Evaluate lumbar fluid collection. History of CSF leak following microdiscectomy in June 20, 2016. Prior surgical repair on 9/7/2016, lumbar drain placement, as well as epidural blood patch a 9/21/2016. Five lumbar type vertebral bodies are presumed to be present. Vertebral body heights are within normal limits. Alignment is within normal limits. Bone marrow signal is benign. The conus medullaris is normal in position.There are postsurgical changes of discectomy at L5-S1 with a left-sided laminotomy at L5 and a fluid collection extending from the spinal canal, including the subdural and epidural spaces, and extending posteriorly into the left paraspinous and subcutaneous soft tissues. Compared to 9/1/2016, there has been decrease in size of the fluid collection. For example majority of the previously seen small subdural component has resolved although there remains small amount of subdural fluid at the right L4-L5 level. There is a subcutaneous fluid collection component which measures approximately 16 x 23 mm x 21 mm in the AP, transverse, and craniocaudal dimensions, previously 18 x 44 x 41 mm, findings compatible with decrease in size of pseudomeningocele. There is fluid/blood products predominantly along the right L4 to S1 dorsolateral epidural space related to recent blood patch with mild local mass effect on the thecal sac at the right L5 level. Lumbar drainage catheter is noted entering the spinal canal at the L3-L4 level and extending superiorly.Mild L4-L5 disc bulges again seen with dorsal annular fissure. There is otherwise no significant disc disease, spinal canal, or neural foraminal stenosis at any level.
Compared to 9/1/2016, there is decrease in size of pseudomeningocele centered at the left L5-S1 level with residual fluid, changes related to discectomy, and expected changes related to recent epidural blood patch as detailed above.