额窦引流通道和相关结构的多层螺旋CT评价

Frontal Sinus Drainage Pathway and Associated Nasal Structures:MDCT Evaluation

目的：运用多排螺旋CT多层面重组（MPR）技术评价额窦引流通道（FSDP），为前组鼻副窦病变的诊断和鼻内窥镜手术提供实用的影像学信息。方法：回顾分析2008年8～10月在华西医院行鼻部检查50例患者的CT图像资料，其中男24例，女26例，年龄16～62岁，平均37岁。所有病例均行薄层螺旋CT高分辨扫描，扫描平面从硬腭至额窦上缘，准直0．75～1mm。冠状和平行于筛漏斗方向斜矢状重建，层厚及层距均为1mm。结果：斜矢状MPR上，共90侧（90．0％）FSDP由上、下两部构成。上部较宽，呈锥形68侧（75．6％），不规则形15侧（16．7％），卵圆形7侧（7．8％）；下部窄细，为筛漏斗者36侧（40．0％），中鼻道者53侧（58．9％）。10侧（10．0％）不能分辨FDSP上下两部。冠状MPR上，共见钩突99侧，1侧缺如。钩突附于颅底35侧（35．4％），筛漏斗为FSDP下部；附于筛骨纸板63侧（63．6％），中鼻道为FSDP下部；附于中鼻甲1侧（1．0％），筛漏斗为FSDP下部。钩突气化3侧，其中1侧伴中鼻道变窄。筛泡增大32侧（32．0％），其中8侧（25．0％）伴有筛漏斗和半月裂变窄。双侧钩突附着部位相同者41例（82．0％），不同者8例（16．0％）。结论：多排螺旋CT能良好显示FSDP的结构和形态，为该部位病变的临床诊断和术前计划制定提供有价值的解剖信息。

Objective： To evaluate frontal sinus drainage pathway （FSDP） using muti-detector CT （MDCT）, so as to offer useful imaging information for the diagnosis of the disorders of anterior paranasal sinuses and preoperative scheme of functional endoscopic surgery. Methods： Paranasal sinus CT of 50 subjects, including 24 males and 26 females, with age ranged 16 62 years and mean age of 37, examed in our hospital from August to October 2008, were analyzed retrospectively. All subjects were scanned by 16 row MDCT using high resolution technique, with 0.75-1 mm collimation and level range from hard palatine to superior margin of frontal sinus. The coronal, and oblique sagittal multi-planar reconstruction （MPR） in parallel with ethmoidal infundibulum, with 1 mm slice width, were obtained at post processing workstation. Results： The oblique sagittal CT demonstrated that FSDPs in 90 sides were composed of superior and inferior portions. The superior portions had wider space and variable configuration, which appeared as pyramidal or triangle shape in 68 sides （75.6%）, anomalous in 15 sides （16.7%）, oval in 7 sides （7.8%）. The inferior portions were narrow grooves, including ethmoidal infundibulum in 36 sides （40.0%） and middle nasal meatus in 53 sides （58.9%）. Both superior and inferior portions of FSDP were not identified in 10 sides due to excess pneumatization of agger nasi cells and anterior ethmoidal cells. On coronal MPR, uncinate processes in 99 sides were displayed, and its absence only in one side was found. Variable positions attached by anteriosuperior uncinate processes, including the skull base in 35 sides （35.4%） and middle turbinate in 1 side （1% ）, which determined infundibulum as inferior portion of FSDP and the lamina papyracea in 63 sides （63.6 %）, which determined middle meatus as inferior portion of FSDP, were observed. Three pneumatized uncinate processes, among them one associated with stenosis of middle meatus, were found. Enlarged ethmoidal bulla in 32 sides （32.0%）, including associated stenosis of ethmoidal infundibulum and hiatus semilunaris in 8 sides （25.0%）, were demonstrated. In this series, 41 cases （82.0%） with same position and 8 cases （16%） with different position attached by uncinate process in bilateral sides were found. Conclusion： With perfect demonstration of the form and configuration of FSDP, MDCT can supply valuable anatomical information for clinical diagnosis of the disorders in this region and preoperatitve scheme of functional endoscopic surgery.