磁共振3D-CISS与CT高分辨率成像在电子耳蜗植入前的应用

目的利用中、内耳高分辨C计算机X线断层照相术(computed tomography,CT)扫描及磁共振(magnetic resonance imaging,MRI)高分辨3D-CISS序列成像对拟行人工耳蜗植入术的患者作术前检查,分析、比较两种方法的临床价值。方法选择30例拟行电子耳蜗植入的感音性耳聋患者。行中内耳CT高分辨放大扫描,层厚1mm,层间隔1mm,放大倍数2。磁共振高分辨率三维稳态干扰序列(three dimensional constructive inference insteady state,3D-CISS)扫描(TR12.30ms,TE5.9ms),翻转角70°,层厚0.7mm,无间隔扫描,最大信号强度投影(maximum intensity projection,MIP)内耳重建。比较两种方法提供的信息。结果CT可观察中耳内耳、骨性结构;MRI可显示内耳膜迷路情况及内听道的神经。结论将中、内耳螺旋CT高分辨成像与磁共振高分辨3D-CISS序列其联合应用可为人工耳蜗植入提供更精确可靠的术前信息。     

CT与磁共振图像融合技术对显示正常内耳结构的应用价值

目的 探讨内耳CT与磁共振成像(MRI)图像融合的可行性以及融合图像对正常内耳结构的显示能力.方法 对20例(40耳)双侧内耳及内听道形态正常的感音神经性耳聋患者行多层螺旋CT(MSCT)和MRI扫描,并应用西门子图像融合软件将CT与MRI图像进行配准、融合,然后半定量评价融合图像对正常内耳和内听道结构的显示能力.结果 CT与MRI融合可有9种融合模式,在不同融合模式的图像中CT不反相+MRI反相对骨迷路显示最清晰;CT反相+MRI不反相、CT反相+MRI伪彩对膜迷路显示最清晰、立体感强;CT不反相+MRI反相、CT与MRI均反相对面神经、听神经及蜗神经显示最清晰、最直观、立体感最强;CT不反相+MRI反相、CT反相+MRI不反相、CT伪彩+MRI反相对蜗孔处蜗神经显示最好.结论 CT与MRI图像可以进行精确配准和融合,不同模式融合图像对内耳不同结构的显示清晰度不同.     

正常人内耳MR成像观察及测量研究

目的 :为内耳疾病的定位诊断和显微手术提供正常人内耳的MRI图像及解剖学数据。方法 :选择 33例无任何耳部疾病的正常志愿者 ,采用MRI技术对两侧内耳同时进行三维重建成像 ,观察其形态结构 ,3个半规管和内听道进行测量。结果 :(1) 33例均能满意显示两侧内耳的解剖结构 ,前庭、耳蜗、半规管、内听道显示清晰。 (2 ) 3个半规管内周长、外周长、管腔面积均以后半规管最长 ,上半规管次之 ,外半规管最短。 (3) 3个半规管脚间距以上半规管最大 ,外半规管次之 ,后半规管最小。 (4 ) 3个半规管壶腹端直径均大于 2mm ,外半规管单脚端直径为 (1.37±0 .34)mm ,上、后半规管总脚端直径为 (1.73± 0 .15 )mm。 (5 )内听道四壁中以前壁最长 ,后壁最短。内耳门处上下径小于前后径 ;内听道面积为 35 .4 5mm2 。结论 :利用MRI技术能立体而直观地显示内耳的细微结构。     

先天性内耳发育畸形的高分辨率CT表现

目的探讨先天性内耳畸形的高分辨率CT表现。方法回顾性分析29例(46耳)婴幼儿先天性内耳发育畸形患者的CT表现,所有患者均做多层螺旋高分辨率CT横断面扫描及多平面重建,必要者利用容积再现技术对骨迷路进行三维重建。结果29例先天性内耳发育畸形患者双侧畸形者17例,单侧畸形者12例,内耳发育畸形共计46耳。具体分布如下:(1)Michel型(2耳),(2)耳蜗未发育(6耳),(3)共同腔畸形(5耳),(4)不完全分隔Ⅰ型(5耳),(5)不完全分隔Ⅱ型(传统Mondini型)(17耳),(6)耳蜗形态正常仅前庭及(或)半规管畸形(9耳),(7)单纯内耳道畸形(2耳)。结论高分辨率CT对先天性内耳骨迷路畸形具有重要的诊断价值,并可为人工耳蜗植入术适应证的选择提供重要依据。     

正常成人内耳系统液体容积的磁共振测量与分析

目的 探讨磁共振三维水成像技术在内耳液体容积测量中的应用价值.方法 30例正常成人志愿者均采用GE1.5T磁共振机、8通道头部相控阵线圈,行内耳内听道水成像序列扫描(三维真稳态进动快速成像序列),所采集信号传送至工作站AW4.2进行多平面重建和容积重建,测量耳蜗、前庭-半规管和内听道容积,初步建立其正常值范围,并分别比较耳别、性别及年龄段间有无差异.结果 30例(60耳)正常志愿者的耳蜗、前庭-半规管和内听道容积分别为(101.2±11.1)mm3、(151.5±19.9)mm3和(220.1±58.7) mm3;正常值范围分别为(79.4～123.0)mm3、(112.5～190.5)mm3和(105.0～335.2)mm3;变异系数分别为0.11、0.13和0.27.内耳系统液体容积在耳别、性别及年龄段间差异均无统计学意义(P＞0.05).结论磁共振三维水成像技术可用于活体内耳系统液体容积的测量,为临床上内耳腔道结构的评估及内耳畸形的分类、分型提供影像解剖学依据.     

广西壮、汉族青年面神经在冠状、横断和斜矢状高分辨率CT的定位及临床意义

目的:探讨广西壮、汉族青年面神经各段在不同方位高分辨率CT上的最佳显示层面以及各解剖结构间是否存在民族差异.方法:选取160例壮、汉族青年,用螺旋CT以眦耳线相垂直的直线扫描,获得厚度为0.625 mm的连续CT图像,对图像进行三维重建获得横断和斜矢状位断层图像,选取面神经显示良好的层面进行观测.结果:冠状位能完整显示内耳道段和乳突段,横断位能完整显示内耳道段和迷路段,斜矢状位能完整显示鼓乳段.面神经内耳道段和迷路段长度、膝状神经节到颅后窝、迷路段与鼓室段夹角、内耳道段与迷路段夹角以及鼓室段到外半规管的距离在民族和/或性别间比较差异有统计学意义.结论:面神经内耳道段在冠状位和横断位显示最佳,迷路段在横断位显示最佳,鼓室段在斜矢状位显示最佳,乳突段在冠状位和斜矢状位显示最佳；面神经内耳道段、迷路段和鼓室段与部分周围解剖结构存在民族和/或性别差异,对面神经疾病的影像诊断和手术治疗具有重要意义.     

内耳道的解剖学研究及其临床意义

目的:HTSS为内耳道手术定位提供解剖学依据。方法:对400块颞骨的内耳道及其有关结构进行解剖观察和测量。结果:内耳道与岩大神经管裂孔、弓状隆起等结构有较恒定的位置关系。内耳道底投影点至岩大神经管裂孔的距离,在左右两侧分别为8.85mm、7.95mm;至弓状隆起最高点的距离在左侧为7.89mm,右侧为8.50mm,内耳道上壁长左侧为8.41mm,右侧为8.61mm。结论:岩大神经管裂孔、弓状隆起等颞骨岩部结构是定位内耳道的重要标志。内耳道手术应避免损伤上半规管、耳蜗等结构。     

内耳道底骨性结构、前庭神经与单孔神经骨管的Micro-CT影像解剖学实验研究

目的 探讨内耳道底骨性结构及前庭神经、单孔神经骨管（神经管）的Micro-CT影像解剖学特征。方法 取10%甲醛溶液固定的成人尸头标本6具（颞骨12侧）,其中男性4具、女性2具,具体年龄不详。对12侧颞骨均行Micro-CT扫描,再应用Mimics软件对内耳道底骨性结构及其中的神经管进行三维重建,之后进行影像解剖学观察,并分别测量前庭上神经、前庭下神经、单孔神经管相关解剖学参数。结果 经Micro-CT扫描及三维重建,内耳道底骨性结构及其内穿行的前庭神经和单孔神经管显示清晰。前庭上、下神经及单孔神经的解剖形态、位置及走行存在多种解剖变异以及多交叉分布现象。左右两侧前庭上神经管长度分别为（3.68±0.79）mm和（3.54±1.04）mm,起始处前后径分别为（2.03±0.76）mm和（1.83±0.68）mm、上下径分别为（1.75±0.35）mm和（1.72±0.43）mm,中点处的前后径分别为（0.89±0.19）mm和（1.13±0.29）mm、上下径分别为（1.58±0.26）mm和（1.69±0.58）mm;左右两侧前庭下神经管前后径分别为（0.44±0.07）mm和（0.50±0.29）mm,上下径分别为（0.53±0.11）mm和（0.76±0.38）mm。左右两侧单孔神经管直线长度分别为（3.97±0.68）mm和（3.85±0.69）mm,其内侧段长度分别为（2.54±0.70）mm和（2.26±0.82）mm、外侧段长度分别为（1.82±0.57）mm和（1.99±0.39）mm,内侧段直径分别为（0.67±0.10）mm和（0.66±0.09）mm、外侧段直径分别为（0.47±0.04）mm和（0.51±0.10）mm,内外段交角分别为128.82°±17.23°和127.51°±11.70°。以上各指标测量值侧别间比较,差异均无统计学意义（P值均>0.05）。结论 Micro-CT扫描及三维重建可清晰显示内耳道底骨性结构及前庭神经、单孔神经骨管等结构及其空间位置与走行;前庭神经和单孔神经骨管解剖形态及位置、走行均存在较大变异,但左右侧别间相关解剖学测量结果无差异。     

15例成年国人颞骨内部结构CT解剖学

目的:研究成年国人颞骨内部解剖结构的CT重建图像,为临床耳显微外科及神经外科手术提供解剖学依据。方法:15名健康志愿者应用Picker5000螺旋CT机,平行于听眦线扫描,应用VoxelQ工作站进行多层面重建(multi planar reconstruction,MPR),表面遮盖重建(surface shaded display,SSD)及仿真内窥镜成像(CT virtual endoscopy,CTVE),多角度旋转观察颞骨内部解剖结构。结果:MPR能在不同切面显示耳蜗、半规管、内耳道及面神经管垂直段等结构,显示率为100%;SSD能清晰显示颞骨重要的骨性结构,如内耳门、颈静脉孔等,冠状位切割后的SSD图像能生动地显示锤骨、砧骨的立体形态及空间关系;CTVE可模仿内窥镜从外耳向中耳移动,清晰显示骨性外耳道、鼓室内侧壁及听骨链等结构。结论:MPR可行多方位重建,有助于耳颞部病变的全面了解,是轴位CT良好的补充;SSD、CTVE可准确、立体的观察颞骨内部解剖结构,对临床诊断、手术方案的设计、医学教学等具有指导意义。     

内耳钆造影MRI前庭导水管显影的观察及临床意义

目的 探讨经鼓室内耳钆造影MRI前庭导水管显影率及其临床意义。方法 回顾性分析。纳入2010年2月-2018年1月福建医科大学附属第一医院影像科691例经鼓膜穿刺注射行内耳钆造影MRI的患者造影前后MRI及临床资料,其中男300例、女391例,年龄9~82岁。691例中,531例双侧、160例单侧(共1 222侧)行内耳钆造影。临床表现为眩晕483例、突发性耳聋125例、头晕42例、耳鸣39例、无症状2例,按症状有无进行分组观察。观察患者MRI图像,与造影前相比,造影后前庭导水管区信号升高即判定有显影,否则为无显影;另外,采用目测评分法评价内耳膜迷路是否积水。采用χ²检验分析眩晕组与非眩晕组、突聋组与非突聋组、耳鸣组与非耳鸣组之间前庭导水管显影发生率是否有差异,应用列联相关系数分析前庭导水管显影与膜迷路积水之间的关系。结果 全组691例1 222耳中,26.8%(327/1 222耳)可见膜迷路积水,7.4%(90/1 222耳)可见前庭导水管显影。眩晕组6.0%(56/938耳)可见前庭导水管显影,非眩晕组12.0%(34/284耳)可见显影,差异有统计学意义(χ²=11.509, P＜0.01);突聋组10.2%(19/186耳)可见前庭导水管显影,非突聋组6.9%(71/1 036耳)可见显影,差异无统计学意义(χ²=2.612, P＞0.05);耳鸣组4.0%(6/149耳)可见前庭导水管显影,非耳鸣组7.9%(85/1 073耳)可见显影,差异无统计学意义(χ²=2.880, P＞0.05)。眩晕组30.1%(282/938耳)可见膜迷路积水,非眩晕组15.8%(45/284耳)可见膜迷路积水,差异有统计学意义(χ²=22.488, P＜0.01)。出现膜迷路积水的耳中3.1%(10/327耳)可见前庭导水管显影,无膜迷路积水的耳中8.9%(80/895耳)可见显影,差异有统计学意义(χ²=12.139, P＜0.01);前庭导水管显影与膜迷路积水之间存在负相关关系(r=-0.099, P＜0.01)。结论 鼓室法内耳钆造影MRI图像上,钆对比剂可以进入前庭导水管,显影率约7.4%;骨性前庭导水管内存在外淋巴间隙;内耳钆造影MRI图像上前庭导水管不显影患者存在膜迷路积水的可能性更大,提示有关前庭导水管问题可能是梅尼埃病或眩晕发病机制的重要环节。     

基于内耳体素模型的膜迷路三维可视化

目的探讨基于内耳体素模型三维可视化膜迷路。方法磁共振显微成像颞骨扫描影像数据使用3D Slicer软件进行表面模型体裁剪,将内耳体素模型通过表面绘制和体绘制混合成像三维显示膜迷路。结果通过内耳体素模型可以三维可视化膜迷路,且内耳体素模型文件较表面模型文件容量更小。结论内耳体素模型对于内耳解剖学习和研究有重要意义。     

Comparison of maximum intensity projection and digitally reconstructed radiographic projection for carotid artery stenosis measurement

Digital subtraction angiography is being supplanted by three-dimensional imaging techniques in many clinical applications, leading to extensive use of maximum intensity projection (MIP) images to depict volumetric vascular data. The MIP algorithm produces intensity profiles that are different than conventional angiograms, and can also increase the vessel-to-tissue contrast-to-noise ratio. We evaluated the effect of the MIP algorithm in a clinical application where quantitative vessel measurement is important: internal carotid artery stenosis grading. Three-dimensional computed rotational angiography (CRA) was performed on 26 consecutive symptomatic patients to verify an internal carotid artery stenosis originally found using duplex ultrasound. These volumes of data were visualized using two different postprocessing projection techniques: MIP and digitally reconstructed radiographic (DRR) projection. A DRR is a radiographic image simulating a conventional digitally subtracted angiogram, but it is derived computationally from the same CRA dataset as the MIP. By visualizing a single volume with two different projection techniques, the postprocessing effect of the MIP algorithm is isolated. Vessel measurements were made, according to the NASCET guidelines, and percentage stenosis grades were calculated. The paired t-test was used to determine if the measurement difference between the two techniques was statistically significant. The CRA technique provided an isotropic voxel spacing of 0.38 mm. The MIPs and DRRs had a mean signal-difference-to-noise-ratio of 30:1 and 26:1, respectively. Vessel measurements from MIPs were, on average, 0.17 mm larger than those from DRRs (P < 0.0001). The NASCET-type stenosis grades tended to be underestimated on average by 2.4% with the MIP algorithm, although this was not statistically significant (P=0.09). The mean interobserver variability (standard deviation) of both the MIP and DRR images was 0.35 mm. It was concluded that the MIP algorithm slightly increased the apparent dimensions of the arteries, when applied to these intra-arterial CRA images. This subpixel increase was smaller than both the voxel size and interobserver variability, and was therefore not clinically relevant.     

肝脏IVa、IVb亚段间分界的临床影像解剖学研究

目的通过研究在体肝脏的CT重建图像,确定肝脏左内侧叶IVa、IVb亚段间的分界及走行在两亚段之间的肝静脉属支。方法采用容积再现(volume rendering,VR)和最大密度投影(maximum intensity projection,MIP)两种方法,对49例在体肝脏CT扫描图像进行肝内血管的三维重建,寻找肝脏左内侧叶IVa、IVb两亚段间分界及走行在段间裂内的肝静脉属支及其汇入部位。结果在VR和NIP两种重建图像上,作为两亚段分界标志的肝静脉属支出现率分别为14.29%和87.75%,因此采用MIP法重建出的三维图像对于寻找肝内细小血管分支更适用。该支肝静脉属支的汇入部位可分为以下3种情况:①汇入肝中静脉主干有24例,占55.81%;②汇入肝中静脉左根有16例,占37.21%;③汇入肝左静脉有3例,占6.98%。结论通过CT三维重建图像可以确定肝脏IVa、IVb两亚段间分界,并且走行在该分界位置的肝静脉属支可作为两亚段间的分界标志,结果为临床上涉及肝脏左内侧叶IVa、IVb亚段的肝脏外科手术提供形态学依据。     

Imaging microscopy of the middle and inner ear: Part II: MR microscopy

Anatomic definition of the membranous labyrinth in the clinical setting remains limited despite significant technological advances in magnetic resonance imaging (MRI). Recent developments in ultra-high resolution imaging for use in the research laboratory on small animals and pathologic specimens have given rise to the field of imaging microscopy. We have delineated for the first time the labyrinthine structures in a human temporal bone cadaver specimen using these novel techniques. This approach to the study of the middle and inner ear avoids tissue destruction inherent in histological preparations using standard light microscopy techniques. Part I of this series focused on bony middle and inner ear anatomy with MicrCT. In Part II, we present high-resolution MicroMR images to highlight the utility of this technique in teaching radiologists and otolaryngologists clinically relevant anatomy focusing on the membranous labyrinth. This anatomy can be further enhanced using 3D volume-rendered images. It is hoped that familiarity with these ex vivo anatomic techniques will encourage further developments in the field of high-resolution clinical imaging for patients with temporal bone pathologies.     

Evolutionary changes in the cochlea and labyrinth: Solving the problem of sound transmission to the balance organs of the inner ear

This review article examines the evolutionary adaptations in the vertebrate inner ear that allow selective activation of auditory or vestibular hair cells, although both are housed in the same bony capsule. The problem of separating acoustic stimuli from the vestibular end organs in the inner ear has recently reemerged with the recognition of clinical conditions such as superior canal dehiscence syndrome and enlarged vestibular aqueduct syndrome. In these syndromes, anatomical defects in the otic capsule alter the functional separation of auditory and vestibular stimuli and lead to pathological activation of vestibular reflexes in response to sound. This review demonstrates that while the pars superior of the labyrinth (utricle and semicircular canals) has remained fairly constant throughout evolution, the pars inferior (saccule and other otolith, macular, and auditory end organs) has seen considerable change as many adaptations were made for the development of auditory function. Among these were a relatively rigid membranous labyrinth wall, a variably rigid otic capsule, immersion of the membranous labyrinth in perilymph, a perilymphatic duct to channel acoustic pressure changes away from the vestibular organs, and different operating frequencies for vestibular versus auditory epithelia. Even in normal human ears, acoustic sensitivity of the labyrinth to loud clicks or tones is retained enough to be measured in a standard clinical test, the vestibular-evoked myogenic potential test.     

Optical coherence tomography of the rat cochlea

Optical coherence tomography (OCT) was used to image the internal structure of a rat cochlea (ex vivo). Immediately following sacrifice, the temporal bone of a Sprague-Dawley rat was harvested. Axial OCT cross sectional images (over regions of interest, 1x1 mm-2x8 mm) were obtained with a spatial resolution of 10-15 microm. The osseous borders of the lateral membranous labyrinth overlying the cochlea and the scala vestibuli, media, and tympani, which were well demarcated by the modiolus, Reissner's and the basilar membranes, were clearly identified. OCT can be used to image internal structures in the cochlea without violating the osseous labyrinth using simple surgical exposure of the promontory, and may potentially be used to diagnose inner ear pathology in vivo in both animal and human subjects labyrinth.     

Formation of the Periotic Space During the Early Fetal Period in Humans

The inner ear is a very complicated structure, composed of a bony labyrinth (otic capsule; OC), membranous labyrinth, with a space between them, named the periotic labyrinth or periotic space. We investigated how periotic tissue fluid spaces covered the membranous labyrinth three‐dimensionally, leading to formation of the periotic labyrinth encapsulated in the OC during human fetal development. Digital data sets from magnetic resonance images and phase‐contrast X‐ray tomography images of 24 inner ear organs from 24 human fetuses from the Kyoto Collection (fetuses in trimesters 1 and 2; crown—rump length: 14.4–197 mm) were analyzed. The membranous labyrinth was morphologically differentiated in samples at the end of the embryonic period (Carnegie stage 23), and had grown linearly to more than eight times in size during the observation period. The periotic space was first detected at the 35‐mm samples, around the vestibule and basal turn of the cochlea, which elongated rapidly to the tip of the cochlea and semicircular ducts, successively, and almost covered the membranous labyrinth at the 115‐mm CRL stage or later. In those samples, several ossification centers were detected around the space. This article thus demonstrated that formation of the membranous labyrinth, periotic space (labyrinth), and ossification of the OC occurs successively, according to an intricate timetable. Anat Rec, 301:563–570, 2018. © 2018 Wiley Periodicals, Inc.