Clinical question: History of skull base neuroendocrine tumors status post cyber knife treatment 8 -- 2014. Signs and symptoms: Surveillance scan. Pre-and post-enhanced brain MRI:Negative diffusion weighted images.Examination re-demonstrate a very large irregular enhancing mass consistent with patient's known meningioma. The epicenter tumor appears to be in the left cavernous sinus with resultant significant expansion of the sinus by the mass. Medially the tumor extends into the sphenoid sinus and sella and traverses the midline abutting the right cavernous sinus. Posterior there is extensive erosive changes of clivus and dorsum sella with significant bulge of tumor into the prepontine cistern and left superior cerebellopontine angle cistern. There is subtle mass effect, flattening and posterior displacement of the pons and in the basilar artery. The left Meckel's cave is entirely effaced secondary to tumor extension. Laterally there is expansion of cavernous sinus and with loculated appearance of the left lateral margin of tumor highly suspected of extension through the dura Very subtle flair hyperintensity of the displaced left temporal lobe suspicious for small focus of edema. Anteriorly the tumor extends into the posterior left ethmoid air cells as well as left orbital apex. There is decreased caliber and irregularity of the left cavernous carotid secondary to tumor encasement. Inferiorly tumor extends into the left pterygoids and into the enlarged left foramen ovale. Superiorly the tumor extends into the left subfrontal region with subtle elevation of left frontal lobe however without detectable parenchymal edema. There is also extension of tumor into the basal cistern and is in contact with the chiasm without significant mass effect. The tumor however is inseparable from the left optic nerve and encases the left supraclinoid internal carotid..There is also extension of tumor posteriorly along the petroclinoid ligament and with erosive changes of the apex of the left petrous bone. The very irregular shape of tumor makes precise comparison with prior exam difficult. Also prior exam is from an outside institution and without SPGR reformatted thin images which hinders precise comparison. Within this limitation however all measurements of tumor indicate slight interval increased size and extent since prior exam from 3 -- 19 -- 14. The largest transaxial dimensions of tumor are at 51 x 49-mm.Mild to moderate chronic small vessel ischemic stroke are present and without significant change.
1.A large invasive left sided meningioma in the left cavernous sinus, left Meckel's cave, left middle cranial fossa, left posterior ethmoid, sella turcica/basal cistern, prepontine cistern, left upper cerebellopontine angle, left petrous apex, left superior orbital fissure, left orbital apex and the left foramen ovale is again identified. Although very difficult to measure due to the irregular shape of tumor and difference in technique of two studies, all acquired measurements demonstrate subtle interval increased size of tumor since prior outside institution MRI exam from Cook County Hospital dated 3 -- 19 -- 14.2.There is irregularity and decreased caliber of the left cavernous carotid secondary to tumor encasement.3.In the basal cistern the tumor is in contact with the chiasm and inseparable from the left cisternal portion of optic nerve and encases the left supraclinoid internal carotid.4.Diffusion weighted images are negative and mild to moderate findings of chronic non-hemorrhagic small vessel ischemic stroke are noted.