 There is now complete visualization of a prominently diffusion restricting infiltrative mass centered in the left parotid gland. The mass again demonstrates prominent T1 hypointensity and heterogeneous superimposed enhancement with overall T2 hyperintensity with respect to adjacent parotid tissue. The most confluent portion of the left parotid level mass measures 3.0 x 3.8 cm on 24/20, by approximately 4.6 cm CC on 13/20. Lobule of the mass extends deep to the anterior margin of the upper left sternocleidomastoid muscle, just caudal to the mastoid tip. The left retromandibular vein is not readily identified. There is asymmetric enhancement posterior to the left mandibular condyle although this could relate to venous engorgement. There is extension of enhancing soft tissue through the expanded left stylomandibular canal, along the course of the mastoid segment facial nerve. A thick cord of enhancement with associated diffusion restriction measuring up to 8 mm in greatest thickness extracranially extends intracranially via the course of the facial nerve.There is suggestion of asymmetric thickening and enhancement as well as mild T2 hyperintense signal along left V3 through the foramen ovale which appears slightly widened. Although this could represent associated asymmetric venous engorgement secondary to the infiltrative process, there is concern for further perineural spread via the left parapharyngeal and masticator spaces. Meckel's cave and trigeminal nerves appear symmetric and unremarkable.There is an adjacent left level 2A lymph node which measures 1.5 cm on 21/30. There is a small amount of fluid in the dependent pharynx presence of endotracheal tube. The visualized left sigmoid sinus demonstrates intrinsic T1 hyperintensity with corresponding lack of normal T2 hypointense flow-void concerning for slow flow or possible thrombosis. The left internal jugular vein extending from the skull base to just below the left neck mass is not well delineated. There is severe left mastoid air cell and middle ear opacification with fluid signal and intrinsic T1 hyperintensity. There is a lobulated homogeneously enhancing mass in the left internal auditory canal with probable extension into the cochlear fossette. The lobulated soft tissue extends to the porus acousticus and into the prepontine cistern, along the cisternal segments of the cranial nerves VII and VIII. Please refer to separately dictated report for recent MRI of the IACs for further details.There is slight asymmetric prominence of the right aspect of the pituitary gland with slight rightward deviation of the infundibulum, which appears minimally prominent in thickness, although grossly this appears similar to prior exams. Mild dolichoectasia of the visualized left internal carotid artery is again noted.There is exaggeration of the normal cervical lordosis, with focal posterior osteophyte disc complex at C5-C6.
1.Improved delineation of extent of infiltrative mass centered in the left parotid gland with extension to the widened left stylomandibular canal, and further intracranial extension along the significantly thickened and abnormal appearing left facial nerve.2.Additional concern for perineural spread of tumor via left V3 through the somewhat widened foramen ovale, although a component of this enhancement could be venous in origin.3.Redemonstration of known intracranial component of tumor in the left internal auditory canal and cisternal left seventh/eighth cranial nerves. Please see separately dictated report for MRI of the IACs the prior day for further details.4.Abnormal signal in the left sigmoid sinus concerning for thrombosis or at least slow flow, with additional nonvisualization of the upper left internal jugular vein due to adjacent mass effect.