Clinical question: Follow-up acoustic neuroma status post resection 4/28. Signs and symptoms: None surveillance study. Pre and post enhanced MRI of the IACs:The examination redemonstrates stable irregular T2 hypointense enhancing lesion within the left IAC fairly similar to prior exam. Additionally there is a thin linear dural based enhancement along the dorsal aspect of the left petrous bone at the surgical site. None of the lesions is highly suggestive of tumor and likely representing postsurgical scarring and less likely possibility of residual tumor cannot be entirely excluded. Further follow-up is recommended.There is widening of left cerebellopontine angle cistern secondary to prior surgery and long standing mass effect secondary to previously removed large tumor at this site.Focus of T2 and FLAIR hyperintensity involving the left brachium pontis reaching the left lateral aspect of the pons and without enhancement similar to prior exam and representing gliosis.Pre and post enhanced brain MRI:No diffusion-weighted abnormality.Examination demonstrates punctate size foci of nonspecific FLAIR hyperintensity in the subcortical and periventricular white matter of bilateral cerebral hemispheres and minimally within the left basal ganglia, left thalamus and pons without hemorrhagic changes or abnormal enhancement. Considering patient's stated age of 72 findings are likely representing chronic microvascular ischemic changes of mild degree.Focus of FLAIR hyperintensity in the left brachium pontis with evidence parenchymal volume loss consistent with a focus of encephalomalacia and gliosis as detailed on MRI of IACs. Unremarkable post enhanced brain MRI otherwiseExpected chronic postoperative changes of left suboccipital craniectomy for removal of tumor. Unremarkable calvarium, orbits and paranasal sinuses. There is however evidence of opacification of a single left posterior ethmoid air cell similar to prior exams.
1.Pre- and post enhanced MRI of IACs demonstrate persistent irregular enhancement within the left internal auditory canal and with a thin dural based enhancement in the left cerebellopontine angle suggestive of post surgical changes/scarring. Less likely possibility of residual tumor within the left IAC cannot be entirely excluded and further follow-up is needed.2.Pre- and post enhanced brain MRI demonstrate no evidence of acute intracranial process. Findings suggestive of mild chronic nonhemorrhagic small vessel ischemic strokes and expected postoperative changes of left suboccipital small craniectomy defect.