar ataxia type 2 there may be pathogenic contributions of glial cells other than the common astrogliotic response to neuronal damage.

Adolescent↗
PubMed2003

Upregulation of CD40-CD40 ligand (CD154) in patients with acute cerebral ischemia.

BACKGROUND AND PURPOSE: Inflammation and hypercoagulability contribute to the development of acute cerebral ischemia. Both can be mediated by the CD40 system. This study investigated whether the CD40 system and related mediators are upregulated in patients with transient ischemic attack (TIA) or stroke. METHODS: Seventeen patients with TIA, 60 patients with complete stroke, and 15 control subjects were investigated. CD154 and P-selectin were analyzed on platelets and CD40 on monocytes during and 3 months after acute cerebral ischemia by double-label flow cytometry. Blood concentrations of soluble CD154 and monocyte chemoattractant protein-1 (MCP-1) were evaluated. RESULTS: Our main findings are as follows: (1) patients with acute cerebral ischemia showed a significant increase of CD154 on platelets and CD40 on monocytes compared with controls; (2) plasma levels of soluble CD154 were significantly higher in these patients; (3) these patients had significantly higher numbers of prothrombotic platelet-monocyte aggregates; (4) the chemoattractant MCP-1 was significantly elevated in cerebral ischemia; and (5) at 3 months' follow-up, upregulation of CD154 still persisted in patients with previous acute cerebral ischemia. CONCLUSIONS: Patients with acute cerebral ischemia show upregulation of the CD40 system, which might contribute to the known proinflammatory, proatherogenic, and prothrombotic milieu found in these patients.

Acute Disease↗
PubMed2003

Effects of age on the cardiac and vascular limbs of the arterial baroreflex.

BACKGROUND: Healthy ageing has several effects on the autonomic control of the circulation. Several studies have shown that baroreflex-mediated vagal control of the heart deteriorates with age, but so far there is little information regarding the effect of ageing on sympathetically mediated baroreflex responses. The aim of this study was to assess the effects of ageing on baroreflex control of the heart and blood vessels. MATERIALS AND METHODS: In 40 healthy volunteers, aged 20-87 years, we applied oscillatory neck suction at 0.1 Hz to assess the sympathetic modulation of the heart and blood vessels and at 0.2 Hz to assess the effect of parasympathetic stimulation on the heart. Breathing was maintained at 0.25 Hz. Blood pressure, electrocardiographic RR intervals and respiration were recorded continuously. Spectral analysis was used to evaluate the magnitude of the low-frequency (0.03-0.14 Hz) and high-frequency (0.15-0.50 Hz) oscillations in the RR interval and blood pressure. Responses to neck suction were assessed as the change in power of the RR interval and blood pressure fluctuations at the stimulation frequency from baseline values. RESULTS: Resting low- and high-frequency powers of the RR interval decreased significantly with age (P < 0.01). However, the low-frequency power of systolic blood pressure did not correlate with age. Spontaneous baroreflex sensitivity (alpha-index) showed a significant inverse correlation with age (r = -0.46, P < 0.05). Responses of the RR interval and systolic blood pressure to 0.1 Hz neck suction stimulation were not related to age, however, the RR interval response to 0.2 Hz neck suction declined significantly with age (r = -0.61, P < 0.01). CONCLUSIONS: These results confirm an age-related decrease in cardiovagal baroreflex responses. However, sympathetically mediated baroreflex control of the blood vessels is preserved with age.

Adult↗
PubMed2003

Impaired cardiovagal and vasomotor responses to baroreceptor stimulation in type II diabetes mellitus.

BACKGROUND: In diabetic patients, impairment of the cardiovagal limb of the baroreflex has been well established. However, the role of sympathetic mediated baroreflex vasomotor control of the blood vessels is not well defined. We therefore assessed the vasomotor responses to sinusoidal baroreceptor stimulation in diabetic patients. MATERIALS AND METHODS: We studied 14 type II diabetic patients (age; 57 +/- 7 years) and 18 healthy controls (age; 59 +/- 11 years). Oscillatory neck suction was applied at 0.1 Hz to assess the sympathetic modulation of the heart and blood vessels, and at 0.2 Hz to assess the effect of parasympathetic stimulation on the heart. Breathing was paced at 0.25 Hz. Spectral analysis was used to evaluate the oscillatory responses of RR-interval and blood pressure. RESULTS: The diabetic patients showed a significantly lower RR-interval response (P < 0.05) to the 0.1 Hz neck suction (2.52 +/- 0.50-3.62 +/- 0.54 ln ms2) than the controls (4.23 +/- 0.31-6.74 +/- 0.36 ln ms2). The increase in power of 0.1 Hz systolic blood pressure oscillations during 0.1 Hz suction was also significantly smaller (P < 0.05) in the diabetics (1.17 +/- 0.44-1.69 +/- 0.44 mmHg2) than in the controls (1.60 +/- 0.29 mmHg2-5.87 +/- 1.25 mmHg2). The magnitude of the peak of the 0.2 Hz oscillation in the RR-interval in response to 0.2 Hz neck stimulation was significantly greater (P < 0.05) in the controls (3.42 +/- 0.46 ln ms2) than in the diabetics (1.58 +/- 0.44 ln ms2). CONCLUSION: In addition to cardiovagal dysfunction, baroreflex-mediated sympathetic modulation of the blood vessels is impaired in type II diabetic patients.

Aged↗
PubMed2003

Choreoathetosis related to lithium intoxication.

A 76-year old woman was admitted because of severe gait ataxia and dysarthric speech that had worsened over the last 24 h. The patient was initially suspected of having repeated transitory ischemic attacks (TIAs) as her daughter reported a similar episode that had happened 3 weeks prior to admission. The onset of spontaneous twisting, choreoathetotic movements of both hands and arms and worsening of symptoms one hour after admission together with a history of lithium therapy lead to the correct diagnosis and appropriate treatment.

Aged↗
PubMed2003

Effects of lower body negative pressure on cardiac and vascular responses to carotid baroreflex stimulation.

The aim of this study was to assess carotid baroreflex responses during graded lower body negative pressure (LBNP). In 12 healthy subjects (age 29+/-4 years) we applied sinusoidal neck suction (0 to -30 mmHg) at 0.1 Hz to examine the sympathetic modulation of the heart and blood vessels and at 0.2 Hz to assess the effect of parasympathetic stimulation on the heart. Responses to neck suction were determined as the change in spectral power of RR-interval and blood pressure from baseline values. Measurements were carried out during progressive applications (0 to -50 mmHg) of LBNP. Responses to 0.1 and 0.2 Hz carotid baroreceptor stimulations during low levels of LBNP (-10 mmHg) were not significantly different from those measured during baseline. At higher levels of LBNP, blood pressure responses to 0.1 Hz neck suction were significantly enhanced, but with no significant change in the RR-interval response. LBNP at all levels had no effect on the RR-interval response to 0.2 Hz neck suction. The unchanged responses of RR-interval and blood pressure to neck suction during low level LBNP at -10 mmHg suggest no effect of cardiopulmonary receptor unloading on the carotid arterial baroreflex, since this LBNP level is considered to stimulate cardiopulmonary but not arterial baroreflexes. Enhanced blood pressure responses to neck suction during higher levels of LBNP are not necessarily the result of a reflex interaction but may serve to protect the circulation from fluctuations in blood pressure while standing.

Adult↗
PubMed2002

Somatosensory evoked magnetic fields following passive movement compared with tactile stimulation of the index finger.

Cortical processing of passive finger movement was assessed magnetoencephalographically in 12 healthy volunteers and compared with somatosensory evoked magnetic fields (SEF) following tactile stimulation. A new device comprising a clamp-like digit holder facilitated bilateral guidance of the briskly elevated index finger. Both passive movement and tactile stimulation induced activation of the contralateral primary somatosensory (SI) cortex, indicated by six SEF deflections with inter-individually rather consistent peak latencies of 20-230 ms following proprioceptive and 20-300 ms following tactile stimulation. SEF responses to the two stimulus modalities clearly differed with regard to peak latencies, amplitudes and orientations of equivalent current dipoles (ECDs). The strength and orientation of proprioception-related ECDs suggested sequential activation of SI generators, with possible involvement of areas 3a and/or 2 at around 20 ms, area 4 at approximate peak latencies of 65 and 100 ms and area 3b between 150 to 230 ms. Passive movement elicited additional activation of cortical regions outside SI, including the bilateral perisylvian regions and the contralateral cingulate gyrus at latencies of 40-470 and 150-500 ms respectively. The study provides new results with respect to the spatiotemporal analysis of proprioception-related cortical processing and may contribute to a better understanding of the modality-specific organization of the human somatosensory cortex.

Adult↗
PubMed2002

Assessment of the neurogenic flare reaction in small-fiber neuropathies.

To improve sensitivity of the analysis of axon reflex flare reaction, the authors used a laser Doppler scanner and analyzed flare intensity and size induced by histamine iontophoresis simultaneously at the foot and thigh in patients with small-fiber neuropathy (n = 10) and controls (n = 9). Flare size, but not laser Doppler flux, clearly distinguished patients from controls at both locations (p < 0.01) and may be useful for evaluation of small-fiber neuropathies.

Aged↗