MRI Brain (selected images) - post-surgery
Recent vertex bifrontal craniotomy.
Expected post-surgical changes in the overlying subcutaneous soft tissues.
Thin subjacent extraaxial collection measuring upto 4 mm in depth. At the vertex (at the location of previously demonstrated meningioma) there is a parafalcine surgical cavity containing fluid, blood products, and gas locules.
There is haematoma (a potion of which appears intraparenchymal) with surrounding vasogenic oedema in the posterosuperior paramedian right frontal lobe, lateral and inferior to the surgical cavity. Although not directly involved with the haematoma, localised mass effect causes compression of both pre-and post central gyri on the right. In addition, vasogenic oedema surrounding the haematoma extends into both pre-and post central gyri.
There is new T2 and FLAIR hyperintensity in the paramedian left frontal lobe at the left lateral margin of the surgical cavity which was not demonstrated on preoperative imaging. There is corresponding high DWI signal with low ADC value. Blood products in the central cavity (seen is high T1 signal on sagittal sequence) may partially account for abnormal appearance on diffusion weighted imaging, however the lateral component of low ADC appears to lie beyond the extent of blood product, and is therefore felt to represent true diffusion restriction. This involves the precentral gyrus close to the vertex.
Although slightly narrowed by local mass effect at the surgical site, the T2 flow-void in the superior sagittal sinus appears preserved. Superior sagittal sinus appears patent on phase contrast venography and enhances normally following contrast administration.
Changes post resection of parasagittal meningioma.
Partly intraparenchymal haematoma in the right paramedian frontal lobe. Surrounding vasogenic oedema and mass-effect involves both pre-and post central gyri on the right.
New FLAIR hyperintensity with diffusion restriction involving the left precentral gyrus. Adjacent blood products account in part for this appearance, but laterally the diffusion restriction is felt to represent postoperative change/ischaemia.
Superior sagittal sinus is narrowed but patent.