Reason: sp tumor resection and sp SRS, yearly surveillance History: sp tumor resection and sp SRS, yearly surveillance BRAINThere is a redemonstration of a mass at the left cerebellopontine angle cistern also identified on the preoperative exam. It is identified on the diffusion weighted images as well as T1 weighted images. It currently measures 21x11mm sagittal dimensions and 13x19 mm axial dimensions. It previously measured 11x16 mm axial dimensions and has been enlarging over the past few years.The patient is status post left suboccipital craniotomy and left cerebellar hemisphere surgery. There is a fluid collection present at the surgical site within the muscle tissues and which is extracranial and measures 50 x 30 mm axial dimensions and 65 x 29 mm, coronal dimensions and 59 x 29 mm, sagittal dimensions. It is stable. No abnormal enhancing mass lesions are appreciated intracranially. No intracranial hemorrhage is identified. No edema is identified within the brain parenchyma.There is a redemonstration of encephalomalacia involving the left cerebellar hemisphere, as well as some shift of the brainstem and cerebellum towards the right side. There is a mild degree of periventricular and subcortical punctate hyperintense white matter lesions present identified on the FLAIR and T2 images. These are stable since the prior exam. Normal vascular flow voids are present in the distal carotid and vertebral arteries, the basilar artery and the proximal anterior, middle and posterior cerebral arteries as well as the internal cerebral veins and superior sagittal sinus.Incidental note is made of partial empty sella.The visualized portions of the paranasal sinuses are clear. The visualized portions of the mastoid air cells are clear. The visualized portions of the orbits are intact.IACNo abnormal foci of enhancement are appreciated within the internal auditory canals. The cochlea and semicircular canals appear intact. The cochlear nerve can be followed bilaterally tracking into the cochlea within the IAC. The left sided facial and cochlear nerves and the left-sided trigeminal nerves are not readily identified in the posterior fossa but may be retracted due to scarring. The vestibular nerves are not clearly identified.There is redemonstration of a denervation atrophy of the left masticator space musculature.No abnormal enhancing lesions are appreciated at the cerebellopontine angle cisterns nor the internal auditory canals.
1.The patient is status post surgery for removal of a left cerebellar medullary angle cistern and cerebellar pontine angle cistern lesion. There are attendant post surgical changes with an extracranial fluid collection at the craniotomy site.2.There is a small mass present at the left cerebellopontine angle cistern, which continues to enlarge and could represent an epidermoid3.The left vestibular nerves and left trigeminal are not identified. The left facial and cochlear nerves are suspected to be retracted at the left cerebellomedullary angle cistern due to scar tissue along the dura. Denervation atrophy of left masticator space musculature.