垂体腺瘤侵袭海绵窦时颈内动脉的MRI表现

Cavernous Sinus Invasion from Pituitary Adenoma: MRI Findings of Internal Carotid Artery

目的 研究垂体腺瘤对颈内动脉海绵窦段的影响以及垂体腺瘤侵袭海绵窦时颈内动脉的MRI表现。资料与方法 回顾分析 10 3例经病理证实的垂体腺瘤的MRI资料 ,测量两侧颈内动脉距中线距离、横径、被肿瘤包绕程度、颈内动脉间距 ,并与 15 0例非鞍区病变患者颈内动脉的MRI表现相比较。结果 非鞍区病变患者两侧颈内动脉海绵窦段间平均距离为 (17.0± 3.5 )mm ,而垂体腺瘤患者则为 (2 4 .4± 4 .2 )mm。颈内动脉间距与肿瘤横径明显相关 ,而与肿瘤体积的相关性相对不明显。海绵窦是否受侵犯与同侧颈内动脉被包绕范围明显相关 ,而与颈内动脉距中线距离及颈内动脉横径无关。结论 两侧颈内动脉间距仅能反映垂体腺瘤的大小 ,与侵袭性无关。海绵窦是否受侵与颈内动脉的移位、狭窄情况无关 ,而与颈内动脉的包绕程度相关 ,颈内动脉被肿瘤包绕范围 <1/ 3,海绵窦未受侵犯 ;若 >2 / 3,则海绵窦受侵犯。

Objective To study the effect of pituitary adenoma on the cavernous sinus segment of the internal carotid artery (ICA), and to observe MRI manifestations of ICA involvement caused by pituitary adenoma.Materials and Methods MRI materials of 103 cases with pathologically proved pituitary adenoma (study group) were collected. The distance between ICA and midline, the ICA width, the tumor-encasement degree of ICA cavernous segment and the distance between bilateral cavernous segment of IVA were measured. The results were compared with that of 150 cases with non-sellar region lesions (control group). Results The mean distance between bilateral cavernous ICA was 17.0±3.5 mm and 24.4±4.2 mm in the control group and in the study group, respectively. The distance was obviously correlated with tumor's width. Cavernous sinus invasion was well related to the encasement extent of ICA, but not related to the ICA-midline distance and the ICA width.Conclusion The distance between bilateral cavernous ICA only reflects the tumor's size, and is not related with the tumor's invasiveness. The involvement of the cavernous sinus segment shows no relation to ICA displacement or stenosis, but is related to the tumor-encasement degree of cavernous ICA. When the encasement of cavernous ICA by the tumor is over two-thirds, the ICA is certainly invaded. The encasement degree of ICA can be used as an index for judging the cavernous sinus invasion from pituitary adenomas.