 There are postoperative findings related to occipital craniotomy and C1 laminectomy for partial resection of a posterior fossa mass with subjacent susceptibility effect compatible with chronic blood products. There is a right parietal approach ventriculostomy catheter that terminates near the foramen of Monro. The ventricles are minimally decreased in size compared to prior exam. The tumor centered in the right cerebellar hemisphere and brainstem with encasement of the basilar artery and right 7th and 8th cranial nerves has increased in size. Indeed, the tumor overall measures 29 x 40 mm, previously 27 x 36 mm. In particular, a T2 hyperintense portion involving the medulla and upper cervical cord measures 28 x 18 mm, previously 28 x 11 mm. There has also been interval development of nodular enhancement throughout the tumor. There is also new thin linear enhancement surrounding the posterior resection margins. There is unchanged tumor extension along the cisternal portion of the right trigeminal nerve and into Meckel cave. A partially imaged syrinx within the upper cervical cord is slightly decreased in size. There is no evidence of acute infarct. The major cerebral flow voids are intact. The skull and scalp soft tissues are unchanged.
Interval increase in size and enhancement of the residual posterior fossa pilocytic astrocytoma compatible with tumor progression. I personally reviewed the Images and/or procedure with the Resident/Fellow and agree with this report.