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1.
MRI与HRCT的迅速发展以及各种后处理技术的应用使半规管的影像学检查有了显著的进步,本文综述半规管的MRI及HRCT检查新进展。  相似文献   

2.
In a series of six cochlear-implant candidates, including three small children, labyrinthine ossification in various stages of development was observed at CT. In four of the candidates the ossifying process was more advanced in the semicircular canals than in the cochleae, and in two equally distributed. The ossifying process developed during a period of 4–5 months in two of the children. Asymmetry of its extension was found in four patients. The causative organisms were Hemophilus influenzae and Streptococcus pneumoniae. The radiologic assessment of cochlear-implant candidates should include the semicircular canals where the ossification may start, and herald the development of cochlear ossification. Received 9 November 1995; Revision received 17 April 1996; Accepted 25 April 1996  相似文献   

3.
This paper discusses the applicability of a previously developed model of endolymph movement in the semicircular canals of the vestibular apparatus for an adequate interpretation of experimental data concerning the effect of microgravity on thermal responses of the semicircular canal.  相似文献   

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The anatomic variations of the semicircular canals were investigated in a series of 95 plastic temporal bone preparations. The results showed a wider range of variability than has been assumed previously. An intraindividual correlation was found between the sizes of the superior and lateral semicircular canals. Observations indicate why a semicircular canal is not invariably delineated on one tomographic plane despite correct positioning for its optimum reproduction.  相似文献   

7.
Imaging of the semicircular canals specifically is part of the imaging process of the temporal bone in general. The semicircular canals are easily seen on CT images and 3DFT-CISS-weighted MR images, both performed with 1.0-mm-thick slices, or even thinner slices. In selected cases, the T1-weighted images give unique information on the semicircular canals. This article briefly reviews the variety of semicircular canal anomalies that are most frequently present and can be routinely seen on CT and MR examinations of the temporal bone. It also provides a list that can be used by the radiologist in clinical practice to decide which technique, CT or MR, should be used to detect specific anomalies at the level of the semicircular canals.  相似文献   

8.
目的:利用MSCT测量骨性半规管的径线、相互间的角度,椭圆囊的径线及体积,并估算健康成年人前庭器官参考值。方法:对60例健康成人行颞骨MSCT靶扫描及双斜位MPR,以显示各骨性半规管的全程和椭圆囊的全貌,并测量骨性半规管的径线、半规管间夹角以及椭圆囊的长径、短径和体积。用SPSS v16软件进行差异性t检验和参考值估算。结果:①前骨性半规管的内径、高度、跨度的测量值分别为(1.82±0.16)mm、(5.34±0.32)mm、(4.90±0.62)mm;后骨性半规管分别为:(1.57±0.14)mm、(4.89±0.50)mm、(3.06±0.47)mm;外骨性半规管分别为:(2.32±0.31)mm、(2.11±0.46)mm、(3.74±0.44)mm;椭圆囊的长径、短径分别为:(5.01±0.34)mm、(3.51±0.43)mm,体积为(56.7±7.71)mm3。②相应骨性半规管的径线及椭圆囊的体积比较在性别及侧别上差异均无统计学意义(P>0.05);不同半规管间的径线比较差异有统计学意义(P<0.05)。③骨性半规管间夹角测量值:前骨性半规管和后骨性半规管间91.80°±7.18°,前骨性半规管和外骨性半规管间89.71°±4.95°,后骨性半规管和外骨性半规管间91.19°±1.46°。④骨性半规管间夹角比较在性别及侧别上差异均无统计学意义(P>0.05)。结论:①利用MSCT靶扫描结合双斜位MPR可以很好地显示骨性半规管的全程和椭圆囊的全貌。②本组骨性半规管的径线和椭圆囊的测量值处于95%的置信区间内,可以作为正常参考值。③外骨性半规管的内径最大,前骨半规管最小;前骨半规管的高度和跨度最大,外骨半规管最小。骨性半规管间的相互夹角并非严格相互垂直。  相似文献   

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In an investigation of 94 plastic casts of temporal bone specimens a wide range of variations both in the general outline of the pyramid and in the anatomy of its specific structures was found. Attempts were made to estimate the transverse and vertical dimensions of the petrous bone. Both the mastoid and the perilabyrinthine pneumatization correlated to the dimensions of some structures, but not to the size and shape of the semicircular canals.  相似文献   

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BACKGROUND AND PURPOSE: This paper describes the CT findings that characterize the middle and inner ear anomalies in coloboma, heart defects, choanal atresia, mental retardation, genitourinary, and ear anomalies (CHARGE) syndrome. With this information, neuroradiologists will be better prepared to provide clinically relevant information to their referring physicians regarding this rare syndrome. MATERIALS AND METHODS: CT studies from 13 patients were reviewed by 2 neuroradiologists with Certificate of Additional Qualification. Each ear was counted separately for a total of 26 ears. Middle and inner ear anomalies associated with CHARGE syndrome were categorized. Investigational review board approval was obtained. RESULTS: Twenty of 26 (77%) ears demonstrated cochlear aperture atresia. Four of these ears were evaluated with MR imaging and were found to lack a cochlear nerve. Twenty-one of 26 (81%) cochlea had some form of dysplasia. Six of 26 (23%) round windows were aplastic. Three of 26 (12%) round windows were hypoplastic. Twenty-one of 26 (81%) oval windows were atretic or aplastic. Fifteen of 26 (58%) vestibules were hypoplastic or dysplastic. There were 5 of 26 (19%) enlarged vestibular aqueducts. Twelve of 26 (46%) vestibular aqueducts had an anomalous course. All cases demonstrated absent semicircular canals. Twenty-three of 26 (88%) facial nerve canals had an anomalous course. Four of 26 (15%) tympanic segments were prolapsed. Three of 26 (12%) temporal bones had an anomalous emissary vein referred to as a petrosquamosal sinus. Twenty-one of 26 (81%) middle ear cavities were small. Twenty-three of 26 (93%) ossicles were dysplastic with ankylosis. Three of 26 (12%) internal auditory canals were small. CONCLUSION: The CT findings that correlate to the anomalies of CHARGE syndrome affect conductive as well as sensorineural hearing. Stenosis of the aperture for the cochlear nerve aperture on CT is suggestive of hypoplasia or absence of the cochlear nerve, which has been demonstrated in some cases by MR. Absence of the cochlear nerve would be a contraindication to cochlear implantation.  相似文献   

12.
The aim of this study was to assess the role of high resolution multi-detector CT in diagnosis of different dehiscences of the semicircular canals (SCC).  相似文献   

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目的明确在半规管(SCC)完全不发育的耳蜗植入候选者中岩鳞窦(PSS)的出现频率及描述其形态学特征和伴随的颅底异常。材料与方法经伦理委员会的许可后,从一家医学中心1995年—2010年的所有内耳畸形病人的电子数据库中回顾性地选取病例。由神经放射学专家回顾性分析  相似文献   

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多层螺旋CT双斜位MPR对骨半规管的全程显示研究   总被引:6,自引:3,他引:6  
目的:利用多层螺旋CT各向同性扫描进行双斜位多平面重组(multiplanarreformation,MPR)后处理,重建出各半规管全貌。方法:搜集观察对象105例(男52,女53),210耳,年龄范围为9个月至71岁,利用多层螺旋CT各向同性扫描对颞骨进行检查,然后对所得图像进行双斜位多平面重组(multiplanarreformation,MPR)后处理,重建出各半规管全貌。结果:通过双斜位多平面重组(MPR)后骨半规管和外骨半规管均能在一个平面上显示其全貌,部分前骨半规管(105例中6例,5.7%)未能显示全貌。结论:多层螺旋CT各向同性扫描后双斜位多平面重组(MPR)后处理能够很好的显示各骨半规管的全貌。  相似文献   

16.

Purpose:

To assess the ability of magnetic resonance imaging (MRI) to depict the semicircular canals of the inner ear by comparing results from the sampling perfection with application‐optimized contrasts by using different flip angle evolutions (SPACE) sequence with those from the true free induction with steady precession (TrueFISP) sequence.

Materials and Methods:

A 1.5‐T MRI system was used to perform an in vivo study of 10 healthy volunteers and 17 patients. A three‐point visual score was employed for assessing the depiction of the semicircular canals and facial and vestibulocochlear nerves and the contrast‐to‐noise ratio (CNR) was computed for the vestibule and pons on images with the SPACE and TrueFIPS sequences.

Results:

There were no susceptibility artifact‐related filling defects with the SPACE sequence. However, the TrueFISP sequence showed filling defects for at least one semicircular canal on both sides in seven cases for healthy subjects and in 10 cases for patients. The CNR with the SPACE sequence was significantly higher than with the TrueFISP sequence (P < 0.05). There was no statistically significant difference in depicting the facial and the vestibulocochlear nerves (P = 0.32).

Conclusion:

For the depiction of the semicircular canal, the SPACE sequence is superior to the TrueFISP sequence. J. Magn. Reson. Imaging 2013;37:652–659. © 2012 Wiley Periodicals, Inc.  相似文献   

17.
Untreated and treated (unilateral section of utricular and saccular branches of the vestibular nerve) pigeons Columba livia were rotated in the dark in the horizontal plane, the head being in a different position relative to the axis of rotation. The range of angular acceleration was 7-19 deg/c2 and the peak value of centrifugal acceleration was 0.5 g. The neck and eye nystagmus was recorded. It was found that: 1) the result of canal-otolith interaction was not directly related to the pattern of changes of otolith afferentation but was determined by the ratio of otolith afferent signals in the right and left labyrinths and, consequently, by the ratio of patterns of activities in the CNS paired structures that receive otolith afferentation; 2) the same result of interaction (enhancement or attenuation of vestibular responses) can be achieved through both increase or decrease of otolith afferentation; 3) if joint stimulation of semicircular canals and otolith organs induces asymmetry of neuronal activities of paired brain structures that perceive otolith afferentation, then, irrespective of the mechanism of origin of this asymmetry, it is followed by changes of oppositely directed nystagmus of different sign (increase for one nystagmus and decrease for the other). It is concluded that the symmetry of reactions recorded in response to isolated stimulation of semicircular canals (otolith organs) cannot be considered as a reliable criterion of functional symmetry of semicircular canals (otolith organs).  相似文献   

18.
歼击机飞行员垂直半规管功能的检测及其特征   总被引:4,自引:1,他引:4  
目的 建立垂直半规管功能的测量方法 ,对我军部分战斗机飞行员和地面人员的垂直半规管功能进行检测 ,初步确定战斗机飞行员垂直半规管功能的特征。 方法 对 35名男性现役歼击机飞行员和 2 0名地面人员进行检测。在暗室中将受试者在转椅上通过特制头托头后仰 6 0° ,同时头左倾或右倾 4 5°,使两侧前、后垂直半规管分别位于水平面 ,采取 90°/s恒速旋转后急停刺激模式 ,记录旋转后眼震电图 ,分别对两侧前垂直半规管、两侧后垂直半规管受刺激引起的垂直眼震的持续时间、最大慢相速度、慢相速度衰减时间常数及各参数间的两侧不对称比进行计算分析 ,建立垂直半规管功能的测量方法。 结果 同地面人员相比 ,飞行员垂直眼震的最大慢相速度降低 (P <0 0 5 ) ,慢相速度衰减时间常数延长 (P <0 0 5 )。 结论 我军战斗机飞行员垂直眼震功能同地面人员存在一定差别 ,长期飞行对飞行员垂直半规管功能可能产生一定影响。  相似文献   

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目的对垂直半规管功能检查方法及在战斗机飞行员中的应用前景进行综述。资料来源与选择该领域的相关研究论文和综述。资料引用国内外公开发表的论文和综述25篇。资料综合对目前国内外常用的五项垂直半规管功能检查方法及其在军事飞行员中的应用进行分析和总结。结论旋转试验、甩头试验、冷热试验、旋转知觉测试、主动头旋转测试是5项常用的垂直半规管功能检查方法,在战斗机飞行员前庭功能的全面评估中必将发挥越来越重要的作用。  相似文献   

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目的:通过对阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者的心脏超声检查,探讨OSAHS患者心脏结构及其舒张功能的改变情况。方法:分别选择阻塞性睡眠呼吸暂停低通气综合征患者及正常受试者30例,常规行经胸二维M型、频谱及彩色多普勒超声心动图检测,将取样容积置于二尖瓣前瓣环十字交叉处测二尖瓣环收缩期峰值运动速度(sys-tolic peak velocity,SPV),舒张早期峰值运动速度(early diastolic peak velocity,DEV)及舒张晚期峰值运动速度(late diastolicpeak velocity,DLV);左室长轴切面测室间隔肌部上段及左室后壁心肌SPV,DEV及DLV运动速度。结果:OSAHS患者心脏结构均表现为左室心肌呈轻度向心性增厚,TDI二尖瓣环DEV/DLV及左室后壁DEV在OSAHS患者与正常组之间比较差异有统计学意义。结论:OSAHS患者与正常对照组相比表现为左心室心肌增厚,心脏左心室舒张功能受损较重,且随病情的加重而加重。  相似文献   

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