Wk 8, Case 3 - Review

Patient History
31-year-old female with a history of a clival mass undergoing preoperative evaluation

Findings
MRI brain and orbits:

Evidence of a mildly heterogenous, markedly T2 hyperintense lesion arising from the midline and right paramedian aspect of the dorsum sellae demonstrating mild heterogenous enhancement. This lesion is mildly hyperintense on the FLAIR images and demonstrates restriction of diffusion, bulging posteriorly into the prepontine cistern, posteriorly displacing the basilar artery and indenting the ventral aspect of the pons. Anteriorly, there is destruction of the posterior wall of the sphenoid sinus with enhancing tumor that projects into the sinus lumen. There is involvement of the right posterior and superior portion of the cavernous sinus by this mass with no obvious involvement of the petroclival fissure. There is extension of enhancing tissue into the superior portion of the right Meckel's cave however. The cavernous sinus portion of the lesion appears to enter laterally displacing the 3rd cranial nerve. There is extension of enhancing tissue into the right side of the sella with left anterolateral displacement of the pituitary parenchyma and deviation of the pituitary stalk to the left. A small T2 hyperintense hypoenhancing lesion is present in the anterior portion of the sella in the midline of uncertain etiology. There is mild elevation of the optic chiasm and impression upon the medial aspect of the right temporal lobe. The mass measures approximately 2.8 cm in the craniocaudal dimension, 2 cm in the AP dimension, and approximately 2.9 cm in the transverse dimension.

The brainstem shows no convincing focal abnormality or signal change. Cerebellum and fourth ventricle are within normal limits. Supratentorial brain shows asymmetric size of the lateral ventricles, with minimal deviation of the septum pellucidum to the left. Otherwise, ventricular system is normal with normal appearance of the third ventricle and the temporal horns. No focal signal abnormalities are present within the supratentorial brain. There is no evidence of restricted diffusion in the brain. No evidence of abnormal susceptibility identified on the gradient echo images.

Orbital structures are within normal limits. No abnormality of the orbital segments of the optic nerves. Paranasal sinuses and mastoids are clear.

Impressions
1. Expansile, focally destructive mass arising from the superior portion of the clivus, with a mild erosive change along the superior aspect of the petrous apex with focal bone destruction and extension of tumor into the sphenoid sinus lumen. This T2 hyperintense mildly enhancing lesion demonstrates restricted diffusion and morphology and location are most concerning for a chordoma. There is extension of the tumor into the posterior superior portion of the right cavernous sinus and extension of the tumor into the suprasellar cistern and into the right posterolateral sella.

Findings
CT HEAD: Again seen is a 2.7 cm hypodense mass at the right central skull base involving the superior portion of the clivus and projecting into the suprasellar cistern. Associated destruction of the posterior wall of the sphenoid bone and the right paramedian dorsal sellae. There is a unchanged bony erosion with herniation of soft tissue into the posterior right sphenoid sinus. There is extension of this soft tissue into the prepontine cistern with posterior displacement of the pons, and lateral and superior involvement of the posterior portion of the cavernous sinus as well as the right side of the sella, which is better demonstrated on the MRI study. Associated mass effect on the adjacent temporal lobe and pons, not significantly changed.Again seen is asymmetric size of the lateral ventricles, right greater than left, with minimal deviation of the septum pellucidum to the left, unchanged from prior studies. No extra-axial fluid collections identified. Gray-white matter differentiation appears preserved.Visualized paranasal sinuses, mastoid air cells and orbits are unremarkable.

CTA HEAD: Bilateral ICAs are patent without evidence of focal stenosis. There is no appreciable narrowing of the right cavernous sinus ICA as it passes in the region of the identified mass involving the superior portion of the right cavernous sinus. There is however anterior displacement of the supraclinoid segment of the right internal carotid artery as compared to the posterior oblique course of the left ICA.

The internal carotid bifurcations are within normal limits. The right A1 segment is diminutive compared to the left, but patent. The distal ACAs are otherwise unremarkable bilaterally. Bilateral middle cerebral arteries as well as the bifurcations of the MCAs and sylvian branches are unremarkable bilaterally. The vertebral arteries, basilar artery, and PCAs are patent and without evidence of focal stenosis or aneurysm.

Impressions
1. Expansile focally destructive mass arising from the superior portion of the clivus, better seen on prior MRI, without definite change. This extends anteriorly into the sphenoid sinus to a focal osseous defect, superiorly into the suprasellar cistern, and laterally into the right cavernous sinus as well as into the right posterolateral aspect of the sella. No acute intracranial abnormality identified.

2. Intracranial CTA without evidence of focal stenosis or aneurysm. No significant mass effect upon the cavernous segment of the right internal carotid artery, but the suprasellar component of the mass anteriorly displaces the supraclinoid segment of the right internal carotid artery.