高分辨率CT扫描图像对后鼓室及其邻近结构的定位

背景:受扫描层面及部分容积效应的影响,高分辨率CT影像学检查很难准确、清晰地观察颞骨内的细微结构,而应用薄层断面与高分辨率CT图像相结合,可精确辨认耳内各微小结构.目的:实验拟解决高分辨率CT扫描图像对后鼓室及其邻近结构的定位方法,为后鼓室及耳科病变的影像变化提供解削学佐证.设计、时间及地点:耳颞区断面标本与CT图像对照观察,实验于2004-07/2007-06在南昌大学医学院断层影像解剖研究室和江西省人民医院影像中心完成.材料:外观无异常的经100 g/L甲醛固定的成人颅脑标本15例(30侧),由南昌大学医学院人体解剖教研室提供;GE Hi-speed Nx/i Sys CT设备由美国通用电器公司提供.方法:以眦耳线为基线,获得M隔为1.00mm,厚度为1.00 mm的CT图像,扫描后的头部标本按原定位截取以耳颞区为中心的组织块并将其制成厚为1.00 mm的连续横断薄层切片.主要观察指标:标本切片与高分辨率CT图像对照,逐一辨识颞骨内砧骨窝、鼓索隆起、茎突隆起、面神经隐窝、鼓室窦、岬小桥、外耳道上棘等结构.结果:砧骨窝深度为(1.494-0.05)mm,至面神经锥曲的距离为(5.67±0.14)mm.后鼓室窦内侧壁至面神经水平部的距离为(3.124±0.15)mm.外耳道上棘至面神经垂直段、鼓索神经、鼓岬的距离分别为(16.73±1.24)mm、(15.87±1.14)mm和(21.84±2.43)mm.结论:高分辨率CT扫描图像结合耳颞区薄层断面标本可对后鼓室内的砧骨窝、鼓索隆起、茎突隆起、面神经隐窝、鼓室窦、岬小桥等结构进行定位.

Localization of the posterior tympanum by using high-resolution CT image

BACKGROUND:Though the high-resolution CT(HRCT)could identify the inner structures of temporal bone.its tiny parts could hardly be observed accurately and clearly by the imaging examinations of auriculotemporal portion,with the influence of scanning layers as well as the partial volume phenomenon.However,it could be easily identified by the combination of thin sections and HRCT images.OBJECTIVE:To introduce a method which could locate the posterior tympanum and its neighboring structures using HRCT images and to provide an anatomical base for the imaging diagnosis and operative treatment on this area.DESIGN,TIME AND SETTING:The observations between the auriculotemporal sections and CT images were finished both in thc Department of Sectional and Imaging Anatomy,Medical College,Nanchang University and the Center of Medical lmageology.Jiangxi Provincial People's Hospital from July 2004 to June 2007.MATERIALS:Fifteen normal adult cadaveric heads(30 sides)which fixed by 100 g/L formaldehyde were scanned,with all the samples provided by the Department of Anatomy,Medical College,Nanchang University.The main equipment was GE Hi-speed Nx/i Sys CT equipment (GE Company,USA).METHODS:Tb obtain CT images of temporal bone(depth 1.00 mm,thickness 1.00 mm),15 normal adult cadaver heads were scanned by CT method taking callthomeatal line(CML)as the baseline.After that,specimens of auriculotemporal portion from temporal bone were taken,decalcified,desiccated and embedded.Sequential sections(thick 1.00 mm)were made.MAIN OUTCOME MEASURES:Comparing sequential sections with CT image,identified respectively the fossa incudis,chorda eminence,styloid eminence,tacial recess,sinus tympanl,ponticulus promontoni,suprameatal spine,etc.RESULTS:The depth of fossa incudas was about(1.49±0.05)mm,the distance from the fossa to pyramid segment of facial nerve was(5.67±0.1 4)mm.The distance from the medial wall of posterior tympanic sinus to the horizontal segment of facial nerve was(3.1 2±0.1 5)mm.The average distance from suprameatal spine to the vertical segment of facial nerve was (16.73±1.24)mm,to chorda tympani nerve(15.87±1.14)mm,to promontory(21.84±2.43)mm.CONCLUSION:Comparing the sectional antomy and CT image of auriculotemporal potion of temporal bone is valuable for the diagnosis and treatment of otopathy.