Computed tomography of the intervertebral foramen

Abstract

52 cases with pathologic lesions in the intervertebral foramen, studied with CT, are analyzed. The most frequent lesions are intraforaminal disc herniations. These are characterized by their hyperdensity in comparison to the dural sac (34 of 34 cases) and their broad contact with the intervertebral disc space (31 of 34 cases). Foraminal size and contour are usually normal. In contradistinction to disc herniations, benign tumors often show bone erosion of the pressure-type with enlargement of the foramen. Bone infiltration was seen only in malignant lesions and in the single case of Echinococcosis. Preoperative diagnosis of vascular lesions which present with foraminal enlargement is most important for the choice of the appropriate operative approach. Correct CT diagnosis of such vascular lesions is only possible with dynamic CT.

Surgical cytoreduction for the treatment of non‐lymphoid vertebral and spinal cord neoplasms in cats: retrospective evaluation of 26 cases (1990–2005)

“…Although results of this study demonstrate that the presence of osseous abnormalities on preoperative diagnostic imaging examinations were common in cats with malignant tumours, their presence was not significantly associated with survival. Similar to what has been previously reported in humans, this study suggests that osseous abnormalities are not a diagnostic imaging feature exclusive to malignant vertebral or spinal cord neoplasia, as cats with benign tumours may have evidence of erosion of vertebral bone and enlargement of intervertebral foraminae as a result of pressure‐induced bone resoprtion 17 …”

“…Similar to what has been previously reported in humans, this study suggests that osseous abnormalities are not a diagnostic imaging feature exclusive to malignant vertebral or spinal cord neoplasia, as cats with benign tumours may have evidence of erosion of vertebral bone and enlargement of intervertebral foraminae as a result of pressureinduced bone resoprtion. 17 Causes of death that were directly tumourrelated have also been documented in individual cats with malignant, non-lymphoid vertebral and spinal cord tumours that have been previously reported in the literature. 7,10,11 The causes of death and median survival time (110.5 days) for cats in this study with malignant tumours are similar to previous reports of dogs treated with a variety of therapies for malignant vertebral (median survival 135 days) 2 and spinal (median survival 180 days) 3 tumours and suggest that malignant vertebral and spinal cord tumours are associated with a guarded long-term prognosis in cats as well as dogs.…”

Effects of body position and clinical signs on L7-S1 intervertebral foraminal area and lumbosacral angle in dogs with lumbosacral disease as measured via computed tomography

“…Computed tomography is an established technique for characterizing intervertebral foramina (radicular canals) in humans and dogs. [51][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66] Intervertebral foramina are complex osseous canals that have been classified into 3 functional zones: entrance, middle, and exit. 32,[66][67][68] The entrance zone is located closest to the vertebral canal and is defined as the zone at the medial portion of the L7 vertebral pedicle.…”

Reliability of MRI findings for Symptomatic Extraforaminal Disc Herniation in Lumbar Spine

“…Extraforaminal disc herniations are usually not detected on myelography and are often overlooked on the high-resolution CT or MR images12. The CT features of extraforaminal disc herniation are nonspecific14,18,19. Recently, a detailed evaluation of disc herniation using only CT imaging was determined to be unsuitable, and MR is preferred because it is noninvasive, has high soft-tissue resolution, and multiplanar imaging capabilities20.…”