Status post L4-S1 laminectomy on 3/21/16. A new low back pain with right lower extremity radiation. Suspicion of infection. The examination is limited by patient body habitus and motion.Sagittal alignment is anatomic. Vertebral body heights are further preserved except for suggestion of minimal height loss at L5. There are changes of the recent L4-S1 laminectomies. Extensive inflammatory changes are present in the subcutaneous fat and the paravertebral soft tissues, including a well-circumscribed subcutaneous fluid collection, which measures transaxially 3.7 cm x 2.0 cm and craniocaudally 5.2 cm. There is no definite deep extension of fluid towards the spinal canal. The abnormal signal and enhancement in the paraspinal muscles is asymmetrically more pronounced on the left side and may represent a correlation of postoperative change and/or inflammatory tissue.Posterolateral at L4-L5 which is best seen on image #24 of series #12, there is asymmetrically increased focal T2 signal which may reflect asymmetric distribution of the CSF related to the compression of the thecal sac. At the same level, there is a focus of T1/T2-hyperintensity at the left L5 laminotomy defect and with similar though more poorly defined change in the overlying soft tissue. This may represent proteinaceous fluid or even minimal postoperative blood products but causes no significant mass-effect on the thecal sac. There is central fluid signal intensity within the mildly expanded L5-S1 disc with peripheral contrast enhancement with infiltrative inflammatory changes including the adjacent soft tissue. This is associated with osseous endplate erosion and irregularity with poor delineation of the cortex, most pronounced along the central portion of upper endplate of S1. The immediately subjacent marrow surrounding L5-S1 show hypointense T1/T2 signal, probably reflecting sclerosis suggesting some degree of chronicity. The adjacent marrow in the superior part of L5 vertebral body and the inferior part of minimally S1 segment as well as the upper part of the left greater than right sacral ala show contrast enhancement.There is also extensive inflammatory change involving the epidural space circumferentially from the lower L4 level to the upper S2 level which shows fairly solid contrast enhancement. This moderately narrows the thecal sac at L5-S1. The inflammatory change also extends along the L5 and S1 nerve roots, again greater on the left side. There is also asymmetric inflammatory change and contrast enhancement involving the left L2-L3 neural foramen with loss of the foraminal fat, extending into the adjacent left pedicle and facet, with adjacent epidural fat resulting in minimal mass-effect on the thecal sac. There is also involvement of the adjacent paraspinal soft tissues though no drainable fluid collection. There is also inflammatory change along the anterior-superior aspect of L2 vertebral body but the adjacent disc shows relative desiccation at this time. This L2-L3 involvement may represent cranial extension of the above-described inflammatory/infectious process in the lower lumbar spine through involvement of the prevertebral soft tissues.Otherwise, there is multilevel degenerative change manifested by disc bulges at L2-L3, L3-L4 and L4-L5 along with facet arthropathy and ligamenta flava thickening resulting in multilevel spinal canal stenosis which is severe at L3-L4, moderate at L4-L5, and mild-to-moderate at L2-L3. This is in addition to the moderate spinal canal stenosis at L5-S1 due to the epidural process.
1.The examination is limited by patient body habitus and motion.2.Extensive inflammatory changes at the L5-S1 disc as well as the L4-S1 laminectomy site with involvement of the epidural space, resulting in moderate compression of the thecal sac and involvement of the L5 and S1 nerve roots. This is probably a combination of postoperative change and an ongoing infectious process. The exact details of previous surgery are not available, however. The involved epidural space shows solid contrast enhancement, compatible with phlegmon with persistent L5-S1 discitis/osteomyelitis. Also, there is a superficial fluid collection in the subcutaneous fat at the surgery site which is nonspecific.3.Contrast enhancement in relation to the left L2-L3 neural foramen and adjacent pedicle and facet likely represents additional early osteomyelitis through involvement of the prevertebral soft tissues. Alternatively, this may represent a separate focus of inflammatory/infectious process. A CT scan of the lumbar spine with provide more details regarding osseous structures, specifically regarding cortical integrity. 4.Multilevel degenerative disease as associated with multilevel spinal canal stenosis, most pronounced at L3-L4 where it is severe.Dr. Monther Qandeel discussed the above findings and recommendations with Dr. Javed Khader-Eliyas (from Neurosurgery) over the phone on 4/26/2016 12:33 PM.