Review. Computed tomography of the postoperative lumbar spine

Abstract

Up to 30% of patients who have had lumbar surgery for herniated disk or for spondylolisthesis or spinal stenosis have unsatisfactory results [1 -4]. Postoperative symptoms are often quite similar to the preoperative pain and radicu lopathy, sometimes less intense but often more distressing than before surgery. Once it has been determined that the persistent and recurrent postoperative symptoms are not due to some form of musculoskeletal imbalance or strain, causes to be considered must include changes or compli cations directly related to the surgery or to failure of the surgery to correct the preoperative condition. Indeed, Finne- However, the latter finding is difficult to interpret; is it a recurrent HNP? Is it an extradural scar? Myelography is also generally unrevealing in cases of lateral bony stenosis.As experience with high-resolution CT scanning of the lumbar spine has been increasing, it is becoming apparent that this noninvasive and easily performed study can give considerably more information about the postoperative spine than any of the other current imaging methods. Materials and MethodsAbout 750 patients with previous lumbar laminectomies had CT scanning within a 28 month period. Most of these were postopera tive failed-back syndrome patients, with persistent or recurrent radiculopathy after surgery. A small group of 1 5 patients was scanned within 2 weeks after surgery to evaluate the early appear ance of the postoperative spine. For the most part, these early postoperative patients were asymptomatic at the time.Contrast enhancement studies to attempt distinction between recurrent disk herniation and extradural scar were performed on

Contrast enhanced computed tomography and magnetic resonance imaging in the diagnosis of recurrent disc herniation

“…Postoperative myelography often reveals a defect in the root sleeve at the operated site [22]. The effect may be caused by a recurrent disc herniation, scar tissue or arachnoiditis and the diagnostic value of myelography is insignificant [2,14].…”

Magnetic resonance imaging, computed tomography, and myelography in the diagnosis of recurrent lumbar disc herniation

“…The diagnostic potential probably can be optimized by using additional pulse sequences, smaller slice thickness, and by use of axial slices. Moreover, the use of intravenous contrast enhancement with Gadolinium-DTPA seems promising 11 ' 16. The accuracy of CT to able to differentiate between recurrent disc herniation and scar tissue is reported to be high using contrast enhancement, while the results are more conflicting in unenhanced CT 2' 7, 17 19,21. CT has the advantage over MR!…”

Hematogenous spinal leptomeningeal metastasis: a unique CT enhancement pattern

“…This "pseudomyelogram" pattern was presumably produced by the enhancement of uniform sheets of A large number of hypervascular intraspinal abnormalities are known to enhance on CT with intravenous contrast administration. These include primary and metastatic malignancies in all compartments [1], benign neoplasms (hemangioblastoma, meningioma, hemangioendothelioma) [2] vascular lesions (arteriovenous malformations, hemangioma, fibroangioma) [3], post-lamineetomy hypertrophic scar [4] and arachnoiditis due to a multiplicity of causes [5]. The focal nature of enhancement, in conjunction with the clinical data and myelographic findings, serves to correctly identify the majority of these lesions, however.…”