三个半规管阻塞动物模型的建立

目的　旨在建立豚鼠单侧三个半规管阻塞的动物模型。方法　利用 2 0只豚鼠行单侧三个半规管阻塞 ,观察手术前后眼震电图、听性脑干反应 (auditorybrainstemresponses,ABR)、畸变产物耳声发射 (distortionproductotoacousticemissions,DPOAE)及形态学的变化 ,非手术耳作为对照。结果　豚鼠术后 1d出现自发性眼震 ,正弦摆动刺激单侧眼震反应消失 ,侧别与术侧一致 ,术后 30d左相与右相眼震反应对称。术前微量冰水灌注 ,两耳均能引出眼震 ,术后 30d做冰水实验结果为术耳未能引出眼震 ,非术耳出现正常的眼震反应。术后ABR阈值有轻度升高 ,DPOAE反应幅度无明显改变。 8只动物病理切片证实三个半规管完全阻塞而耳蜗Corti器和壶腹嵴结构正常。结论　表明三个半规管阻塞动物模型成功 ,提示三个半规管阻塞术可望成为治疗难治性外周性眩晕的安全有效、操作相对容易的手术方法。     

后半规管阻塞前后豚鼠前庭及耳蜗功能的动态变化

目的 探讨机械性后半规管阻塞前后豚鼠前庭和耳蜗功能的动态变化。方法 采用２０只豚鼠建立单侧后半规管阻塞的动物模型,观察手术前后眼震电图,听性脑干反应,耳声发射等变化。结果 术后第１天,第３天豚鼠正弦摆动刺激术侧眼震反应,明显减术,术后第５天起双侧眼震恢复正常。术后早期ＡＢＲ阈值一度升高,第５天达高峰,ＡＢＲ阈值平均升高４．５ｄＢ。ＤＰＯＡＥ反应幅度无明显改变。结论 后半规管阻塞能选择性地消除后半规     

半规管开窗放置链霉素对正常的膜迷路积水耳的内耳功能…

为探索临床应用氨基甙类药物治疗Ｍｅｎｉｅｒｅ病的途径和可行性，对豚鼠正常耳和人工造成膜迷路积水耳行外半规管开窗放置硫酸链霉素后的内耳功能和形态进行观察。结果表明开窗放药后正常耳耳蜗电图（ＥＣｏｃｈＧ）动作电位（ＡＰ）阈值无变化，积水耳ＡＰ阈值升高，正常耳和积水耳冰水试验眼震消失。光镜下正常耳给药后三个半规管壶腹嵴和椭圆囊斑前庭上皮严重受损，耳蜗毛细胞正常；积水耳用药后前庭上皮受损更重，部分变性、萎     

应用微波技术行后半规管阻塞术的实验研究

目的 :探讨应用微波技术行后半规管阻塞术的可行性。方法 :应用微波技术对 2 0只豚鼠行后半规管阻塞术 ,观察术前、术后豚鼠眼震电图 (ENG) ,听性脑干反应 (ABR)及形态学的变化。结果 :术后第 1天豚鼠正弦摆动刺激时术侧眼震反应减弱 ;术后第 3天双侧眼震恢复对称 ;术后 30 d冰水实验结果显示两耳能引出对称性眼震 ;术后 ABR阈值无明显改变 ;术后 6 0 d病理切片证实后半规管完全阻塞而耳蜗 Corti器和壶腹嵴正常。结论 :应用微波技术行后半规管阻塞术是对后半规管阻塞术的一种有意义的改进方法。     

半规管开窗放置链霉素对正常和膜迷路积水耳的内耳功能和形态学影响

为探索临床应用氨基甙类药物治疗病的途径和可行性，对豚鼠正常耳和人工造成膜迷路积水耳行外半规管开窗放置硫酸链霉素后的内耳功能和形态进行观察。结果表明开窗放药后正常耳耳蜗电图（ＥＣｏｃｈＧ）动作电位（ＡＰ）阈值无变化，积水耳ＡＰ阈值升高，正常耳和积水耳冰水试验眼震消失。光镜下正常耳给药后三个半规管壶腹嵴和椭圆囊斑前庭上皮严重受损，耳蜗毛细胞正常；积水耳用药后前庭上皮受损更重，部分变性、萎缩，耳蜗底回及部分第二回毛细胞亦受损。揭示在膜迷路积水状态下对链霉素的耳毒敏感性增加。     

三半规管阻塞与迷路切除术后前庭功能动态变化

目的：比较豚鼠三半规管阻塞与迷路切除术后前庭功能代偿的异同。材料与方法：将15只健康豚鼠分为2组，其中8只豚鼠行右侧三半规管阻塞术（triple semicircular canal occlusion,TCO)，7只豚鼠行右侧迷路切除术（labyruinthectomy,LE)，于术后一个月内观察豚鼠行为学及眼震电图（ENG）的动态变化，结果：发现术后第1天两组均出现自发性眼震，正弦摆动刺激术侧时未引出衣发性眼震，头向右侧偏斜并沿地面垂直轴向术侧旋转；LE组却出现番滚现象，术后第3，5，10，15，30天正弦摆动眼震试验，两组豚鼠术侧眼震均随时间的推移逐渐恢复，TCO组于15天左右向眼震基本恢复对称，而LE组至术后30天仅摆动幅度120，150度，180度左右向眼震基本对称，摆动幅度为60度，90度双向眼震反应差异仍有显著意义（P＜0．05），。另外，LE组有3只豚鼠仍存在头偏，结论：TCO组要比LE组动物恢复快，建立代偿和失平衡时间短。     

水平半规管良性阵发性位置性眩晕的诊断

目的探讨水平半规管良性阵发性位置性眩晕（BPPV）的诊断。方法自2003年1月至2006年9月，本眩晕中心共确诊为水平半规管BPPV（HSC BPPV）患者46例。诊断依据为典型的病史及用红外视频眼震电图仪记录患者在Dix—Hallpike试验和滚转试验中的眼震结果，并排除其他疾病。研究HSC BPPV的眼震特点。结果441例诊断为BPPV患者中，46例（10．43％）为水平半规管BPPV。其中38例（82．61％）为单侧病变，5例（10．87％）患者合并同侧后半规管病变，3例（6．52％）为双侧病变。35例患者通过两种试验诱发出水平眼震，11例患者仅通过滚转试验诱发出水平眼震。25例患者眼震方向向地，13例患者眼震方向背地，3例患者眼震方向不固定，5例患者各种手法诱发出同一方向的眼震。29例患者在双侧手法中出现眼震，17例患者在一侧手法中出现眼震。结论HSC BPPV眼震为完全水平性且多为快相向地。通常受累耳在双侧手法中均可出现眼震，以向患侧为重。一侧水平半规管和后半规管可同时受累。滚转试验在HSC BPPV检查中比Dix—Hallpike试验更加敏感。Dix—Hallpike试验结合滚转试验可使更多的HSCBPPV患者得到确诊．     

三半规管阻塞与迷路切除术后前庭功能动态变化

目的 :比较豚鼠三半规管阻塞与迷路切除术后前庭功能代偿的异同。材料与方法 :将 15只健康豚鼠分为 2组 ,其中 8只豚鼠行右侧三半规管阻塞术 (triple semicircular canal occlusion,TCO) ,7只豚鼠行右侧迷路切除术(labyrinthectomy,L E) ,于术后一个月内观察豚鼠行为学及眼震电图 (ENG)的动态变化。结果 :发现术后第 1天两组均出现自发性眼震 ,正弦摆动刺激术侧时未引出诱发性眼震 ,头向右侧偏斜并沿地面垂直轴向术侧旋转 ;L E组却出现翻滚现象。术后第 3、5、10、15、30天正弦摆动眼震试验 ,两组豚鼠术侧眼震均随时间的推移逐渐恢复 ,TCO组于 15天左右向眼震基本恢复对称 ,而 L E组至术后 30天仅摆动幅度 12 0°、15 0°、180°左右向眼震基本对称 ,摆动幅度为 6 0°、90°双向眼震反应差异仍有显著性意义 (P <0 .0 5 ) ;另外 ,L E组有 3只豚鼠仍存在头偏。结论 :TCO组要比 L E组动物恢复快 ,建立代偿和失平衡时间短     

豚鼠半规管阻塞术中听性脑干反应的变化

目的：观察正常豚鼠行三个半规管阻塞术中ABR反应阈值的动态变化。方法：健康白色纯种豚鼠10只，分别于术前、打开听泡、开放与阻塞各个半规管后测ABR阈值。结果：三个半规管阻塞结束后，ABR阈值平均升高6．82dB。各个半规管开窗前后ABR阈值上升较明显，而阻塞前后ABR阈值变化不明显。结论：半规管阻塞术中的听力下降是一个渐进的过程，引起听力下降的主要原因可能是外淋巴的流失，迷路受刺激并非造成听力下降的主要因素。     

鼓膜穿孔眩晕者的冷热气试验结果分析

目的：分析冷热气刺激下鼓膜穿孔患者的试验结果特点,探讨鼓膜穿孔者冷热气试验的可行性。方法：慢性中耳炎鼓膜穿孔伴眩晕的患者43例（49耳）,行双耳冷热气试验,观测眼震特点、慢相角速度（SPV）和眼震不对称比（UW）。结果：穿孔耳冷热气刺激诱发眼震呈现4种类型：①增强型：穿孔耳诱发性眼震SPV增强并超过正常范围,或强于非穿孔耳、UW＞15％者15例（17耳）;②“正常型”：穿孔、非穿孔耳眼震SPV均在正常范围,UW〈15％者7例;③减弱型：穿孔耳眼震SPV弱于非穿孔耳,UW〉15％者9例;④反向型：非穿孔耳冷热气刺激眼震正常,穿孔耳热气刺激眼震反向者12例（14耳）。反向型眼震均出现在近期慢性中耳炎复发、鼓膜穿孔且有渗出或潮湿者;其余类型均为慢性中耳炎静止期患者。结论：对于穿孔耳,冷热气成为强刺激,半规管功能正常时诱发的眼震强于非穿孔耳;穿孔耳半规管功能不同程度减弱时,诱发眼震可为正常或减弱反应;活动期的中耳炎患者,穿孔耳热气刺激可转化为冷刺激效应,诱发出反向眼震;冷热气试验可用于鼓膜穿孔伴眩晕患者的前庭功能评定。     

Effects of acute infrasound exposure on vestibular and auditory functions and the ultrastructural changes of inner ear in the guinea pig]

OBJECTIVE: To define the effects of acute infrasound exposure on vestibular and auditory functions and the ultrastructural changes of inner ear in guinea pigs. METHODS: The animals involved in the study were exposed to 8 Hz infrasound at 135dB SPL for 90 minutes in a reverberant chamber. The sinusoidal pendular test (SPT), auditory brainstem response (ABR) and distortion product otoacoustic emissions (DPOAE) were respectively detected pre-exposure and at 0(within 2 hrs), 2 and 5 day after exposure. The ultrastructures of the inner ear were observed by scanning electron microscopy. RESULTS: The slow-phase velocity and the frequency of the vestibular nystagmus elicited by sinusoidal pendular test (SPT) declined slightly following infrasound exposure, but the changes were not significant (P > 0.05). No differences in the ABR thresholds, the latencies and the interval peak latencies of I, III, V waves were found between the normal and the experimental groups, and among experimental groups. The amplitudes of DPOAE at any frequency declined remarkably in all experimental groups. The ultrastructures of the inner ear were damaged to different extent. CONCLUSION: Infrasound could transiently depress the excitability of the vestibular end-organs, decrease the function of OHC in the organ of Corti and cause damage to the inner ear of guinea pigs.     

Triple semicircular canal occlusion in guinea pigs with endolymphatic hydrops.

HYPOTHESIS: Triple semicircular canal occlusion will eliminate rotatory stimulation to the vestibular peripheral system (as it blocks endolymphatic fluid movement) and therefore release rotatory vertigo attack. This surgery is safe in ears with endolymphatic hydrops. BACKGROUND: Semicircular canal occlusion has been used as an alternative treatment of intractable benign paroxysmal positional vertigo with varied success. Triple semicircular canal occlusion in animal models blocks the responses of the semicircular canals to rotation and spares cochleae and the otolithic apparatus. This result suggests that triple semicircular canal occlusion is a prospective method in vertigo management for patients with Ménière's disease. However, the effectiveness and safety of triple semicircular canal occlusion has not been fully evaluated in ears with endolymphatic hydrops. METHODS: Endolymphatic hydrops was established in 20 guinea pigs by endolymphatic sac obliteration. Triple semicircular canal occlusion was performed in 12 of them 120 days after endolymphatic hydrops surgery, whereas 8 others were killed for morphologic observation to confirm endolymphatic hydrops. Auditory and vestibular functions were monitored from the time before endolymphatic hydrops until 1 month after triple semicircular canal occlusion. Endolymphatic hydrops and canal occlusion were confirmed by morphologic observation. RESULTS: Successful establishment of endolymphatic hydrops was indicated by mild elevation of the auditory brainstem response threshold and tentative asymmetry in nystagmus. Endolymphatic hydrops was confirmed by cochlear morphology in all eight animals that were killed 120 days after endolymphatic hydrops surgery. After triple semicircular canal occlusion, all 12 animals showed spontaneous nystagmus with a slow component toward the side that had been operated on, head tilt, rotated walking, and tentative asymmetry in rotatory nystagmus. The static symptoms disappeared within 1 month after triple semicircular canal occlusion. Caloric nystagmus was only slightly reduced after endolymphatic hydrops as compared with the contralateral ears but could not be elicited at all after triple semicircular canal occlusion. No significant elevation in auditory brainstem response threshold was found after triple semicircular canal occlusion. The canal occlusion and endolymphatic hydrops were confirmed in all surgical ears. CONCLUSION: Triple semicircular canal occlusion is effective for eliminating the response of semicircular canals to rotation and caloric stimulation and is safe in ears with endolymphatic hydrops. Also, the static compensation to the disequilibrium is quick and complete. These results suggest that triple semicircular canal occlusion should be an option for controlling rotatory vertigo in Ménière's disease.     

自身免疫性听神经病动物模型的建立及听性脑干反应和畸变产物耳声发射的变化

目的建立自身免疫性听神经病动物模型，探讨其听性脑干反应（auditory brainstem response ABR）和畸变产物耳声发射（distortion product otoacoustic emission DPOAE）的变化特征。方法选取耳廓反射正常的白色豚鼠250只，分离、电泳与纯化豚鼠螺旋神经节及蜗轴内的耳蜗神经纤维抗原，然后与等量完全弗氏佐剂免疫同种豚鼠，其中正常组10只，对照组10只，试验组50只。观察ABR、DPOAE、血清IgG水平、螺旋神经节和耳蜗核团形态学的改变、听神经抗原蛋白在螺旋神经节和耳蜗神经的表达、听神经纤维超微结构的变化。结果免疫后16只动物（32／100耳）出现听性脑干反应阈提高10～25dB，Ⅰ、Ⅲ波潜伏期延长，到免疫后第3周最为明显，随后有逐渐恢复的趋势，其中Ⅲ波潜伏期到第6周恢复正常；该组豚鼠DPOAE没有变化，动物血清IgG显著性升高，与对照组相比差异有统计学意义（F=10．03，P〈0．05）；均有不同程度的螺旋神经节细胞变性、数目减少，螺旋神经节和小血管周围有淋巴细胞浸润；听神经纤维出现脱髓鞘、髓鞘断裂等现象。豚鼠耳蜗核各亚核团平均细胞密度和细胞平均面积各组差异比较没有统计学意义；听神经蛋白完全分布于耳蜗螺旋神经节和听神经纤维组织。免疫后34只动物（68／100耳）没有出现ABR反应阈升高，血清IgG没有升高，与对照组相比差异没有统计学意义，螺旋神经节、耳蜗核团、听神经纤维超微结构没有变化。结论建立了豚鼠自身免疫性听神经病动物模型，该动物模型的ABR反应阈轻中度提高，Ⅰ、Ⅲ波有自然恢复的趋势。DPOAE没有变化。     

急性次声波暴露后豚鼠位听功能及内耳超微结构的变化

目的观察次声波对豚鼠位听功能和内耳超微结构的影响。方法将豚鼠置于频率8Hz、声压级135dBSPL的次声声场中连续暴露90min。应用正弦摆动试验(sinusoidalpendulartest,SPT)、听性脑干反应（auditorybrainstemresponse,ABR）和畸变产物耳声发射(distortionproductionotoacousticemission,DPOAE)评价次声波暴露前后豚鼠前庭功能和听功能的变化,扫描电镜观察豚鼠内耳各结构表面超微形态的变化。结果次声波暴露后不同时间正弦摆动诱发的豚鼠前庭性眼震的最大慢相速度(slow-phasevelocity,SPV)和频率较次声暴露前轻微降低,但无显著性意义(P>0.05)。次声波暴露后各组动物ABR阈值较正常时略有升高,亦无统计学差异(P>0.05),各组动物ABR各波潜伏期和波间期与次声暴露前比较差异均无显著性(P>0.05);DPOAE的幅度值在各个频率段均有明显的降低(P<0.01)。扫描电镜下见各实验组动物内耳半规管壶腹嵴两囊斑及Corti器感觉毛细胞纤毛缺失、散乱、倒伏及融合,表皮板等结构均有不同程度的损伤。结论次声波对豚鼠前庭末梢感受器兴奋性可能有一过性的轻微抑制作用,但SPT无有意义改变。次声波可引起豚鼠内耳毛细胞超微结构的损伤,可导致豚鼠耳蜗外毛细胞功能明显减退,这种功能减退尚不足以引起听力的明显改变。     

交叉听力对豚鼠听性脑干反应测试的影响

报告对８只听觉正常的及鼠，观察交叉听力对其耳蜗动作电位和听怀脑干反应测试结果的影响。先手术造成其左耳全聋，然后用四种方法分别记录ＡＢＲ反应阈和Ⅰ波潜伏期。结果发现，术耳虽已全聋，但该侧给声强度达１０ｄＢＨＬ以上时仍可记录到ＡＢＲ，而ＡＰ未能引出，代之出现的却是清晰的ＡＢＲ波形。     

Effect of high-dose cisplatin on auditory brainstem responses and otoacoustic emissions in laboratory animals

OBJECTIVE: The role of transient evoked otoacoustic emissions (TEOAE) and distortion product otoacoustic emissions (DPOAE) as early indicators of cisplatin-induced ototoxicity in three different rodent species--the guinea pig. the albino rat, and the fat sand rat (Psammomys obesus)--was investigated. In addition, an attempt was made to determine which of the three rodent species is most susceptible to cisplatin-induced ototoxicity as measured by auditory brainstem responses (ABR), BACKGROUND: There have been numerous clinical and experimental reports on cisplatin-induced ototoxicity, but to the authors' best knowledge, there has been no comparative report on the short-term effects of cisplatin on OAE measured with commercially available equipment between different rodent species. METHODS: Cisplatin was systemically administered as a single high dose (12 mg/kg intraperitoneally) to all three species, and the ototoxic effects were measured before and 3 days after the injection of cisplatin in the same animals, using ABR, TEOAE, and DPOAE. RESULTS: The ABR thresholds were significantly elevated in the guinea pigs and the albino rats but not in the sand rats. Significant depression of TEOAE energy and DPOAE amplitude occurred only in the guinea pigs. The depression of the DPOAE was greater than that of the TEOAE. The guinea pigs showed the greatest degree of ototoxicity (depression of ABR and OAE). CONCLUSIONS: Among the three rodent species, the guinea pig has the potential to be used as a sensitive animal model in studies of cisplatin ototoxicity. The study also showed that the recordings of TEOAE and DPOAE, in addition to ABR, are sensitive techniques for the assessment of cisplatin-induced ototoxicity.     

Inner ear changes with intracochlear gentamicin administration in Guinea pigs

OBJECTIVES/HYPOTHESIS: Transtympanic administration of gentamicin is reported to be a useful treatment for vertigo in such conditions as Meniere's disease, and determining appropriate clinical dosage of gentamicin is difficult. The authors examined the relation between gentamicin dosages and inner ear function in guinea pigs. STUDY DESIGN: This study is a basic science project designed to examine cochlear and vestibular function in animal models. METHODS: Various concentrations of gentamicin solution were infused into the right inner ear of guinea pigs by osmotic pumps. Caloric nystagmus as a marker of vestibular function and the change in auditory brainstem response (ABR) threshold as a marker of cochlear function were observed. RESULTS: After 14 days of treatment, high gentamicin concentrations of 40 mg/mL caused canal paralysis and a rapid shift in ABR threshold. Animals exposed to low gentamicin concentrations of 4 mg/mL showed no obvious change in either vestibular or cochlear function. Animals exposed to moderate gentamicin concentrations of 12 mg/mL showed a moderate shift in ABR threshold and caloric malfunction. Histopathological examination revealed that after 14 days of treatment with 40 mg/mL gentamicin, severe cytoplasmic damage occurred in both vestibular and cochlear end organs. In animals treated with 12 mg/mL gentamicin, hair cells remained in the cochlear third turn and ampulla of the lateral semicircular canal. CONCLUSION: The authors established an animal model that showed the moderate damage of inner ear with moderate-dose gentamicin. The study results indicated that the appropriate administration of gentamicin could establish a stable effect on the inner ear. It may be important to select the protocol that delivers a stable dosage of gentamicin to treat patients with Meniere's disease safely and effectively.