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11.
伽玛刀治疗听神经瘤(附98例分析)   总被引:1,自引:0,他引:1  
目的 评价伽玛刀治疗听神经的效果。方法 应用OUR旋转式伽玛刀治疗听神经98例。肿瘤直径512~29.7min.平均18.8mm。采用多个放射中心联合照射,周边等剂量曲线为45%-70%,边缘剂量10-13Gy。结果 81例获14。84个月随访,平均39个月。MRI示41例(50.6%)肿瘤缩小,38例(46.9%)无变化,2例(2.5%)增大;25例(30.9%)肿瘤中心失增强。无面瘫和面部麻木,听力保留率59.2%。结论 伽玛刀对听神经瘤有较高的肿瘤控制率,并能保留有用听力,对面神经、三又神经损伤小,是小至中等大小听神经瘤可供选择的治疗方法,及术后残余和复发肿瘤的重要辅助治疗手段。  相似文献   
12.
Acoustic rhinometry measures nasal cavity geometry by analysis of reflected acoustic impulses. Previously, the technique has been applied to normals, patients with septal deviations and rhinitis and to monitor the medical treatment of nasal polyps. To date, no study has been published to validate the application of this technique where nasal polyps are present. In this study, acoustic rhinometry has been used to assess the change in nasal cavity volume following intra-nasal polypectomy in 20 subjects. The volumes of the polyps removed surgically were measured by displacement and compared with the volume change recorded by acoustic rhinometry. A correlation of r = 0.59 (P= <0.01) has been obtained. Therefore, it is possible to apply acoustic rhinometry as a method of assessing non-surgical treatment of nasal polyps given certain conditions.  相似文献   
13.
脑干听觉诱发电位诊断听神经瘤的假阳性分析   总被引:1,自引:0,他引:1  
综合分析BAEP各项指标,应用CPA病变的BAEP4型诊断标准,从600例可疑听神经瘤患者中,诊断出CPA肿瘤54例,同时发现4例假阳性。本文的假阳性率为7%(4/58),较多数文献报道为低。在诊断听神经瘤中,BAEP的峰间期比波的绝对潜伏期准确,只有Ⅰ~Ⅲ峰间期增大所导致的Ⅰ~Ⅴ峰间期增大,才有诊断价值,BAEP只有定位作用,无定性价值,故BAEP诊断听神经瘤必须结合临床表现才有意义。在临床上即使已有明确的长束征时,但BAEP无健侧Ⅳ~Ⅴ波的改变,仍可排除肿瘤的诊断。在BAEP的Ⅳ型中,当健侧Ⅳ~Ⅴ波正常时,应参考复合检查,若其阴性则可排除肿瘤的诊断。  相似文献   
14.
“C”型曲线的中耳声学特性改变与鼓室积液的关系   总被引:10,自引:2,他引:8  
对40耳声导抗检查为“C”型曲线患耳进行中耳系统共振频率点测试并进行鼓室穿刺抽液,结果表明:共振频率点低于600Hz,患耳鼓室积液阳性率为82.1%,高于600Hz患者鼓室和液阳性率16.7%,提示依据鼓室导抗图和共振频率点测定可初步判断“C”型曲线患耳鼓室积液的可能.  相似文献   
15.
The connectivity of a region surrounding the established thalamic auditory nuclei, n. ovoidalis (Ov) and n. semilunaris parovoidalis (SPO), was explored in the ring dove by using the anterograde tracers, Phaseolus vulgaris leucoagglutinin (PHAL) and biocytin, and the retrograde tracer, fluorogold. The Ov-SPO surround received a projection from a cell group along the interface of the auditory midbrain and the n. intercollicularis, as revealed with PHAL and biocytin, and was composed of neurons exhibiting a common morphology. These features and the presence of overlapping projections from different portions of the Ov-SPO surround suggest that this region comprises a functionally discrete area, which we term the Ov shell. Single unit recording within the shell established the existence of acoustically responsive units. Both PHAL and fluorogold labeling revealed a robust projection from the Ov shell to the caudomedial hypothalamus. Major telencephalic projections of the shell terminated within the ventral paleostriatal complex, "end-zones" of the field L, the caudomedial hyperstriatum ventrale, and regions immediately dorsal and lateral to the auditory neostriatum. Except for a portion of the shell bordering medial ovoidalis, PHAL injections into the shell also labeled fibers within the caudolateral neostriatum and along the lateral neostriatal rim. The connectivity of the Ov shell suggests that this region may integrate auditory pathways with brain regions associated with endocrine mediated behavior. In addition, the shell may constitute a source of converging input to several levels of central auditory pathways.  相似文献   
16.
Variable constitutional mosaicism, mos45,XY,-22/46,XY,-22,+mar/46,XY,-22,+r(22)/47,XY,-22,+r(22)+mar/ 47, XY,-22,+r(22)*2, was found in PHA-stimulated peripheral blood, in a lymphoblastoid cell line and in cultured skin fibroblasts from a mentally retarded patient with neurofibromatosis. Both the ring chromosome and the small extra marker chromosome stained positively by in situ hybridization with a chromosome 14/22-specific alphoid repeat probe. DNA dosage analysis showed constitutional loss of one copy of the arylsulfatase A gene (ARSA), consistent with its terminal location on 22q. There was no evidence of constitutional loss of D22S1 or D22S28 which flank the neurofibromatosis type 2 (NF2) locus. Analysis of two DNA samples from a skin neurofibroma indicated retainment of two copies of D22S1, whereas the results were ambiguous with respect to tumor-specific loss of one copy of D22S28. It is suggested that the development of neurofibromatosis of unclear type in two r(22) carriers might be associated with somatic mutation of the NF2 locus due to instability of the ring chromosome(s), and in analogy, that somatic mutation of either NF1 or NF2 may account for some cases of neurofibromatosis which do not meet the criteria of either NF1 or NF2. The occurrence of seminoma in the proband may be fortuitous, but could also be due to the presence of a seminoma-associated locus on chromosome 22.  相似文献   
17.
内耳门周结构对内镜下脑桥小脑三角区手术的影响   总被引:3,自引:3,他引:3  
目的:研究内耳门周结构对颞骨径路内镜下处理脑桥小脑三角区病变手术的影响,为临床开展相应手术提供参考。方法:在20例40侧成人尸头上模拟颞骨径路内窥镜手术,观察小脑下前动脉及内耳门后唇的变异,了解其对内窥镜导入及其手术的影响。结果:内耳门后唇隆起超过面神经脑桥小脑角段1/3以上者占27.5%(11侧)。小脑下前动脉在Ⅶ、Ⅷ脑神经外侧成袢者占22.5%(9侧)。内耳门后唇隆起合并小脑下前动脉袢在Ⅶ、Ⅷ脑神经之外侧者占7.5%(3侧)。结论:当内耳门后唇隆起超过面神经脑桥小脑角段1/3或小脑下前动脉弓在Ⅶ、Ⅷ脑神经之前时将对内窥镜导入有阻碍,当两种情况合并存在时要将内窥镜导入脑桥小脑三角区相当困难,不宜采用此种手术方式。  相似文献   
18.
Nasal patency shows spontaneous variations but is influenced by a number of factors like exercise and allergic conditions. Nasal histamine challenge has been used to define nasal hypersensitivity. We have applied acoustic rhinometry as a new objective method to study the spontaneous variations of the nasal mucosa and its response to histamine challenge in 12 nonallergic subjects and 12 subjects with nasal allergy to pollen, but out of the pollen season. Measurements of the minimum cross-sectional area and the volume of the nasal cavities were done every 15 min for 6 h. More pronounced spontaneous variations, defined by the coefficient of variation of the measurements, were encountered in the allergic than in the nonallergic subjects, especially with regard to the minimum cross-sectional areas in the nasal cavities (P < 0.02). Allergic subjects showed increased sensitivity to histamine, as compared with nonallergic subjects, during low-concentration (0.1%) challenge (P < 0.05) and a prolonged effect of histamine challenge (P = 0.01). Antihistamine (cetirizine) had a significant effect on the histamine-induced symptoms and decrease of nasal dimensions during histamine challenge, but no significant effect on pollen-induced changes. In the allergic group, the decrease in minimum area during allergen provocation correlated with the level of specific IgE (r = 0.81; P = 0.0015).  相似文献   
19.
The effect of circulation arrest on the development of stress-induced injuries was studied in Krushinsky—Molodkina rats genetically predisposed to audiogenic seizure. Resuscitated rats were subjected to acoustic stress 1.5 month after circulation arrest. The severity of neurological disorders and the frequency and severity of intracranial hemorrhages increased, while excitability of the central nervous system remained unchanged during stress. Thus, the resistance to stress considerably decreased in rats survived a short-term circulatory arrest due to dysfunction of the autonomic nervous regulation of hemodynamics rather than enhanced excitability of the central nervous system. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 130, No. 7, pp. 17–19, June, 2000  相似文献   
20.
目的 本研究旨在探讨学龄期脑瘫儿童在连续语音下的言语流利性特征及其与言语可懂度之间的相关性,为脑瘫儿童言语流利性的评估与康复提供理论依据。方法 于2021年1—2月分别纳入学龄期痉挛型脑瘫儿童与同年龄段正常发育儿童各15名,分析其在朗读语音均衡式材料下的言语流利性相关声学参数,包括言语速率、构音速率、平均停顿时长、异常停顿次数和重复次数,再通过转录法计算其言语可懂度。并将言语流利性参数与言语可懂度分数进行Spearman相关性分析。结果 脑瘫组的言语速率、构音速率、言语可懂度显著小于正常对照组(t=-21.650,-15.440,-4.447,P<0.05);平均停顿时长、异常停顿次数、重复次数显著大于正常对照组(t=19.639,20.347,3.767,P<0.05)。脑瘫儿童的言语速率(r=0.831)、构音速率(r=0.827)与言语可懂度均呈正相关(P<0.01);平均停顿时长(r=-0.849)异常停顿次数(r=-0.783)、重复次数(r=-0.672)与言语可懂度均呈显著负相关(P<0.01)。结论 痉挛型脑瘫儿童的言语可懂度降低,言语流利性存在异常,体现在语速减慢、停顿次数、停顿时长与重复次数增加。痉挛型脑瘫儿童的言语流利性与言语可懂度呈正相关,在脑瘫言语治疗中应合理加入改善言语流利性的训练。  相似文献   
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