【作者】 全勇；

【导师】 武乐斌； 巩若箴；

【作者基本信息】 山东大学 ， 影像医学与核医学， 2012， 博士

【摘要】 第一部分CT仿真内窥镜在诊断骨性蜗神经管发育不良中的初步应用研究目的：回顾性评价螺旋状结构消失做为CT仿真内窥镜诊断骨性蜗神经管发育不良的可行性。研究方法：病例组包括14例骨性蜗神经管发育不良患者(平均年龄5.5岁,1-15岁,6男,8女),共20耳。对照组由没有内耳及内听道疾患的50例(平均年龄6.6岁,1-15岁,29男,21女)受试者组成,共100耳。3例病人和9例对照组受试者采用4排多层螺旋CT(MX8000)扫描；11例病人和41例对照组受试者应用16排多层螺旋CT (Somatom Sensation16)或64排多层螺旋CT (Somatom Sensation Cardiac64)扫描。每个受试者仰卧位,头放在中立位置,下颏无旋转,扫描基线为瑞德基线。扫描方向：从上到下；双侧颞骨均扫描。扫描参数如下：MX8000多层螺旋CT：电压120kV；电流150mAs；层厚0.6mm；准直0.5mm；螺距0.875；重建间隔50%；骨算法重建；视野250mm。Sensation16和Sensation64多层螺旋CT：电压120kV；电流150mAs；层厚0.6mm；准直0.6mm；螺距0.5；重建间隔50%；卷积核B70；视野250mm。仿真内窥镜观察骨性蜗神经管采用Fly through技术(Fly Through,3D)。视轴垂直于检查平面,仿真内窥镜视点放在内听道底的前下象限处,指向蜗轴,调整视点位置、视轴方向,如果仿真内窥镜阂值设置如下：下限阈值850-1150,上限阈值3071,在蜗区会出现与螺旋孔列相对应的螺旋状结构。中央管指的是位于横嵴前下方的孔；螺旋状结构指的是位于蜗区的,中央管周围的螺旋状裂隙。阳性结果指螺旋状结构或者中央管的消失；阴性结果指螺旋状结构或者中央管的存在。两个放射科医师独立评价螺旋状结构是否存在。以临床及常规影像诊断结果作为骨性蜗神经管发育不良的诊断金标准。计量资料用Mann-Whitney U检验,计数资料用卡方检验或Fisher确切检验。计算观察者间一致性及CT仿真内窥镜诊断骨性蜗神经管发育不良的敏感性、特异性、准确率、Youden指数。结果：病例组及对照组在年龄(P=0.335)、性别(P=0.314)、左右侧(P=0.683)上无统计学差异。诊断为骨性蜗神经管发育不良的20耳(右11,左9)中,17例未显示螺旋状结构,3例显示螺旋状结构,对照组中均显示螺旋状结构。观察者间有大量一致性(K=0.773)。以螺旋状结构消失做为征象诊断骨性蜗神经管发育不良的敏感性、特异性、准确率、Youden指数分别为85%,100%,98%,0.85。螺旋状结构消失在病例组及对照组之间有明显的统计学差异(P<0.001)。诊断为骨性蜗神经管发育不良的20耳中,5例未显示中央管,对照组中均显示中央管。以中央管消失做为征象诊断骨性蜗神经管发育不良的敏感性、特异性、准确率、Youden指数分别为25%,100%,88%,0.25。中央管消失在病例组及对照组之间有明显的统计学差异。虽然螺旋状结构消失和中央管消失在诊断骨性蜗神经管发育不良有相似的特异度,但是前者有更好的敏感性和准确率。结论：以螺旋状结构消失做为征象诊断骨性蜗神经管发育不良有高的敏感性、特异性、准确率和观察者间一致性,螺旋状结构消失可以作为诊断骨性蜗神经管发育不良的有用征象。第二部分听骨链连接关系层面诊断锤砧复合体中断的临床价值研究目的：评价听骨链连接关系层面诊断锤砧复合体中断的价值。研究方法：收集经手术证实锤砧复合体中断的患者74例(共85耳),男45例,女29例,年龄3-75岁,平均年龄35.7岁,其中11例双耳患病。所有患者均应用16排多层螺旋CT (Somatom Sensation16)扫描。受试者仰卧位,头放在中立位置,下颏无旋转,扫描基线为瑞德基线。横轴位扫描参数：电压120kV；电流350mAs；层厚0.6mm；螺距0.8；重建间隔0.3mm；视野12cm；卷积核B70。听骨链连接关系层面由两个放射科医师独立制作,选择MIP重建,层厚3mm,各解剖结构的定位在轴位及冠状位上确认。听骨链连接关系层面的制作：在轴位图像上参考线平行于锤骨颈和砧磴关节的连线,在冠状位图像上参考线平行于砧骨长脚。放射科医师阅读这些层面,判断下列各段(锤骨头、锤骨颈、锤骨柄、锤砧关节、砧骨短脚、砧骨体、砧骨长脚)是否连续(阴性)或中断(阳性)。同时判断锤砧复合体各组成部分及其中断部位能否在同一个听骨链连接关系层面显示。两个放射科医师独立评价,不一致的协商解决达成一致做为最后的结果。以手术证实的上述各段的连续或中断做为评价的金标准。分类资料用McNemar检验。计算敏感性、特异性、准确率、Youden指数、观察者间一致性。结果：直接轴位图像诊断锤砧复合体中断结果如下：锤骨头(n=21)、锤骨颈(n=20)、锤骨柄(n=23)、锤砧关节(n=7)、砧骨短脚(n=25)、砧骨体(n=35)、砧骨长脚(n=63)。听骨链连接关系层面诊断锤砧复合体中断结果如下：锤骨头(n=20)、锤骨颈(n=19)、锤骨柄(n=26)、锤砧关节(n=10)、砧骨短脚(n=28)、砧骨体(n=34)、砧骨长脚(n=66)。手术证实锤砧复合体中断结果如下：锤骨头(n=22)、锤骨颈(n=21)、锤骨柄(n=27)、锤砧关节(n=11)、砧骨短脚(n=26)、砧骨体(n=35)、砧骨长脚(n=68)。85耳的锤骨头、锤骨颈、锤骨柄、锤砧关节、砧骨体及砧骨长脚及其中断部位均可在同一个听骨链连接关系层面显示。85耳的砧骨短脚及其中断部位需要在多个听骨链连接关系层面上显示。在诊断锤砧复合体中断中听骨链连接关系层面和轴位图像没有统计学差别。听骨链连接关系层面诊断锤砧复合体中断的敏感性：锤骨头90.9%、锤骨颈90.5%,、锤骨柄96.3%、锤砧关节90.9%、砧骨短脚71.4%、砧骨体94.3%、砧骨长脚97.1%；特异度：锤骨头100.0%、锤骨颈100.0%,、锤骨柄100.0%、锤砧关节100.0%、砧骨短脚89.5%、砧骨体98.0%、砧骨长脚100.0%；阴性预测值：锤骨头96.9%、锤骨颈97.0%,、锤骨柄98.3%、锤砧关节98.7%、砧骨短脚86.4%、砧骨体96.1%、砧骨长脚89.5%；Youden指数：锤骨头0.909、锤骨颈0.905、锤骨柄0.963、锤砧关节0.909、砧骨短脚0.609、砧骨体0.923、砧骨长脚0.971。在评价锤骨、锤砧关节、砧骨体、砧骨长脚时Youden指数较高；在评价砧骨短脚时Youden指数较低。评价锤骨时,Youden指数最高的是锤骨柄,次之的是锤骨头,最低的是锤骨颈。评价锤砧关节、砧骨体、砧骨长脚的Youden指数也较高。两个放射医师用听骨链连接关系层面诊断锤砧复合体中断的观察者间一致性如下：锤骨头0.90、锤骨颈0.94、锤骨柄0.95、锤砧关节0.89、砧骨短脚0.75、砧骨体0.85、砧骨长脚0.93。结论：听骨链连接关系层面可以代替直接轴位图像诊断锤砧复合体中断；听骨链连接关系层面可在同一个层面上显示锤砧复合体的大部分结构和病变,有较高的临床价值。更多还原

【Abstract】 Part1Detection of hypoplasia of bony cochlear nerve canal by virtual endoscopy:a pilot studyPurpose:To retrospectively examine the feasibility of computed tomographic (CT) virtual endoscopy (VE) in the evaluation of hypoplasia of bony cochlear nerve canal (BCNC) on the basis of absence of helix-like shape.Material and Methods:Twenty ears in14consecutive patients (mean age5.5years, range1-15years,6boys,8girls) diagnosed with hypoplasia of BCNC were included in this work. One hundred ears in50gender-and age-matched individuals (mean age6.6years, range1-15years,29boys,21girls) without inner ear disease and internal auditory canal (IAC) malformations served as controls. Three patients and9control subjects were scanned with a four-section multi-detector CT scanner (MX8000, Philips Medical Systems). Eleven patients and41control subjects were scanned with a16-section multi-detector CT scanner (Somatom Sensation16; Siemens Medical Solutions) or a64-section multi-detector CT scanner (Somatom Sensation Cardiac64; Siemens Medical Solutions). Each subject’s head was placed in a neutral position, without chin tilt, to approximate the Reid base line. Scanning direction: Cephalocaudal. Both temporal bones were covered by the original scan. Image acquisition and reconstruction parameters for the individual CT scanners were as follows:Parameters for the MX8000were120kV;150mAs;0.6-mm section thickness;0.5-mm detector collimation;0.875beam pitch;50%reconstruction interval and bone algorithm reconstruction kernel;250mm field of view. Parameters for the Sensation16or Sensation64were120kV;150mAs;0.6-mm section thickness;0.6-mm detector collimation;0.5beam pitch;50%reconstruction interval and B70reconstruction kernels;250mm field of view, gvyThe BCNCs of all subjects were endoscopically traversed using3D software program (Fly Through,3D). The view axis was set perpendicular to the examined surface. VE perspective created from the inner margin of the anteroinferior quadrant of the fundus of the IAC to look toward the base of the modiolus, shows the anatomical shape of the BCNC by rotating the viewing point and standing point, or revolving the virtual camera around the viewing axis. If the VE was performed applying low value of850to1150and high value of3071, a helix-like shape appeared in the cochlear area where it corresponded with the tractus spiralis foraminosus. The central canal of the cochlea was defined as the foramen below the anterior part of the transverse crest. Helix-like shape was defined as the spiral fissure in the cochlear area, which runs around the central canal of the cochlea. A positive result on CT VE was defined as absence of helix-like shape or central canal of the cochlea. A negative result on CT VE was defined as presence of helix-like shape or central canal of the cochlea.The presence or absence of helix-like shape was evaluated by two independent reviewers. The value of VE for the diagnosis of hypoplasia of BCNC was assessed with clinical results and routine radiologic evaluation as the reference standard. Quantitative variables between the case group and the control group were tested with the Mann-Whitney U test, and differences in categorical data were tested with the χ2test and Fisher exact tests, if appropriate. Inter-observer agreement was calculated. Sensitivity, specificity, accuracy and the Youden index were selected to test the diagnostic ability of the VE.Results:Of the120ears evaluated in this study,20(11right ears and9left ears) had hypoplasia of BCNC. There was no significant difference with respect to age (P=0.335), sex (P=0.314) and side (P=0.683) between the case and control subjects. Absence of helix-like shape was found in the cochlear area of17of20ears in patients with hypoplasia of BCNC but in none of the control subjects. Three of20(15%) ears of case subjects showed the presence of helix-like shape. Inter-observer agreement was substantial (K=0.773). The diagnostic rates of absence of helix-like shape for hypoplasia of BCNC in terms of sensitivity, specificity, accuracy and the Youden index were85%,100%,98%, and0.85respectively. There were significant differences between the two groups with respect to VE findings for absence of helix-like shape (P<0.001). Five of20(25%) ears of case subjects had absence of the central canal of the cochlea. All of the ears of control subjects had presence of the central canal of the cochlea. The diagnostic rates of absence of the central canal of the cochlea for hypoplasia of BCNC in terms of sensitivity, specificity, accuracy and the Youden index were25%,100%,88%, and0.25, respectively. The comparison of the absence of central canal of the cochlea for the hypoplasia of BCNC between the two groups reached statistical significance. Compared with the absence of central canal of the cochlea, the absence of helix-like shape was found to have better sensitivity and accuracy in the detection of the hypoplasia of BCNC despite the similar specificity (P <0.001).Conclusion:The absence of helix-like shape at VE images offers high sensitivity, specificity and accuracy for the detection of the hypoplasia of BCNC with a substantial interobserver agreement. The absence of helix-like shape at VE images may be used as a potentially useful sign in the diagnosis of hypoplasia of BCNC. Part2Diagnostic Value of Bent-Lever Planes in Detecting Abnormality of the Malleus-Incus ComplexPurpose:To retrospectively investigate the diagnostic value of the bent lever planes in detection of abnormality of malleus-incus complex.Material and Methods:Eighty five ears in74patients (45male patients,29female patients; mean age,35.7years; age range,3-77years) with surgically proved abnormality of malleus-incus complex comprised our study population. Eleven patients had bilateral disease. All of the subjects were scanned with a16-section multi-detector CT scanner (Somatom Sensation16; Siemens Medical Solutions, Forchheim, Germany). The head of each subject was placed in a neutral position, without chin tilt, to approximate the Reid base line. Both temporal bones were covered by the original scan. The transverse images were acquired with a slice thickness of0.6mm, increment of0.3mm (kV,120; mAs,350; pitch,0.8). The raw data were reconstructed by using a bone algorithm and a display field of view of12cm.The bent lever planes for each ear were independently generated at the workstation by two radiologists. The anatomic location and orientation of the structures to be evaluated were confirmed on images in axial and coronal planes of reference. These planes were made in the axial image positioning the reference lines following the line that connected neck of malleus with incudostapedial articulation; in coronal image positioning the reference lines parallel to the long process of incus. For each ear, the acquired data sets were reformatted as S-T-S MIP using a slab thickness of3mm. The radiologists reviewed these planes and were required to comment on the various segments (head of the malleus, neck of the malleus, manubrium of the malleus, incudomalleolar joint, short process of the incus, body of the incus and long process of the incus) of the malleus-incus complex. They were also required to identify whether the various parts of malleus-incus complex and its abnormality can be shown in a single bent lever plane. They made a record independently, then, met with each other to go over every case and come to a consensus evaluation used as the final interpretation. According to this the observers assigned a value of abnormality (positive) or continuity (negative) to the various segments of malleus-incus complex. We took intraoperative findings for ossicular abnormality of various segments of malleus-incus complex as reference standard to evaluate the diagnosis made by the two reviewers. Differences in categorical data were evaluated with the McNemar test. The sensitivity, specificity, negative predictive value, Youden index and interobserver agreement were calculated.Results:The number of direct axial images in detection of abnormality of various segments of malleus-incus complex in85ears were the head of the malleus (n=21), neck of the malleus (n=20), manubrium of the malleus (n=23), incudomalleolar joint (n=7), short process of the incus (n=25), body of the incus (n=35) and long process of the incus (n=63). The number of bent lever planes in detection of abnormality of various segments of malleus-incus complex in85ears were the head of the malleus (n=20), neck of the malleus (n=19), manubrium of the malleus (n=26), incudomalleolar joint (n=10), short process of the incus (n=28), body of the incus (n=34) and long process of the incus (n=66). Intraoperative or pathological findings for lesion location of various segments of malleus-incus complex were head of the malleus (n=22), neck of the malleus (n=21), manubrium of the malleus (n=27), incudomalleolar joint (n=11), short process of the incus (n=26), body of the incus (n=35) and long process of the incus (n=68).The head of the malleus, neck of the malleus, manubrium of the malleus, incudomalleolar joint, body of the incus and long process of the incus of85ears and their abnormalities can be demonstrated in a single bent lever plane. The short process of the incus of85ears and its abnormality must be demonstrated in several bent lever planes. There was no significant difference between bent lever planes and direct axial images in identifying abnormality of the various segments of malleus-incus complex.The sensitivity of bent lever planes in detection of abnormality of various segments (head of the malleus, neck of the malleus, manubrium of the malleus, incudomalleolar joint, short process of the incus, body of the incus and long process of the incus) of malleus-incus complex were90.9%,90.5%,96.3%,90.9%,71.4%,94.3%and97.1%and the specificity were100.0%,100.0%,100.0%,100.0%,89.5%,98.0%and100.0%. The negative predictive value of bent lever planes in detection of abnormality of various segments were96.9%,97.0%,98.3%,98.7%,86.4%,96.1%and89.5%. The Youden index of bent lever planes in detection of abnormality of various segments were0.909,0.905,0,963,0.909,0.609,0.923and0.971. The Youden index of the bent lever planes for the assessment of various segments of malleus-incus complex was high for the components of malleus, incudomalleolar joint, body of incus, long process of incus, less for short process of incus. While studying the malleus, the Youden index of bent lever planes was found to be highest for its manubrium, minimum for its neck and intermediate for its head. High Youden index was achieved with bent lever planes for assessment of incudomalleal joint. In the evaluation of the incus, bent lever planes maintained its high Youden index with regards to evaluation of the body, and long process.The interobserver agreement for the two radiologists in identifying abnormality of the malleus-incus complex with use of bent-lever planes were head of the malleus (k=0.90), neck of the malleus (k=0.94), manubrium of the malleus (k=0.95), incudomalleolar joint (k=0.89), short process of the incus (k=0.75), body of the incus (k=0.85) and long process of the incus (k=0.93).Conclusion:The bent lever planes may replace direct axial images to show discontinuity of malleus-incus complex. The most segments of malleus-incus complex and their abnormality can be demonstrated in a single bent lever plane, which is is intuitive for radiologists.更多还原