 Postoperative changes are present from interval suboccipital craniotomy with resection of the posterior C1 arch. A postoperative extradural fluid collection is present within the overlying soft tissues measuring 3.3 cm AP x 6.8 cm craniocaudal x 2.67 m transverse, which does not exert mass effect upon the dura. A reconstructed CSF space is now present posterior to the cerebellar tonsils which retain a pointed configuration. Sagittal, thin section, high-resolution T2 images best demonstrate a thin process extending through the posterior CSF space (for example series 301, image 21/51) with the imaged biphasic CSF flow present only anterior to this. The cervical cord remains normal in signal.There are no fractures or subluxations. The marrow signal is benign, including a stable benign hemangioma within the C6 vertebral body. C2/3: Unremarkable and unchanged.C3/4: Unremarkable and unchanged.C4/5: Mild posterior osteophyte disc complex causing minimal anterior cord flattening. There is no resulting stenosis. These findings are unchanged.C5/6: Mild posterior osteophyte disc complex causing minimal anterior cord flattening. There is no resulting stenosis. These findings are unchanged.C6/7: Unremarkable and unchanged.C7/T1: Unremarkable and unchanged.
Postoperative changes are present from interval suboccipital craniotomy with resection of the posterior C1 arch. A postoperative extradural fluid collection is present within the overlying soft tissues measuring 3.3 cm AP x 6.8 cm craniocaudal x 2.67 m transverse, which does not exert mass effect upon the dura. A reconstructed CSF space is now present posterior to the cerebellar tonsils which retain a pointed configuration. Sagittal, thin section, high-resolution T2 images best demonstrate a thin process extending through the posterior CSF space (for example series 301, image 21/51) with the imaged biphasic CSF flow present only anterior to this.