Value of MRI characteristics of medial wall of cavernous sinus in preoperative assessment of invasive pituitary adenomas

Abstract

Objective To evaluate the value of MRI characteristics of medial wall of cavernous sinus in preoperative assessment of invasive pituitary adenomas,Methods The MRI scans of 39 pituitary adenomas were obtained with a 3.0 T MRI scanner preoperatively.Special attention was given to the integrity of the medial wall of cavernous sinus,Knosp- Steiner grading scales,relationship between tumor and internal carotid artery and possible infiltration of cavernous sinus.Then all the patients received operations,37 cases through transspheniodal approach and 2 transcranial approach.The dura of sellar floor and tumor tissue were obtained intraoperatively to assess the growth pattern of tumor by histologically verified dural invasion and Ki -67 labeling index( Ki -67 LI),respectively.The surgical and pathological findings were compared with the MRI findings.Results The integrity of the medial wall of cavernous sinus were compared with the surgical findings,the positive predictive value (PPV),negative predictive value (NPV),Youden index and the area under ROC curve to infiltration of the medial wall were 75％,100％,0.952,0.976,respectively,demonstrating good diagnostic value on cavernous sinus invasion (CSI).The kappa value was 0.788,0.732,0.611between the integrity of the medial wall of cavernous sinus and Knosp - Steiner grading scale,relationship between tumor and internal carotid artery and possible infiltration of cavernous sinus,respectively,which revealed consistency among them.Accordingly,the integrity of the medial wall of cavernous sinus was related to the dural invasion of sellar floor and the Ki -67 LI.Conclusions The integrity of the medial wall of cavernous sinus on 3.0 T MRI is an important preoperative predictor of CSI,which will guide the resection schedule and a safer and less invasive access to the lesion located in cavernous sinus. Key words: Cavernous sinus; Medial wall; Pituitary adenomas; Invasion; MRI; Dura; Ki -67 labeling index