64层螺旋CT对指导儿童人工耳蜗植入术的临床意义

Clinical significance of 64-slice spiral CT for guiding the artificial cochlea implant surgery in children

目的探讨64层螺旋CT对面神经隐窝径路解剖通道术前影像学评估在儿童人工耳蜗植入术中的临床价值。方法对49例双耳重度感音性耳聋拟行人工耳蜗植入术患儿行64层螺旋CT容积扫描,对外耳、中耳、内耳解剖结构行MPR及VR立体重建,模拟显示面神经隐窝手术路径,分别测量面神经管垂直段距外耳道后壁及面隐窝底距面神经管的距离。结果MPR清晰显示听小骨长轴,半规管、前庭、前庭窗、耳蜗、蜗窗和内听道的骨性解剖结构;MPR图像可同层显示面神经管的鼓室段和垂直段;VR三维立体图像直观显示半规管、前庭、前庭窗、耳蜗、蜗窗、面神经、面神经隐窝和内听道的膜性立体图像。在MPR图像上面神经管垂直段距外耳道后壁的平均距离左、右侧分别为4.46mm、4.53mm;面隐窝底距面神经管的平均距离左、右侧分别为1.02mm、1.03mm。结论64层螺旋CT扫描可清晰显示人工耳蜗植入术面神经隐窝径路重要解剖学标志,面神经隐窝周围解剖结构测量结果可为临床手术提供重要参考数据,对人工耳蜗植入术具有极佳的临床指导价值。

Objective To determine the clinical significance of 64-slice spiral CT for guiding the artificial cochlea implant surgery in children. Methods Forty-nine pediatric patients with severy sensory hearing loss and to be a great need for artificial cochlea implant underwent 64-slice spiral CT volume scans. The external, middle and inner ears were stereoscopically reconstructed by using multiplanar reconstruction （MPR） and volume rendering technique （VRT）. In order to simulate the facial recess operation passage, the distance between perpendicular segment of aquaeductus fallopii and posterior wall of meatus acusticus externus and the distance between facial crypt bottom and aquaeductus fallopii were separately measured. Results MPR could clearly show the skeletal anatomy structures of auditory ossicle long axis, semicircular canal, vestibule, fenestra vestibule, cochlea, fenestra cochleae, and meatus acusticus interuus. MPR images could also show the tympanic segment and perpendicular segment of aquaeductus fallopii on the same slice. VR images could intuitively show the stereoscopic membrane structures of semicircular canal, vestibule, fenestra vestibule, cochlea, fenestra cochleae, facial nerve, facial recess, and meatus acusticus internus. On MPR images, the left and right average distances between perpendicular segment of aquaeductus fallopii and posterior wall of meatus acusticus extcrnus were 4.46 mm and 4.53 mm, respectively; the left and right average distance between facial crypt bottom and aquaeductus fallopii were 1.02 mm and 1.03 mm, respectively. Conclusion 64-slice spiral CT scans can clearly show the anatomic details of facial recess passage during artificial cochlear implant surgery, while the measurements of facial recess anatomy structures can provide important reference data for successfully complete the operation.