50 research outputs found
Facilitation of oral sensitivity by electrical stimulation of the faucial pillars
Dysphagia is common in neurological disease. However, our understanding of swallowing and its central nervous control is limited. Sensory information plays a vital role in the initiation of the swallowing reflex and is often reduced in stroke patients. We hypothesized that the sensitivity threshold of the anterior faucial pillar could be facilitated by either electrical stimulation (ES) or taste and smell information. The sensitivity threshold was measured by ES in the anterior faucial pillar region. The measurement was repeated 5 min after baseline. Thirty minutes after baseline, the participants underwent a test for taste and smell. Immediately after the test, the ES was repeated. Thirty healthy volunteers with a mean age of 275.1 participated in the trial. Mean sensitivity threshold at baseline was 1.9 +/- 0.59 mA. The values 5 min after baseline (1.74 +/- 0.56 mA, p=0.027) and 30 min after baseline (1.67 +/- 0.58 mA, p=0.011) were significantly lower compared to the baseline, but there was no difference between the latter (p=0.321). After 5 min, a potentially facilitating effect was found on oral sensitivity by ES of the faucial pillar area. Thirty minutes later, this effect was still present. Trial registration Clinicaltrials.gov, NCT03240965. Registered 7th August 2017-https://clinicaltrials.gov/ct2/show/NCT03240965
Isolated Dysphagia in a Patient with Medial Medullary Infarction – Effects of Evidence-Based Dysphagia Therapy: A Case Report
Medial medullary infarction (MMI) is a vascular occlusion in the medulla oblongata leading to certain constellations of neurological symptoms and seriously affecting the patient. Effective evidence-based treatment of severe dysphagia as sole symptom of MMI has not yet been reported. This case study aims to report successful effects of evidence-based therapy based on findings of dysphagia symptoms and pathophysiology of swallowing by flexible endoscopic evaluation of swallowing (FEES) in severe isolated dysphagia after MMI. FEES was performed to evaluate swallowing pathophysiology and dysphagia symptoms in a 57-year-old male with severe dysphagia after MMI. On the basis of FEES findings, simple and high-frequent evidence-based exercises for improvement of swallowing were implemented: thermal stimulation of faucial arches, Jaw Opening Exercise, and Jaw Opening Against Resistance. After 7 weeks of high-frequent evidence-based therapy and regular FEES evaluation the patient was set on full oral diet with no evidence of aspiration risk. In a first case report of isolated dysphagia in MMI our case illustrates that high-frequent evidence-based dysphagia therapy in combination with FEES as the method to evaluate and monitor swallowing pathophysiology can lead to successful and quick rehabilitation of severely affected dysphagic patients
Neuroprotective effects of MK-801 in different rat stroke models for permanent middle cerebral artery occlusion: adverse effects of hypothalamic damage and strategies for its avoidance
BACKGROUND AND PURPOSE: Permanent middle cerebral artery occlusion (MCAO) with the use of the suture technique causes hypothalamic damage with subsequent hyperthermia, which can confound neuroprotective drug studies. In the present study the neuroprotective effects of dizocilpine (MK-801) were compared in different permanent MCAO models with and without hypothalamic damage and hyperthermia.
METHODS: Sixty Sprague-Dawley rats were treated with MK-801 or placebo, beginning 15 minutes before MCAO, and assigned to the following groups: suture MCAO (group I), macrosphere MCAO without hypothalamic damage (group II), or macrosphere MCAO with intentionally induced hypothalamic infarction (group III). Body temperature was measured at 3, 6, and 24 hours. Lesion size was determined after 24 hours (2,3,5-triphenyltetrazolium chloride staining).
RESULTS: Hypothalamic damage was present in animals in group I and was intentionally induced in group III with the use of a modified macrosphere MCAO technique. Body temperature was significantly increased 3, 6, and 24 hours after MCAO in these 2 groups of animals. Hypothalamic damage and subsequent hyperthermia could be avoided effectively by limiting the number of macrospheres (group II). MK-801 provided a highly significant neuroprotective effect in group II but not in groups I and III.
CONCLUSIONS: Hypothalamic damage with subsequent hyperthermia masked the neuroprotective effect of MK-801. This side effect can be avoided by using the macrosphere MCAO technique with a limited number of spheres. This model therefore may be more appropriate to study the effects of neuroprotective drugs in permanent focal cerebral ischemia than the suture method
A rare cause of stroke: fail-implanted venous port catheter system – a case report
Background!#!We present the case of a 75-year-old female with acute embolic cerebral infarction caused by a fail-implanted venous port catheter system in the left subclavian artery.!##!Case presentation!#!A 75-year-old woman presented to our emergency room after acute onset of a right-sided hemiparesis and dysarthria. Within 2 days after admission, she developed a left-sided hemiparesis, ataxia with concordant gait disturbance and incoordination of the left upper limb. DWI-MRI showed acute multiple infarcts in both cerebral and cerebellar hemispheres. Laboratory examination, 24-h Holter electrocardiography and transthoracic echocardiography provided no pathological findings. Further examination revealed an arterially fail-implanted port catheter, placed in the left subclavian artery with its tip overlying the ascending aorta, as the source of cerebral embolism.!##!Conclusion!#!This is the first case report of thromboembolic, cerebral infarction due to a misplaced venous port catheter in the subclavian artery, emphasizing the imperative need for a thorough diagnostic workup, when embolism is suspected but cannot be proven at first glance
The macrosphere model: evaluation of a new stroke model for permanent middle cerebral artery occlusion in rats
BACKGROUND AND PURPOSE: The suture middle cerebral artery occlusion (MCAO) model is widely used for the simulation of focal cerebral ischemia in rats. This technique causes hypothalamic injury resulting in hyperthermia, which can worsen outcome and obscure neuroprotective effects. Herein, we introduce a new MCAO model that avoids these disadvantages.
METHODS: Permanent MCAO was performed by intraarterial embolization using six TiO(2) macrospheres (0.3-0.4 mm in diameter) or by the suture occlusion technique. Body temperature was monitored, functional and histologic outcome was assessed after 24 h. Additional 16 rats were subjected to macrosphere or suture MCAO. Lesion progression was evaluated using magnetic resonance imaging (MRI).
RESULTS: The animals subjected to suture MCAO developed hyperthermia (\u3e39 degrees C), while the temperature remained normal in the macrosphere MCAO group. Infarct size, functional outcome and model failure rate were not significantly different between the groups. Lesion size on MRI increased within the first 90 min and remained unchanged thereafter in both groups.
CONCLUSIONS: The macrosphere MCAO model provides reproducible focal cerebral ischemia, similar to the established suture technique, but avoids hypothalamic damage and hyperthermia. This model, therefore, may be more appropriate for the preclinical evaluation of neuroprotective therapies and can also be used for stroke studies under difficult conditions, e.g., in awake animals or inside the MRI scanner
Evaluation of the middle cerebral artery occlusion techniques in the rat by in-vitro 3-dimensional micro- and nano computed tomography
Abstract Background Animal models of focal cerebral ischemia are widely used in stroke research. The purpose of our study was to evaluate and compare the cerebral macro- and microvascular architecture of rats in two different models of permanent middle cerebral artery occlusion using an innovative quantitative micro- and nano-CT imaging technique. Methods 4h of middle cerebral artery occlusion was performed in rats using the macrosphere method or the suture technique. After contrast perfusion, brains were isolated and scanned en-bloc using micro-CT (8 μm)3 or nano-CT at 500 nm3 voxel size to generate 3D images of the cerebral vasculature. The arterial vascular volume fraction and gray scale attenuation was determined and the significance of differences in measurements was tested with analysis of variance [ANOVA]. Results Micro-CT provided quantitative information on vascular morphology. Micro- and nano-CT proved to visualize and differentiate vascular occlusion territories performed in both models of cerebral ischemia. The suture technique leads to a remarkable decrease in the intravascular volume fraction of the middle cerebral artery perfusion territory. Blocking the medial cerebral artery with macrospheres, the vascular volume fraction of the involved hemisphere decreased significantly (p Conclusion Micro- and Nano-CT imaging is feasible for analysis and differentiation of different models of focal cerebral ischemia in rats.</p
Active regulation of cerebral venous tone: simultaneous arterial and venous transcranial Doppler sonography during a Valsalva manoeuvre
The aim of this study was to analyse the cerebral venous outflow in relation to the arterial inflow during a Valsalva manoeuvre (VM). In 19 healthy volunteers (mean age 24.1 +/- 2.6 years), the middle cerebral artery (MCA) and the straight sinus (SRS) were insonated by transcranial Doppler sonography. Simultaneously the arterial blood pressure was recorded using a photoplethysmographic method. Two VM of 10 s length were performed per participant. Tracings of the variables were then transformed to equidistantly re-sampled data. Phases of the VM were analysed regarding the increase of the flow velocities and the latency to the peak. The typical four phases of the VM were also found in the SRS signal. The relative flow velocity (FV) increase was significantly higher in the SRS than in the MCA for all phases, particularly that of phase IV (p < 0.01). Comparison of the time latency of the VM phases of the MCA and SRS only showed a significant difference for phase I (p < 0.01). In particular, there was no significant difference for phase IV (15.8 +/- 0.29 vs. 16.0 +/- 0.28 s). Alterations in venous outflow in phase I are best explained by a cross-sectional change of the lumen of the SRS, while phases II and III are compatible with a Starling resistor. However, the significantly lager venous than the arterial overshoot in phase IV may be explained by the active regulation of the venous tone