13-year-old with history of Chiari malformation status post decompression as well as pituitary microadenoma status post transsphenoidal resection. Follow-up exam. Pituitary: Expected postoperative findings from prior transsphenoidal pituitary resection. There is about 4mm sized non enhancing foci on the right anterior aspect of the pituitary fossa on dynamic pituitary imaging (series 1401, image 22/40). Since the scan parameter especially slice thickness of the delayed coronal and sagittal scan was different (3mm) from that of dynamic scan (2.5mm), it was difficult to determine the nature of the lesion. In particular, it is not clear if the lesion shows no enhancement or enhancement on delayed scan. Especially on delayed post contrast sagittal scan, the lesion appears to be located on the anterior aspect of pituitary fossa which could raise possibility of partial volume artifacts with sphenoid sinus wall. Comparing to prior scan on Jan 8 2015 dynamic MRI scan, the lesion has not been changed in term of MR characteristics and size (series 1401, image 21/40). Constellation of these findings indicate the lesion could suggest partial volume artifacts of sphenoid sinus wall, postoperative scar or changes or less likely residual pituitary lesion. Clinical and laboratory correlation would help the differential diagnosis.There is no focal enhancement or discrete underlying mass lesion to suggest recurrent microadenoma. The infundibulum is intact and not significantly deviated. There is no mass effect on the adjacent structures. The cavernous sinus is intact.Brain: Postoperative findings related to prior suboccipital decompression. There is a stable appearance of the cerebellar tonsils. No evidence of intracranial hemorrhage, mass, or acute infarct. There is stable asymmetry of the lateral ventricles with the right slightly larger than the left. The major cerebral flow voids are intact. CSF flow imaging at the level of the foramen magnum shows robust bidirectional flow along the ventral aspect of the cord. No significant flow is appreciated along the dorsal aspect of the cord, however this may be technical as this region appears widely patent.
1. Postoperative changes from transsphenoidal pituitary resection without evidence of recurrent pituitary mass.2. Non enhancing lesion on the dynamic pituitary imaging on the anterior and slightly right lateral aspect of the pituitary fossa was seen, unchanged since prior scan. 3. Postoperative changes from suboccipital decompression. CSF flow imaging at the level of the foramen magnum shows robust bidirectional flow along the ventral aspect of the cord. No significant flow is appreciated along the dorsal aspect of the cord, however this may be technical as this region appears widely patent.I personally reviewed the Images and/or procedure with the Resident/Fellow and agree with this report.