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61.
Auditory and vestibular system findings in patients with vertebrobasilar dolichoectasia 总被引:5,自引:0,他引:5
Impairment of the auditory-vestibular system has been reported in patients with vertebrobasilar dolichoectasia (VBD), but little is known about the underlying cause of the symptoms. Auditory testing (pure tone audiometry, auditory brain stem response and stapedius reflex) and vestibular tests (assessment of nystagmus, eye tracking tests, caloric test and rotational test) were performed in 23 patients with auditory-vestibular symptoms and/or cranial nerve impairment associated with VBD. Specific evidence of auditory and/or vestibular system impairment was observed in 19 cases (83%). Among patients with abnormal test findings, 47% had evidence suggesting peripheral impairment, 16% evidence suggesting central dysfunction, and 37% evidence suggesting both peripheral and central dysfunction. Although compression of the vestibulocochlear nerve plays an important role in the genesis of the auditory-vestibular dysfunction in patients with VBD, mechanism such as brain stem-cerebellar ischemia and impaired blood supply to the vestibular labyrinth may be just as important. 相似文献
62.
63.
《Headache》1993,33(2):98-104
SYNOPSIS
Respiratory sinus arrhythmia is regarded as indicative of cardiac vagal integrity. A ratio of the longest R-R interval to the shortest R-R interval during deep breathing test (E:I ratio) was calculated in controls (n=49), cluster headache (n=33) and CPH (n=4) patients, E:I ratio decreased with age but was not dependent upon sex or upon smoking habits. Furthermore, there were no significant differences as regards E:I ratio between cluster headache patients in and outside a bout, or between patients with right-sided and left-sided headache. However, the E:I ratio was found to be significantly lower in the cluster headache group as such, when compared with controls, but the number of patients disclosing pathological or borderline results was small, 2 and 2, respectively. This may indicate that a putative vagal dysfunction in cluster headache is usually less marked than in patients with e.g. diabetic autonomic neuropathy. Significant attack-related change in the E:I ratio were detected in all individual patients though these changes were not of a uniform nature from individual to individual. E:I ratios were rather high in 3 out of 4 CPH patients examined. However, the number of patients in this group is too small to allow definite statements about the difference between CPH end cluster headache with regard to E:I ratios. There was no significant difference between E:I ratios outside and during a mild, short, mechanically precipitated attack in a single CPH patient. 相似文献
Respiratory sinus arrhythmia is regarded as indicative of cardiac vagal integrity. A ratio of the longest R-R interval to the shortest R-R interval during deep breathing test (E:I ratio) was calculated in controls (n=49), cluster headache (n=33) and CPH (n=4) patients, E:I ratio decreased with age but was not dependent upon sex or upon smoking habits. Furthermore, there were no significant differences as regards E:I ratio between cluster headache patients in and outside a bout, or between patients with right-sided and left-sided headache. However, the E:I ratio was found to be significantly lower in the cluster headache group as such, when compared with controls, but the number of patients disclosing pathological or borderline results was small, 2 and 2, respectively. This may indicate that a putative vagal dysfunction in cluster headache is usually less marked than in patients with e.g. diabetic autonomic neuropathy. Significant attack-related change in the E:I ratio were detected in all individual patients though these changes were not of a uniform nature from individual to individual. E:I ratios were rather high in 3 out of 4 CPH patients examined. However, the number of patients in this group is too small to allow definite statements about the difference between CPH end cluster headache with regard to E:I ratios. There was no significant difference between E:I ratios outside and during a mild, short, mechanically precipitated attack in a single CPH patient. 相似文献
64.
The best anastomotic agent to join nerve ends is controversial. This paper describes a controlled trial between a collagen tube wrap and a tissue glue to anastomose the rat facial nerve. There was no difference in the results using photographic, histological and electrophysiological techniques. 相似文献
65.
将大鼠的腓总神经切断后,进行如下4组实验:A.原位3mm间隙动脉套桥接,B.原位断端外膜缝合,C远侧断端旋转180°3mm间隙动脉套桥接,D远侧端旋转180°外膜缝合。术后12周的电生理学,组织学评价显示,B组神经再生效果最佳,A、C两组接近B组,而D组较差。 相似文献
66.
目的:研究面神经撞击伤后面神经核内生长相关蛋白(GAP-43)的变化及高压氧(HBO)治疗的影响。方法:利用BIM-Ⅱ型生物撞击机致家兔右侧面神经干损伤,应用SP免疫组化染色法观察损伤后1、3、7、14和21天(分别用HBO治疗及不用HBO为对照)面神经核内GAP-43的变化,并用电镜观察面神经干超微结构变化。结果:面神经损伤第1天,伤侧面神经核区GAP-43样免疫反应性神经元(GLIN)开始增多,第14天其增多达到高峰,第21天逐渐下降。HBO治疗组伤后不同时期GLIN的增多明显高于对照组。伤后第21天,与对照组相比HBO组面神经干电镜观察可见较多的新生髓鞘。结论:HBO治疗可使伤后面神经核内GLIN增多,因而有助于面神经损伤后的修复与再生。 相似文献
67.
68.
Sherif M. Hassan Frans G.I. Jennekens George Wieneke Henk Veldman 《Neuromuscular disorders : NMD》1994,4(5-6):489-496
Changes in calcitonin gene-related peptide-like immunoreactivity (CGRP-LI) at the motor endplates of botulinum toxin-paralysed rat muscles were investigated using immunohistochemistry. One day following toxin injection, a dramatic increase in CGRP-LI was detected at the motor endplates and within preterminal axons of the soleus and gastrocnemius muscles. The upregulation of CGRP-LI persisted throughout the period during which muscle fibres were paralysed and new neuromuscular junctions were being formed by the growing sprouts. Decline of CGRP-LI at the motor endplates coincided with clinical recovery. Both up- and down-regulation of CGRP-LI took place earlier in the soleus than in the gastrocnemius muscle. Up-regulation of CGRP-LI was also detected in a subpopulation of motor axons in the sciatic nerves and in the spinal motor neurons innervating the paralysed muscles. These results indicate that levels of CGRP are regulated, at least partly, by changes in the target innervation. They also suggest an important role for CGRP in the regenerative processes following muscle paralysis. 相似文献
69.
目的:介绍带血管蒂前臂后皮神经电缆式移植修复上臂桡神经缺损的应用解剖、手术方法及临床效果。方法:在20侧成人上肢标本上,观测前臂后皮神经及桡侧副动脉的行程及外径,设计以桡侧副动脉为蒂的前臂后皮神经电缆式移植修复上臂桡神经缺损的新术式并应用于临床。结果:前臂后皮神经与桡侧副动脉伴行关系密切,具有形成带血管蒂前臂后皮神经转移的解剖学条件;前臂后皮神经横径2.0cm左右,可切取长度15.0cm左右,折叠后可以修复7.0cm左右的桡神经缺损。同时,术中发现神经供体断端出血活跃,说明带血供的前臂后皮神经移植的血供是可靠的。临床应用8例,神经缺损3.5~6.0cm,随访10个月~3年,效果满意。按陆裕朴介绍的评定标准:优4例,良3例,可1例。结论:该术式转移灵活,操作简单、安全、可靠,对供区影响小,是修复上臂桡神经缺损的一种有用的方法。 相似文献
70.
Scott A. Syverud MD J. Matthew Jenkins MD Robert A. Schwab MD Michael T. Lynch MD Kevin Knoop MD Alexander Trott MD 《Academic emergency medicine》1994,1(6):509-513
Objective: Mental nerve block is frequently used to aid repair of facial lacerations; both percutaneous and intraoral approaches to blocking this nerve are used, but have never been compared. The authors compared the two techniques for pain of administration and effectiveness of anesthesia. Methods: A prospective, randomized, single-blind, crossover study was conducted using ten healthy volunteers aged 22 to 33 years. Patients having prior experience with mental nerve blocks, lidocaine allergy, active oral/facial infection, or previous facial fractures were excluded. Bilateral mental nerve blocks were done using intraoral technique on one side and percutaneous technique on the other. Both techniques were used by the same investigator and were carried out with 27-gauge needles and 2.5 mL of 2% buffered lidocaine at room temperature injected over 20 seconds. The oral mucosa was topically anesthetized with viscous lidocaine for 1 minute prior to intraoral injection. The orders of the blocks and sides of the face anesthetized were randomized. Subjective and objective pain (visual-analog scale), efficacy (anesthesia of lower lip), time to onset, and duration of anesthesia were evaluated. Results: The intraoral technique was subjectively less painful than the percutaneous approach in nine of ten subjects (p = 0.02). Scores on the visual-analog pain scale were significantly lower for the intraoral technique (p = 0.03). Intraoral injection produced lower-lip anesthesia in 10/10 subjects versus 7/10 for percutaneous (p = 0.25). Times to onset (approximately 1–2 minutes) and durations of anesthesia (approximately one hour) were similar for the two techniques. Conclusion: The intraoral approach to the mental nerve block with adjunctive topical anesthesia was subjectively and objectively less painful than the percutaneous approach without adjunctive anesthesia. While the intraoral approach had a greater efficacy of lower-lip anesthesia and a longer duration of action, these differences were not statistically significant. 相似文献