前庭诱发肌源性电位的临床应用

目的 探讨前庭诱发肌源性电位(VEMP)各参数的临床应用价值.方法 用95 dB nHL短纯音对30例正常人及14例眩晕患者进行前庭诱发肌源性电位的检测,比较2组波形的引出率、潜伏期、振幅、潜伏期差、耳间振幅比及不对称率.结果 健康组p13和n23波引出率为100％,而眩晕组有79％不能正常引出,主要表现为波形未引出、波幅降低、两耳振幅比增大、潜伏期延长及双耳不对称率增大.结论 VEMP的引出率、潜伏期差、耳间振幅比及不对称率具有临床实用性,可作为VEMP异常判断的指标.     

前庭诱发的肌源性电位新进展

前庭诱发的肌源性电位可以监测传导性聋患者、颈肌肌力弱的老年人及幼儿的前庭下神经和球囊功能,评估脑干功能.本文就近年来新开展的采用不同方式诱发和在不同肌肉上记录的前庭诱发肌源性电位进行综述.     

颈性前庭诱发肌源性电位正常值及影响因素的探讨

目的探讨颈性前庭诱发肌源性电位(C-VEMP)在正常人群中的正常参考值和影响因素。方法使用Bio-logic Navigator RRO听性脑干反应诊断系统进行颈性C-VEMP测试,分别进行3种体位测试,并对获得的数据进行统计学分析。结果 110例健康志愿者接受了C-VEMP测试。扭颈测试体位双侧P1潜伏期、N1潜伏期差异均无统计学意义(P值均>0.05);双侧波幅数值相比,差异有统计学意义(P<0.001),左侧波幅普遍高于右侧。伸下颌测试体位,双侧P1潜伏期、N1潜伏期差异均无统计学意义(P值均>0.05);双侧波幅数值相比,差异有统计学意义(P<0.001),左侧波幅普遍高于右侧。收下颌测试体位,双侧P1潜伏期、N1潜伏期差异均无统计学意义(P值均>0.05);双侧波幅数值相比,差异无统计学意义(P=0.443),即双侧波幅相仿。扭颈、伸下颌和收下颌3种测试体位校准前后,波幅比差异均无统计学意义(P值均>0.05)。双侧反应阈值相比,差异无统计学意义(P=0.21)。结论 C-VEMP影响因素较多,使用收下颌测试体位具有较明显的优势,尽管校准存在理论必要,但是实际校准对整体而言无显著差别。     

前庭型偏头痛 102 例临床特征分析

目的总结前庭型偏头痛的临床表现、检查和治疗效果。方法回顾分析2012年12月～2013年9月确诊为前庭型偏头痛的102例患者的临床资料。年龄7～71岁,平均42．2岁。结果男女比例为1：4．1,30—60岁是发病高峰。33．3％（34／102）有家族发病史。眩晕多数为数月发作1次,眩晕持续时间多为数分钟到数日。76．5％（78／102）能提供可能的诱因,14例主诉怕冷。只有9．8％患者主诉头痛。14例变动体位诱发眩晕,28例有晕车史。79例听力正常;28例完成平衡台检查,前庭功能17例正常、11例异常。随访中5例为继发良性阵发性位置性眩晕。10例完成颈性前庭诱发肌源性电位检查,结果均正常。84．3％患者曾误诊,多为梅尼埃病。35例仅采取饮食和生活方式改变,避免触发因素控制症状,67例采用药物治疗。结论前庭型偏头痛患者常不主诉头痛,容易漏诊、误诊,认识偏头痛伴随症状有助诊断。改变饮食和生活方式,结合药物治疗,眩晕和头痛都可迅速得到控制。     

上睑下垂患者提上睑肌组织病理学评价和临床相关性研究

目的 探讨上睑下垂患者提上睑肌组织病理学评价和临床病情的相关性。方法 前瞻性病例研究。纳入2014年1月至2020年6月于我院就诊的125例(125只眼)上睑下垂患者为研究对象;根据病程严重程度分为重度组(50例)和中度组(75例)。在手术过程中获得了125例上睑肌腱膜病标本并进行苏木精-伊红染色、Van Gieson染色、Masson染色、免疫组织化学和透射电镜观察,以观察提上睑肌肌腱膜的病理学特征;使用曼恩·惠特尼(Mann-Whitney)的U检验和多元线性回归进行统计分析,探讨上睑下垂患者提上睑肌组织病理学特征与临床病情的相关性。结果 透射电子显微镜两组患者均存在胶原纤维增生和细胞变性,包括线粒体肿胀和增生,液泡,脂质滴,脓疱核,染色体凝集,细胞器分解,髓样体和自噬体。两组患者提上睑肌腱膜病理学特征脂肪浸润、横纹肌肌纤维丢失、胶原纤维增生、肌红蛋白分布、提上睑肌厚度组间比较存在差异(P <0.05)。Logistics回归表明脂肪浸润(OR=1.816)、横纹肌肌纤维丢失(OR=2.856)、胶原纤维增生(OR=0.301)是影响上睑下垂患者临床病情的影响因子。结论 上睑...     

活血素治疗前庭性眩晕的疗效观察

目的观察活血素(Vasobral;二氢麦角隐亭)口服液治疗前庭性眩晕患者的疗效及毒副反应.方法采用双盲随机法对318例16～74岁的前庭性眩晕患者分为活血素口服液(A组,下同)、利多卡因静脉滴注(B组,下同)、两药联合应用(C组,下同)3组进行治疗,并予疗效观察.结果治疗结果提示,A组的总有效率为89.1%,B组的总有效率为68.9%,C组的总有效率为92.2%,经统计学Ridit检验A组、C组较B组有非常显著差异(p＜0.01);而A、C组间无显著差异(p＞0.05).结论临床观察表明,活血素口服液治疗前庭性眩晕较之利多卡因静脉滴注有显著差异(p＜0.01);两药联用虽无显著意义(p＞0.05),但有增强疗效,并可减少活血素治疗的毒副作用.     

体觉性耳鸣的临床研究

目的 探讨体觉性耳鸣的临床表现、诱发因素及对听力的影响.方法 分析2009年5月～2011年5月本科接诊的33例体觉性耳鸣患者的临床资料,对每位患者行纯音听阈测定.结果 33例体觉性耳鸣患者均有耳鸣伴眩晕,部分患者有耳闷胀感、颈肩痛、面部及下颌痛、头颈部肌肉痉挛及头痛等表现.患者发病前有明确的头颈部创伤病史等因素是体觉性耳鸣的诱发因素.患耳纯音听阈测定与健耳相比较,差异无统计学意义(P＞0.05).结论 体觉性耳鸣有较特征性的临床表现及诱发因素,对听力的影响不明显.     

慢性中耳炎变温试验眼震电图结果的分析和校正

目的探讨视频眼震电图检查的变温试验在慢性中耳炎患者外周前庭功能诊断中的正确应用。方法统计分析60例慢性中耳炎患者的变温性眼震电图表现,并将患耳冷热气诱发的眼震方向和强度以及计算机内置公式（用眼震相对数值计算）和校正公式（用眼震绝对数值计算）计算出的半规管兴奋性不对称比和优势偏向比的结果进行对比。结果患耳或病变较重侧耳热气可诱发出正常方向眼震18例,反向眼震30例,未诱发出眼震12例;冷气可诱发出正常方向眼震57例,未诱发出眼震3例,无反向眼震者。患耳（有鼓膜穿孔）冷热气诱发眼震的强度差异有统计学意义（P〈0．05）,健耳冷热气诱发眼震的强度差异无统计学意义（P〉0．05）。在热气诱发出患耳反向眼震的患者中,应用眼震的绝对数值计算半规管兴奋性不对称比,而只将方向带入优势偏向比的计算,会得出基本符合患者双耳眼震强度和方向性的结果。结论变温性眼震电图在慢性中耳炎前庭功能的诊断中需要根据患者病史、体征和检查数据进行综合分析,在有反向眼震出现时要对计算公式进行校正,才能得出正确的结论。（中国眼耳鼻喉科杂志,2010,10：82-84）     

胸锁乳突肌肌筋膜瓣在腮腺手术中的应用

目的 探讨预防腮腺手术后发生耳颞神经综合征(auriculotemporal syndrome)的简便方法.方法 对11例患者腮腺肿块术后用胸锁乳突肌肌筋膜瓣覆盖创面;另外收集15例腮腺手术后未行胸锁乳突肌肌筋膜瓣修补的患者为对照组,比较两组耳颞神经综合征发生率.结果 11例用肌筋膜瓣覆盖的患者随访半年至1年,术后均未发生耳颞神经综合征;对照组有13例在3个月至半年内发生此综合征.结论 胸锁乳突肌肌筋膜瓣覆盖创面,是防治耳颞神经综合征的有效方法之一.(中国眼耳鼻喉科杂志,2007,7:108～109)     

标准化银杏叶提取物(Egb 761)治疗前庭周围性眩晕的疗效观察

目的了解标准化银杏叶提取物(Egb761)用于治疗前庭周围性眩晕的疗效.方法采用随机对照的方法,选用甲磺酸倍他司汀为对照药,疗程12周.结果研究组患者治疗第12周末眩晕发作频率、持续时间以及眩晕症状总体评分经Wi1coxon秩和检验均显著优于对照组,p值均小于0.05.经12周的治疗,两组患者间治疗总有效率无显著性差异;显效率差异显著,研究组为44.8%(13/29),对照组为12.9%(4/31),x2=7.520,p=0.006.结论标准化银杏叶提取物(Egb761)能有效治疗前庭周围性眩晕.     

Properties of visual evoked potentials to onset of movement on a television screen

In 80 subjects the dependence of movement-onset visual evoked potentials on some measures of stimulation was examined, and these responses were compared with pattern-reversal visual evoked potentials to verify the effectiveness of pattern movement application for visual evoked potential acquisition. Horizontally moving vertical gratings were generated on a television screen. The typical movement-onset reactions were characterized by one marked negative peak only, with a peak time between 140 and 200ms. In all subjects the sufficient stimulus duration for acquisition of movement-onset-related visual evoked potentials was 100ms; in some cases it was only 20ms. Higher velocity (5.6°/s) produced higher amplitudes of movement-onset visual evoked potentials than did the lower velocity (2.8°/s). In 80% of subjects, the more distinct reactions were found in the leads from lateral occipital areas (in 60% from the right hemisphere), with no correlation to handedness of subjects. Unlike pattern-reversal visual evoked potentials, the movement-onset responses tended to be larger to extramacular stimulation (annular target of 5°–9°) than to macular stimulation (circular target of 5° diameter).Abbreviation PREP pattern-reversal visual evoked potentials     

Correcting myogenic ptosis accompanying extraocular muscle weakness: The “Bobby Pin” procedure

This article evaluates the “Bobby Pin” procedure in the correction of myogenic ptosis accompanying extraocular muscle weakness. We retrospectively reviewed 26 eyelids of 13 patients who underwent “Bobby Pin” procedure for myogenic ptosis accompanying extraocular muscle weakness. We evaluated the patients’ clinical features such as age, etiology of ptosis, symptoms, standard ptosis measurements, associated systemic diseases, additional ophthalmic conditions, complications, and recurrence. Etiology of myogenic ptosis and extraocular muscle weakness was oculopharyngeal dystrophy in 4 (31%) patients, chronic progressive external ophthalmoplegia in 4 (31%) patients, myotonic dystrophy in 2 (23%) patients, and idiopathic in 3 (15%) patients. The mean levator function was approximately 5 mm pre- and post-operatively (range 1 to 12 mm). The mean margin-to-reflex distance 1 increased from –1.1 mm (below the light reflex) pre-operatively to +0.4 mm (above the light reflex) post-operatively. After a mean follow-up of 40 months, only 1 (8%) patient experienced ptosis recurrence. Upper eyelids were symmetric in both contour and height in all patients. Mild superficial keratopathy involving less than 10% of cornea was observed in 4 (31%) patients. The “Bobby Pin” procedure is an effective and long-lasting treatment option for correcting acquired ptosis accompanying extraocular muscle weakness. The procedure is safe, simple, easily learned, time- and cost-effective, and does not require any expensive equipment.     

Two disadvantages of a television system as pattern stimulator for evoked potentials

The use of television systems to generate patterned stimuli for the examination of EPs has disadvantages due to the frame frequency of 50Hz of television sets. Because of this, changes in the pattern last 20 msec, with the result that the variability in EP latencies is larger than in the results obtained by projector systems. Furthermore, 50 Hz noise on the recordings, transmitted through the visual system, may be seen.     

Lateral Geniculate Body Evoked Potentials Elicited by Visual and Electrical Stimulation

Purpose

Blind individuals who have photoreceptor loss are known to perceive phosphenes with electrical stimulation of their remaining retinal ganglion cells. We proposed that implantable lateral geniculate body (LGB) stimulus electrode arrays could be used to generate phosphene vision. We attempted to refine the basic reference of the electrical evoked potentials (EEPs) elicited by microelectrical stimulations of the optic nerve, optic tract and LGB of a domestic pig, and then compared it to visual evoked potentials (VEPs) elicited by short-flash stimuli.

Methods

For visual function measurement, VEPs in response to short-flash stimuli on the left eye of the domestic pig were assessed over the visual cortex at position Oz with the reference electrode at Fz. After anesthesia, linearly configured platinum wire electrodes were inserted into the optic nerve, optic track and LGB. To determine the optimal stimulus current, EEPs were recorded repeatedly with controlling the pulse and power. The threshold of current and charge density to elicit EEPs at 0.3 ms pulse duration was about ±10 µA.

Results

Our experimental results showed that visual cortex activity can be effectively evoked by stimulation of the optic nerve, optic tract and LGB using penetrating electrodes. The latency of P1 was more shortened as the electrical stimulation was closer to LGB. The EEPs of two-channel in the visual cortex demonstrated a similar pattern with stimulation of different spots of the stimulating electrodes. We found that the LGB-stimulated EEP pattern was very similar to the simultaneously generated VEP on the control side, although implicit time deferred.

Conclusions

EEPs and VEPs derived from visual-system stimulation were compared. The LGB-stimulated EEP wave demonstrated a similar pattern to the VEP waveform except implicit time, indicating prosthetic-based electrical stimulation of the LGB could be utilized for the blind to perceive vision of phosphenes.     

The complex interaction between ocular perfusion pressure and ocular blood flow – Relevance for glaucoma

Glaucoma is an optic neuropathy of unknown origin. The most important risk factor for the disease is an increased intraocular pressure (IOP). Reducing IOP is associated with reduced progression in glaucoma. Several recent large scale trials have indicated that low ocular perfusion pressure (OPP) is a risk factor for the incidence, prevalence and progression of the disease. This is a strong indicator that vascular factors are involved in the pathogenesis of the disease, a hypothesis that was formulated 150 years ago. The relation between OPP and blood flow to the posterior pole of the eye is, however, complex, because of a phenomenon called autoregulation. Autoregulatory processes attempt to keep blood flow constant despite changes in OPP. Although autoregulation has been observed in many experiments in the ocular vasculature the mechanisms underlying the vasodilator and vasoconstrictor responses in face of changes in OPP remain largely unknown. There is, however, recent evidence that the human choroid regulates its blood flow better during changes in blood pressure induced by isometric exercise than during changes in IOP induced by a suction cup. This may have consequences for our understanding of glaucoma, because it indicates that blood flow regulation is strongly dependent not only on OPP, but also on the level of IOP itself. Indeed there is data indicating that reduction of IOP by pharmacological intervention improves optic nerve head blood flow regulation independently of an ocular vasodilator effect.     

Effect of Fibroblast Growth Factor 2 on Extraocular Muscle Structure and Function

PurposeMutations in the fibroblast growth factor (FGF) receptor can result in strabismus, but little is known about how FGFs affect extraocular muscle structure and function. These were assessed after short-term and long-term exposure to exogenously applied FGF2 to determine the effect of enhanced signaling.MethodsOne superior rectus muscle of adult rabbits received either a series of three injections of 500 ng, 1 µg, or 5 µg FGF2 and examined after 1 week, or received sustained treatment with FGF2 and examined after 1, 2, or 3 months. Muscles were assessed for alterations in force generation, myofiber size, and satellite cell number after each treatment.ResultsOne week after the 5 µg FGF2 injections, treated muscles showed significantly increased force generation compared with naïve controls, which correlated with increased myofiber cross-sectional areas and Pax7-positive satellite cells. In contrast, 3 months of sustained FGF2 treatment resulted in decreased force generation, which correlated with decreased myofiber size and decreased satellite cells compared with naïve control and the untreated contralateral side.ConclusionsFGF2 had distinctly different effects when short-term and long-term treatments were compared. The decreased size and ability to generate force correlated with decreased myofiber areas seen in individuals with Apert syndrome, where there is sustained activation of FGF signaling. Knowing more about signaling pathways critical for extraocular muscle function, development, and disease will pave the way for improved treatment options for strabismus patients with FGF abnormalities in craniofacial disease, which also may be applicable to other strabismus patients.     

The application of Laplacian analysis in the recording of half-field pattern-onset evoked potentials

The Laplacian operator in electroencephalographic measurements consists of a mathematical combination of the responses from a number of electrodes (e.g., five in a crosswise montage). It enhances activity from sources lying underneath the area covered, relative to activity from outside this area. Thus, by appropriate positioning, the contributions of extrastriate and striate sources can be recorded selectively. To quantify the contribution of each hemisphere to half-field onset evoked potentials, the responses in two Laplacian operators, one over each hemisphere, were analyzed and compared to monopolar derivations and a bipolar derivation between the two hemispheres. Both the Laplacian and bipolar analyses were helpful in interpretation of the responses.     

视觉电生理联合检测对开角型青光眼早期诊断价值

目的探索图形视网膜电图（ＰＥＲＧ）、振荡电位（ＯＰＳ）和图形视觉诱发电位（ＰＶＥＰ）联合检测对开角型青光眼早期诊断的价值。方法对 １２例（２０眼）可疑开角型青光眼、３２例（５３眼）早期开角型青光眼和 ３０例（６０眼）正常人进行上述 ３项检测。结果在可疑开角型青光眼组,上述３项检测的阳性率依次为 ５０％、２０％和 １５％,联合检测的阳性率为６５％;在早期开角型青光眼组阳性率依次为６２． ２６％,４５．２８％和 ２８． ３０％,联合检测为 ８５％。结论联合检测较单一检测阳性率高,对开角型青光眼的早期诊断更有意义。     

视觉电生理联合检测对开角型青光眼早期诊断的临床意义

目的探讨图形视网膜电图(P-ERG)、振荡电位(Ops)和图形视觉诱发电位(P-VEP)联合检测对开角型青光眼早期诊断的价值。方法对60例(105只眼)可疑青光眼、30例(60只眼)正常人进行上述3项检测。结果在可疑青光眼组,上述3项检测阳性率依次为57.1%、33.3%和47.6%,两项以上异常为36.1%,联合检测的阳性率为70.6%。结论视觉电生理联合检测较单一检测阳性率高,对开角型青光眼的早期诊断有意义。