CT影像上易误诊为鼻骨骨折的正常结构

The Normal Anatomy of Nasal Bone Easily Misdiagnosed for Nasal Bone Fracture

目的对正常鼻骨及骨缝的CT影像学表现进行观察,探讨易误诊为鼻骨骨折的正常结构,为鼻外伤的CT诊断提供参考信息。资料与方法20名无鼻外伤自愿者,采用Siemens Somatom AR. star螺旋CT横轴位及冠状位扫描,层厚2mm。横轴位扫描以听眦线为基线至鼻尖骨性终末。冠状位扫描其基线与鼻骨前缘平行扫描至鼻尖下部骨性终末。结果横轴位CT表现:鼻骨根部呈"座式电话机手柄"状,鼻骨体部呈"拱桥"状,鼻骨尖部呈"刀尖"状。鼻上颌缝显示20例,鼻骨间缝显示18例,鼻额缝不显示,鼻骨孔显示7例,鼻骨变异1例。冠状位CT表现:鼻骨前部(即鼻背部)呈"鸭嘴"状,鼻骨中部呈"三叉"状,鼻骨尖部呈"刀尖"状。鼻上颌缝显示20例,鼻骨间缝及鼻额缝显示18例,鼻骨孔显示8例,鼻骨变异2例。结论正常鼻骨在CT轴位和冠状位扫描的不同层面各有其特征性表现,鼻骨孔、鼻骨间缝、鼻上颌缝及某些变异均有可能误诊为骨折。

Objective To study normal anatomy of nasal bones and bone sutures and probe bones of nasal region easily misdiagnosed for fractures on CT. Materials and Methods 20 volunteers without trauma of nasal rigion were examined by spiral CT scanning in coronal and axial views. Slice thickness were of 2 mm. Results Appearances on axial CT： the root portion of nasal bone was shaped as the handle of telephone ; the body of nasal bone showed as curved bridge ; the tip of nasal bone appeared as the knife tip. The nasomaxillary suture was visualized in 20 cases, the internasal suture in 18 cases, nasal bone foramen in 7 cases, nasal variation in 1 case, and nasofrontal suture was not visualized. Appearance on coronal CT ： the anterior portion of nasal bone appeared as duck mouth ; the middle portion of the nasal bone appeared as fork with three branches, the tip of nasal bone as knife-tip. The nasomaxillary suture was visualized in 20 cases, the internasal suture and the nasofrontal suture in 18 cases, the nasal bone foramen in 8 cases, nasal variation in 2 cases. Conclusion Normal nasal bone has got its charateristic appearance on the Axial and coronal views. The nasal bone foramen, internasal suture, nasomaxillary suture and some variations might be misdiagnosed for fracture.