多层CT对先天性内耳畸形的诊断价值

Diagnostic Significance of Multidetector Computed Tomography in Congenital Inner Ear Malformations

目的:探讨多层CT(MDCT)对先天性内耳畸形的诊断价值。材料和方法:对50例感音神经性耳聋(SNHL)患者行MDCT螺旋扫描,原始数据采集完后,按层厚0.625mm,重建间隔0.3mm,单侧FOV9.6cm放大重建,再传至工作站行多平面重建(MPR)并利用最小密度投影(MinIP)、容积漫游(VR)及其叠加技术等后处理方法观察内耳结构。结果:50例感音神经性耳聋患者中有20例37耳先天性内耳畸形,其中耳蜗未发育1耳、共同腔畸形1耳、不完全分隔Ⅰ型1耳、不完全分隔Ⅱ型即Mondini畸形8耳、前庭和半规管畸形22耳、前庭导水管扩大20耳、内耳道畸形8耳,伴内耳道底发育不全3耳、外耳道骨性闭锁2耳、面神经管异常4耳、前庭窗闭锁2耳、蜗窗闭锁1耳。结论:MDCT螺旋扫描结合后处理技术能清楚显示先天性内耳畸形的部位和程度并明确其分类,为电子耳蜗的植入提供依据。

Purpose： To evaluate the feasibility and usability of multidetector computed tomography （MDCT） in congenital inner ear malformations. Materials and Methods： Fifty patients with sensorineural hearing loss （SNHL） were examined by MDCT. The axial images of each ear were reconstructed with a field of view of 9.6cm. Then the reconstructed data was sent to workstation and done with multi - planar reformation （MPR） , minimum intensity projection（minIP） and volume rendering （VR） . Results： There are 20 patients （37 ears） with congenital inner ear malformations among 50 patients examined by MDCT. The malformations were cochlear aplasia（1 ear）, common cavity deformity（1 ear）, incomplete partition Ⅰ（1 ear）, incomplete partition Ⅱ（Mondini deformity, 8 ears）, vestibular and semicircular canal malformations（22 ears）,vestibular aqueduct dilate（20 ears） and internal auditory canal malformations（7 ears）. Accompanying hypoplasia internal auditory canal bottom（3 ears）, congenital aural atresia（2 ears）, facial nerve canal anomaly （3 ears）, fenestra vestibule ossification（2 ears） and fenestra cochlear ossification（1 ear）. Conclusion： MDCT allows a comprehensively assessing of various congenital inner ear malformations through high quality MPR, minIP and VR reconstructions which show the site and degree of the malformations clearly. It is very useful to the cochlear implantation.