MENINGIOMAS INVOLVING THE CAVERNOUS SINUS - VALUE OF IMAGING FOR PREDICTING SURGICAL COMPLICATIONS

OBJECTIVES. The purpose of this study was to determine if it is possib le to predict complications of surgery on cavernous sinus meningiomas on the basis of preoperative MR and CT findings. MATERIALS AND METHODS . We retrospectively reviewed the CT, MR, and postoperative clinical f indings in 65 consecutive patients with pathologically proved cavernou s sinus meningiomas who had surgery during the period 1985-1991. Tumor s were categorized on the basis of their relationship to the cavernous carotid artery. The presence of tumor in three anatomic sites (the se lla, the sphenoid sinus, and the orbital apex) was also correlated wit h surgical complications. RESULTS. Category 1 tumors, which do not com pletely encircle the cavernous carotid artery, were dissected without injury, sacrifice, or grafting of the artery in 91% of cases. Category 2 lesions completely encircle the artery but do not narrow its lumen; they could be dissected from the cavernous carotid artery without art erial injury in 61% of cases, but imaging failed to discriminate diffe rences within this group. Category 3 lesions, which completely encircl e and narrow the cavernous carotid artery, are usually difficult to di ssect free from the artery. The categories also correlated with recove ry of extraocular motility; 84% of category 1 lesions compared with on ly 36% of category 2 or 3 lesions will recover to good or excellent ex traocular motility after cavernous sinus surgery. Tumor involvement of the sella, orbital apex, and sphenoid sinus correlated with postopera tive endocrine dysfunction, decreased visual acuity, and CSF leak, res pectively. CONCLUSION. Imaging studies can frequently predict the diff iculty of resecting cavernous sinus meningiomas from the cavernous car otid artery and the likelihood of permanent loss of extraocular motili ty after surgery on these lesions. This information is helpful in appr opriate preoperative planning and in providing information to patients about to undergo such surgery.