CT影像中筛前动脉与颅底的关系及在鼻窦炎手术中的意义

目的 通过CT影像探讨筛前动脉（AEA）与颅底的解剖关系及其在鼻窦炎手术中的意义。方法 回顾性研究2017年1月～2017年8月共52例鼻窦炎患者，所有患者均行鼻窦CT扫描及重建，测量AEA与颅底的距离并分型，测量AEA至额嘴的距离，并研究其与AEA悬空的关系。记录眶上筛房（SOEC）的发生率并以卡方检验分析SOEC与AEA悬空的关系，测量筛板外侧板的深度并进行Keros分型，以 Spearman 相关系数分析Keros分型与AEA悬空的关系。结果 AEA在CT图像中辨别率为100%， Ⅰ型为AEA嵌于颅骨内，占 42.3%（44/104），Ⅱ型为AEA紧贴颅底，占18.3%（19/104），Ⅲ型为AEA悬空于筛窦内，占39.4%（41/104），即AEA的悬空率为39.4%，至颅底的平均距离为（3.8±1.5）mm。AEA至额嘴平均距离（14.1±2.2）mm，其距离在AEA悬空与非悬空组中差异无统计学意义（t=0.740，P>0.05）。在Keros分型中，Ⅰ型占51.9%（54/104），Ⅱ型占37.5%（39/104），Ⅲ型占10.6%（11/104）。Keros分型与AEA发生悬空之间的Spearman相关系数为0.505（P<0.001)，为中度正相关。SOEC发生率为17.3%（17/104），有SOEC的患者与无SOEC的患者的AEA悬空发生率差异存在统计学意义（χ2=4.3287，P<0.05）。结论 当SOEC存在或Keros分型级别较高时，AEA的悬空率明显升高，术前进行CT影像学检查可以识别颅底解剖情况，明确AEA与颅底的位置关系，进而降低术中AEA的损伤风险。

Relationship between the anterior ethmoid artery and skull base in CT images and its significance in rhinosinusitis surgery#br#

Objective To investigate the anatomical relationship between the anterior ethmoid artery (AEA) and skull base and its significance in rhinosinusitis surgery.Methods A retrospective study was conducted in 52 patients with sinusitis from January 2017 to August 2017. All patients underwent CT scan and the images were reconstructed. The distance between AEA and the skull base was measured and AEAs were classified. The distance from the AEA to the frontal beak was measured and its relationship with the AEA suspension was studied. The prevalence of supraorbital ethmoid cell (SOEC) was recorded the relationship between SOEC and AEA suspension was analyzed by Chi-square test. The depth of lateral lamella of the cribriform plate was measured and the Keros classification was used to classify the sinuses. Spearman’s rank correlation coefficient was used to analyze the relationship between Keros classification and AEA suspension. Results The recognition rate of AEA in CT images was 100%. Type Ⅰ AEA was embedded in the skull, accounting for 42.3% (44/104). Type Ⅱ AEA protruded at the skull base, accounting for 18.3% (19/104). Type Ⅲ AEA was suspended in the ethmoid sinus, accounting for 39.4% (41/104), that is, the AEA suspension rate was 39.4%. The average distance to the skull base was （3.8 ± 1.5） mm. The average distance from AEA to beak was (14.1 ± 2.2) mm, and the difference of the distance in the AEA suspended and non-suspended groups was not statistically significant (t=0.740, P>0.05). In the Keros classification, type Ⅰ accounted for 51.9% (54/104), type Ⅱ for 37.5% (39/104), and type Ⅲ for 10.6% (11/104). The spearman correlation coefficient between Keros classification and AEA suspension was 0.505 (P<0.001), which meaned they were moderately positively related. The prevalence of SOEC was 17.3% (17/104). There was a statistically significant difference of AEA suspension rate between patients with SOEC and patients without SOEC(χ2=4.287, P<0.05).Conclusion When SOEC is present or the level of Keros classification is high, the suspension rate of AEA increased significantly. Preoperative CT imaging can identify the anatomy of the skull base, and clarify the positional relationship between AEA and the skull base, and then reduce the risk of AEA injury during surgery.