Thoracic disc herniation versus spinal metastases: optimizing diagnosis with magnetic resonance imaging

Magnetic Resonance Imaging of Spinal Metastases

Sixty-six patients with spinal metastatic disease secondary to urological malignancy underwent magnetic resonance imaging. Twenty-eight patients had clinical evidence of spinal cord compression. MRI demonstrated metastatic cord compression in 16 cases, a benign cause in two cases, nerve root involvement in five cases. In seven patients MRI demonstrated spinal metastases which were not visible on plain radiographs and isotope bone scans. Nine patients had metastatic deposits involving the cauda equina and in a further 22 patients spinal metastases were an incidental finding during MRI for staging of the primary tumour. MRI is a sensitive method of imaging spinal metastases and provides a noninvasive means of assessing patients with spinal cord compression.

In Vivo Proton Magnetic Resonance Spectroscopy of Human Spinal Mass Lesions

OBJECTIVE

To observe metabolic differences between spinal tumor and other diseases in human spinal mass lesions, in vivo 1H magnetic resonance spectroscopy (MRS) was attempted to obtain metabolic signals in patients with various spinal mass lesions.

METHODS

1H nuclear magnetic resonance (NMR) spectra were obtained from 14 patients before surgery using a receive-only surface coil on a 1.5 T clinical magnetic resonance imaging (MRI) unit. MRS findings were compared with the histopathologic results from biopsy. In addition, tumor spectra were compared with the spectra of other benign diseases including disc herniation, which can mimic spinal cord tumor. In vitro 1H-NMR spectra were also collected from perchloric acid extracts of some spinal tumors.

RESULTS

Typical water resonance line widths were in the 6- to 10-Hz range, but the metabolic signals observed were sufficiently resolved to be assigned from comparison with the 1H spectra of brain tissue. Choline was detected in all tumor spectra (n = 6) except ependymoma, whereas it was absent in other benign diseases including disc herniation (mimicking spinal cord tumors), dermoid cyst, tuberculosis, and non-multiple sclerosis myelitis. Spectral patterns of meningiomas, schwannomas, metastasis from renal cell carcinoma, and ependymomas in the spinal cord were similar to those of central nervous system (CNS) tumors. It was not possible to observe distinctive metabolic differences between benign diseases owing to relatively larger line broadening of some signals compared with that in CNS tissue.

CONCLUSIONS

It appeared that acquisition of in vivo 1H-NMR signals was possible in human spinal mass lesions on a 1.5 T clinical MRI unit. Detection of choline only in the spinal tumors may indicate that there is some potential in using in vivo 1H-MRS to distinguish spinal tumors from disc herniation mimicking spinal cord tumors, non-multiple sclerosis myelitis, and dermoid cysts. On the basis of our NMR findings, however, it was not possible to distinguish between benign diseases.

Thoracic extruded disc mimicking spinal cord tumor

BACKGROUND CONTEXT

Thoracic disc herniation is a rare condition. Distinguishing between a herniated disc and tumor for a lesion found at the thoracic level can be a diagnostic challenge.

PURPOSE

To describe a case of thoracic disc herniation that mimicked a spinal cord tumor.

STUDY DESIGN/SETTING

Case report and review of the literature.P ATIENT SAMPLE: Case report.

OUTCOME MEASURES

Report of postoperative symptoms.

METHODS/DESCRIPTION

A 54-year-old man was admitted to the hospital with progressively worsening weakness in both lower extremities, increased numbness of both lower extremities, pain radiating into his groin bilaterally and left foot drop. During a recent visit to his family physician, the patient's legs gave out and he collapsed. Physical examination revealed markedly increased tone in both extremities. Magnetic resonance images at T11-12 showed signal abnormality in the anterior extradural space, which extended posterior and inferior to the disc level to the left of midline. An extramedullary lesion found in the posterior spinal canal showed a low signal on T1 image and a high but heterogeneous signal on T2-weighted images. Preoperative diagnosis was neoplasm. A bilateral decompressive laminectomy was performed under operative magnification and ultrasonography. A large extruded disc was found that migrated from the ventral aspect around the thecal sac and into the dorsal aspect, which compressed the sac to the right. The extradural lesion was dissected off the surrounding thecal sac. Postoperatively, the patient underwent rehabilitation and is able to walk with only minimal weakness of both legs.

CONCLUSIONS

Determining the diagnosis for thoracic spinal lesions, either disc herniation or tumor, is a diagnostic challenge.

Thoracic disk herniation: a case report

OBJECTIVE

Thoracic disk herniations are relatively rare events that often mimic other, more serious disorders. This article discusses the case of a patient with thoracic disk herniation who required unusual treatment to aid resolution of her condition.

CLINICAL FEATURES

The patient, who had a complicated history of prior lumbar disk surgery, sustained a fall onto her buttocks and developed low back and bilateral leg pain. Initial suspicion was of reinjury of the L5 disk.

INTERVENTION AND OUTCOME

Light force spinal manipulation, physical therapies, and eventual cosmetic surgery were able to resolve the condition successfully.

CONCLUSIONS

A clinical situation often may require thinking "outside the box" in order for the patient's condition to be resolved. The failure of symptoms to correspond to the suspected condition should increase the suspicion that another problem may be present.

Three-level thoracic disc herniation: case report and review of the literature

A rare case of three-level thoracic disc herniation with associated neurological impairment, including motor, sensor and urinary disturbances, is reported. The diagnosis and localization of the level of cord compression were mainly based on the clinical examination supported by the findings of magnetic resonance imaging and somatosensory evoked potentials. An anterolateral transthoracic approach at the upper-most affected level was selected for removal of all herniated discs, with the use of a surgical microscope; the resected rib was used for intervertebral fusion. An improvement in the patient's subjective and neurological condition was already apparent a few months after the operation, and solid fusion was roentgenographically found at all operated levels. The use of a surgical microscope allows complete removal of the herniated disc while avoiding wide vertebrectomy and associated iatrogenic damage to the spinal cord.