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1.
BackgroundCarotid artery dissection (CAD) is a significant cause of ischemic stroke. Early recognition and treatment of CAD is important to prevent accompanying cerebral ischemia. This case report presents an atypical clinical presentation of CAD and emphasizes the diagnostic challenge for emergency physicians.Case ReportA 54-year-old woman presented to the emergency department with a bilateral headache of 4 days’ duration, hypesthesia of the left fifth cranial nerve, dysgeusia, and partial Horner syndrome on the left side. Magnetic resonance angiography showed a left-sided CAD without any signs of cerebral ischemic events. Antiplatelet therapy with clopidogrel was started, and the patient did not show any deterioration in the weeks thereafter.Why Should an Emergency Physician be Aware of This?CAD can present with different combinations of cranial nerve palsies and should be in the differential diagnosis of dysgeusia and hypesthesia of the trigeminal nerve. Early recognition of CAD can be challenging in patients with rare cranial nerve involvement, but early treatment is crucial to prevent cerebral ischemic events.  相似文献   
2.
目的 探讨不同类型的责任血管及压迫特点对原发性三叉神经痛手术疗效的影响。方法 回顾性分析2002~2012年微血管减压术治疗的212例原发性三叉神经痛的临床资料。根据术中发现责任血管类型分为动脉压迫(155例)、静脉压迫(24例)和混合压迫(33例),根据术中发现责任血管压迫特点分为接触压迫型(123例)和粘连包裹型(89例)。结果 手术总有效率为95.8%,动脉压迫、静脉压迫和混合压迫有效率分别为98.1%、95.8%和84.8%,接触压迫型和粘连包裹型有效率分别为98.4%和92.1%。结论 微血管减压术是治疗原发性三叉神经痛的有效方法,动静脉混合压迫以及术中粘连包裹可能是影响手术疗效的因素。  相似文献   
3.
原发性三叉神经痛是三叉神经分布区内短暂的发作性剧痛,多发于中老年人,40岁以上患者占70%~80%,发作时表现为面颊上下颌及舌部明显的剧烈电击样、针刺样、刀割样疼痛,持续时间短,突发突止,间歇期完全正常。中医将其归属于"面痛"范畴,多从风热立论,笔者跟随导师临证过程中,发现《医宗金鉴》的芎芷石膏汤治疗风热上犯型原发性三叉神经痛效果显著。  相似文献   
4.
Neuropeptide Y (NPY) is one of a number of neuropeptides with powerful orexigenic effects. Intracerebroventricular administration of NPY induces increases in food intake and alters feeding rate. Besides it role in feeding behavior, NPY also has significant effects on neuronal systems related to other spontaneous behaviors such as rearing and grooming. In the present study, we examined the direct effects of NPY on mesencephalic V neurons (Mes V), which are important sensory neurons involved in oral motor reflexes and rhythmical jaw movements, as well as masticatory proprioception. Coronal brain slices were prepared from neonatal Sprague-Dawley rats (P3-17) and whole-cell patch clamp recordings were obtained from Mes V neurons. Bath application of NPY depolarized the membrane potential and induced inward current in most neurons. Application of NPY shortened the duration of the afterhyperpolarization following an action potential, and increased the mean spike frequency during repetitive discharge. In those neurons which exhibited rhythmical burst discharge in response to maintained current injection, the bursting frequency was also increased. These effects were mediated predominately by both Y1 and Y5 receptors.  相似文献   
5.
This study tested the effect of short‐term tooth‐clenching on corticomotor excitability of the masseter muscle using transcranial magnetic stimulation (TMS). Fifteen subjects with normal stomatognathic function participated. All subjects performed a tooth‐clenching task (TCT) on five consecutive days. The TCT consisted of 10, 20, and 40% of maximum voluntary contraction in a randomized order within 1 h. All subjects underwent TMS in four sessions: pretask day 1 (baseline), post‐task day 1, pretask day 5, and post‐task day 5. Motor‐evoked potentials (MEPs) from the masseter and the first dorsal interosseous (FDI) muscles were obtained using TMS in four sessions. Motor thresholds decreased, after the TCT, for the masseter muscle MEPs. Masseter muscle MEPs were dependent on stimulus intensity and on session, whereas FDI muscle MEPs were only dependent on stimulus intensity. Post‐hoc Tukey tests demonstrated significantly higher masseter muscle MEPs post‐task on day 5 with 80 and 90% stimulus intensity and above when compared with pre‐ and post‐task day 1 values. Our results suggest that the performance of repeated TCTs can trigger neuroplastic changes in the corticomotor control of the jaw‐closing muscles and that such neuroplastic changes may contribute to the mechanism underlying the clinical manifestations of tooth clenching.  相似文献   
6.
Orbital and retro‐orbital pain are relatively common clinical conditions that are associated with such disorders as trigeminal, lacrimal, and ciliary neuralgia, cluster headaches, paroxysmal hemicrania, inflammatory orbital pseudotumor, trochleitis, and herpetic neuralgia ophthalmicus, thus making the nerves supplying the orbit of great clinical importance. Surprisingly, how pain from this region reaches conscious levels is enigmatic. Classically, it has been assumed that pain reaches the ophthalmic division of the trigeminal nerve (V1) and travels to the descending spinal trigeminal nucleus. However, exactly where the receptors for orbital pain are located and how impulses reach V1 is speculative. In this project, we reviewed all of the reported connections between the orbital nerves and V1 in order to understand how pain from this region is transmitted to the brain. We found reported neural connections to exist between cranial nerve (CN) V1 and CNs III, IV, and VI within the orbit, as well as direct neural branches to extra‐ocular muscles from the nasociliary, frontal, and supraorbital nerves. We also found reported neural connections to exist between the presumed carotid plexus and CN VI and CN V1, CN VI and CN V1 and V2, and between CN V1 and CN III, all within the cavernous sinus. Whether or not these connections are sympathetic or sensory or some combination of both connections remains unclear. An understanding of the variability and frequency of these neural connections could lead to safer surgical procedures of the orbit and effective treatments for patients with orbital pain. Clin. Anat. 27:169–175, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
7.
IntroductionVertebrobasilar insufficiency (VBI) is a condition that results from restricted blood flow to the posterior portions of the brain, which are primarily served by the vertebral and basilar arteries. It is the most common cause of vertigo in the elderly and is usually accompanied by impaired vision and sensation. Congenital abnormalities, atherosclerosis, stroke and/or trauma may all lead to decreased vertebrobasilar circulation. A syndrome called Subclavian Steal Syndrome (SSS), which manifests with similar neurological symptoms but with a different pathophysiology, may also cause VBI.Case presentationA middle-aged female presented with gradual onset fainting and vertigo attacks. Cardiac, auditory and autonomic etiologies were investigated and excluded. Clinical findings and presentation were highly suggestive of subclavian steal. However, subsequent CT angiography showed normal subclavian arteries. Instead, findings included a persistent right trigeminal artery (PTA), stenosis of the right proximal internal carotid artery, atresis of the left vertebral artery and distal segment of right vertebral artery, congenitally compromised changes in vertebral circulation (bilateral absence of the posterior communicating arteries (PCOMs)) and an absent anterograde vertebrobasilar circulation. Symptoms resolved after carotid endarterectomy.DiscussionDue to the absence of a normally developed posterior circulation, the PTA was the main source of blood supply for the patient. Development of recent artheromatous changes in the right internal carotid artery, however, resulted in decreased blood through PTA, further compromising posterior circulation. This resulted in vertebrobasilar insufficiency, and manifested in symptomology similar to SSS.ConclusionsThis clinical encounter illustrates the relative contribution of anatomical and vasoocclusive factors in closely mimicking symptoms of subclavian steal syndrome.  相似文献   
8.
静磁场对大鼠三叉神经节中SP-mRNA作用的实验研究   总被引:3,自引:1,他引:3       下载免费PDF全文
目的 探讨静磁场对大鼠三叉神经节中SP-mRNA的影响。方法 将 4 4只 6~ 7周的大鼠置于静磁场中 ,在 1、2、6、1 2和 2 4h时分别将动物处死 ,取其三叉神经节 ,用原位杂交方法研究SP-mRNA在各时间点的变化。结果 在静磁场作用下三叉神经节中SP-mRNA的表达呈上调变化 ,2h时达峰值 ,各时间点与正常对照组间均存在显著性差异 (P <0 0 1 )。结论 静磁场可以使三叉神经节中的SP-mRNA呈现上调性变化。  相似文献   
9.
目的:观察磨除单侧后牙造成单侧咀嚼的大鼠三叉神经节内P物质(substance P,SP)及编码 SP 的前速激肽原 A(PPTA)mRNA 的表达情况,进一步探讨颞颌关节病的发病机制.方法:Wistar 雄性大鼠48只,随机分为6组,包括3个实验组及相应对照组,每组8只.实验组动物磨除右侧上、下颌磨牙,人为造成单侧咀嚼.双侧三叉神经节切片行 SP 免疫组化(SABC法)和原位杂交反应.光镜观察拍片,并用 Image Pro Plus 5.1 图像分析软件进行测定.结果与对照组比较,用SPSS10.0软件进行统计分析.结果:每一实验组咀嚼侧和非咀嚼侧三叉神经节内 SP 免疫阳性神经元百分比与各自对照组比较显著降低(p<0.01,p<0.05),非咀嚼侧明显低于咀嚼侧(P<0.01,p<0.05).原位杂交结果显示,每一实验组咀嚼侧与非咀嚼侧三叉神经节中 PPTAmRNA 阳性神经元的数量较各自对照组明显增高(p<0.01),非咀嚼侧明显高于咀嚼侧(p<0.01,p<0.05).结论:三叉神经节内 SP 和 PPTAmRNA 参与了单侧咀嚼引起的颞颌关节病的病理过程,且两侧三叉神经节内SP释放量、PPTAmRNA 合成量不同.  相似文献   
10.
目的:探讨改进的三叉神经周围支撕脱术治疗老年人原发性三叉神经痛的临床疗效.方法:在三叉神经周围支撕脱术的基础上,采用局部骨碎块填塞神经孔治疗32例老年原发性三叉神经痛患者,其中第Ⅱ支17例,第Ⅲ支10例,第Ⅱ、Ⅲ支5例,均为单侧病变.结果:本组术后随访观察最长6年,最短5个月,显效12例,有效16例,无效4例,有效率87.5%.术后患者撕脱神经所支配区域的面部遗有不同程度的感觉麻木,无其它并发症.结论:改进撕脱术是一种治疗老年人原发性三叉神经痛简单、安全而有效的方法.  相似文献   
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