磁共振水成像技术对内耳的成像研究和应用

磁共振水成像技术对内耳的成像研究及应用

研究生：明洁导师：贾文霄教授

摘要

目的：探讨磁共振水成像技术（Magnetic resonance hydrography MRH）的三种后处理方法，即多平面重建（MPR）、最大密度投影（MIP）、容积再现（VR）对内耳显示分别有各自优势，为不同内耳原因导致的感音神经性耳聋（SNHL）选择简单、合理、有效的扫描序列和最佳后处理方法，为临床无创评估内耳病变及诊断治疗提供客观有效的影像学依据。方法：对80例无听力障碍的正常人及45例临床确诊为SNHL的患者行高分辨率三维快速自旋回波T2加权序列（3D TSE T2WI）行横断面扫描，然后行3D TSE T2WI双侧斜矢状面扫描。对45例SNHL患者加扫T1WI，若该序列显示有异常信号则行T1WI扫描。数据采集后传至工作站利用ViewForum后处理软件行MPR、MIP、VR 重建。观察正常内耳及内听道解剖结构的显示情况，并进行测量。应用统计学方法对测量值及不同后处理技术对内耳各解剖结构评分，分别行组间及不同后处理方法间的差异性检验。结果：（1）正常志愿者组80例160耳均能清晰地显示耳蜗前庭神经、面神经、蜗神经及内耳膜迷路的细微解剖结构。（2）VR、MIP测量前、水平、后半规管最大径及管径，蜗管管径及最大径差异有统计学意义；VR、MIP图像质量的差异有统计学意义；VR、MIP、MPR显示膜迷路诸结构及神经的能力的差异具有统计学意义；（3）45例病人中MRI内耳发现有9例异常（阳性率20%），共7种病变，其中儿童（小于14岁）以先天性异常-前庭导水管扩大（3例）最常见。结论：（1）内听道及膜迷路的细微结构可利用磁共振内耳水成像技术得以立体而直观的显示，具有其他方法不可替代的作用；（2）MRH对SNHL病因的诊断有很好的指导作用，是有效的影像学检查方法；（3）在多种内耳水成像技术的后处理方法中，MPR在显示神经方面具有优势，VR在观察膜迷路形态方面更具优势，其图像更清晰，与周围结构的毗邻关系显示的更加确切，能对内耳形态是否具有改变进行更有效地评估。

关键词：内耳；磁共振水成像；3D TSE T2WI序列

Imaging Study and Application of inner ear with Magnetic Resonance Hydrography technique

Postgraduate:Ming Jie Supervisor: Prof. Jia Wenxiao

Abstract

Objective: To probe into the advantage and disadvantage of the three kinds of post-processing method of Magnetic resonance hydrography(MRH)technology, i.e. Mutiplanar reformation(MPR), Maximum intensity projection(MIP) and V olume rendering(VR). Thus choose simple reasonable and effective scanning sequence and best post-processing method for different reasons SNHL, to offer the objective imaging basis for clinic non-invasive evaluation of inner ear. Methods: we performed high-resolution three-dimensional turbo spin echo T2 weighted image (3D TSE T2WI) axial scanning with 3D TSE T2WI and then performed bilateral oblique plan sagittal scanning with 3D TSE T2WI to 80 normal adults and 45 clinically suspected SNHL patients of inner ear. Then performed T1WI axial scanning to 45 patients, if we found abnormal in T1WI, we must performed enhanced T1WI scanning to them.After the data acquisition we transmitted them to the workstation for 2 or 3-dimensional reconstruction in MPR, MIP and VR by ViewForum. The ability of MPR, MIP and VR to showing and measuring anatomic structures in inner ear was studied. Results: (1) Subtle anatomical structure of cochleovestibular nerve, facial nerve and inner ear membrane labyrinth could be clearly shown in 160 ears of 80 eases. (2) There were post-procession-related differences in three semicircular canal height and diameter of upper、lateral semicircular canal, VR, MIP image quality difference was statistically significant, the ability of VR、MIP and MPR display the structure of inner and neural is differences and statistically significant; (3) In 45 cases, 9 cases were found to be abnormal by using MRI (positive rate abnalout 20%) . There were 7 kinds of diseases in these cases. Amongthese abnormal cases, a congenital abnormality-large vestibular aqueduct (3 cases) was the most common disease happened in children. Conclusion: (1) MRI can intuitively and three-dimensionally display the