 Again seen are postoperative changes of suboccipital decompressive craniectomy and C1 laminectomy with resection of small meningioma at the C1-C2 level. Compared to postoperative study from 4/1/2015, there is significant increase in fluid collection involving the suboccipital soft tissues extending to the lower C2 level and measuring approximately 2.6 x 3.6 x 3.6 cm in the AP, transverse, and craniocaudal dimensions, likely representing a pseudomeningocele.The expansile mass involving the medulla and upper cervical cord appears similar in size and configuration. The other known intracranial masses also are not significantly changed including a left cavernous sinus meningioma which extends slightly into the suprasellar cistern and bilateral vestibular schwannomas. Evaluation of the orbits again demonstrates an enhancing mass in the left orbit extending from the orbital apex to just posterior to the globe likely representing an optic nerve sheath meningioma. No abnormal signal within the optic nerve is demonstrated. No significant change in diffuse thickening, T2 hyperintensity and enhancement involving the left upper eyelid.No evidence of acute ischemia or hemorrhage. No new mass effect. No hydrocephalus. There is a small left maxillary sinus mucosal retention cyst.
1. Evolution of postsurgical changes of suboccipital decompression and resection of small C1-C2 meningioma. Interval increase in size of fluid collection in the surgical bed is noted which likely represents a pseudomeningocele.2. Evaluation of the orbits demonstrates no appreciable change in size of left orbital mass which likely represents an optic nerve sheath meningioma when compared to most recent study. There is mild enlargement when compared to more remote study dating back to 6/15/2012. There appears to be mild compression of the left optic nerve. 3. Stigmata of neurofibromatosis type 2 with additional masses including a cervicomedullary ependymoma, left cavernous sinus meningioma, and bilateral vestibular schwannomas which are not significantly changed. 