CT-3D MERGE fusion imaging improves image quality compared with CT and 3D MERGE in patients with lumbar disc herniation
0
Citation
28
Reference
10
Related Paper
Abstract:
Background CT-routine MRI fusion imaging has recently become available to evaluate spinal anatomy before surgery. Due to the 3-5 mm slice thickness and non-isotropic of routine MRI sequence, the CT-routine MRI fusion imaging is not good. The MRI multiple recalled gradient echo (MERGE) sequence is potentially useful in diagnosis of lumbar degeneration disease due to the better nerve roots visualization, 1 mm slice thickness and its isotropy. Purpose The present study aimed to evaluate the image quality of CT-3D MERGE fusion images compared with CT and 3D MERGE images in patients with lumbar disc herniation. Methods Fifty-nine patients with lumbar disc herniation who underwent both lumbar CT and MRI including 3D-MERGE and routine lumbar MRI sequences were evaluated. All CT, 3D MERGE and CT-3D MERGE fusion images were separately assessed by two radiologists using five-point Likert scoring method based on five aspects: display of bony structure, intervertebral discs, nerve roots, overall anatomical details and image artifacts. Furthermore, two observers documented the sacral slope (SS), L4/5 intervertebral space heights (ISH), width and height of L4/5 intervertebral foramen (FW and FH) on CT and CT-MERGE fusion images. Results There was insufficient evidence to show a difference in bony structure score between CT and CT-3D MERGE fusion images ( p = 0.22), but it was significantly higher than that of MERGE ( p < 0.001). The scores of intervertebral discs and nerve roots between MERGE and fusion images were not statistically different ( p = 0.19 and 0.88), which were higher than CT (all p < 0.001). The overall anatomical detail score of fusion imaging was higher than CT and MERGE ( p < 0.001). No significant difference of image artifacts score was found among CT, MERGE and fusion images ( p = 0.47). There was no significant difference in SS, ISH, FW, FH values between CT and fusion images (all p > 0.05). Conclusion CT-3D MERGE fusion images exhibit superior image quality to both CT and 3D MERGE for the simultaneous observation of bony structures, intervertebral discs, and nerve roots.Keywords:
Merge (version control)
Intervertebral foramen
One hundred lumbar intervertebral foramina from eighteen spines of fresh cadavera were studied to assess the relationship between compression of the nerve root and the height of the intervertebral disc and the morphological characteristics of the intervertebral foramen as determined on cryomicrotome sections. The critical posterior disc height and the critical foraminal height that were associated with entrapment and compression of the nerve root were determined. Significant positive correlations were demonstrated between compression of the nerve root and the posterior disc height, the foraminal height, and the foraminal cross-sectional area for the four intervertebral levels between the second lumbar and first sacral vertebrae. Nerve-root compression was evident in twenty-one of the 100 foramina, in eight of the ten foramina in which the posterior disc height was four millimeters or less, and in four of the five foramina in which the foraminal height was fifteen millimeters or less. These critical dimensions may be indicators of foraminal stenosis in the lumbar spine. However, compression of a spinal nerve root does not always cause sciatica, and the clinical findings must always be taken into account when a diagnosis of stenosis is considered.
Intervertebral foramen
Lumbar Nerve
Foramen
Lateral recess
Intervertebral Disc
Nerve compression syndrome
Cite
Citations (248)
Spinal nerve sheath tumors arise from the spinal nerve root and grow along it. There are two sites at which the growth of a tumor is restricted: the dural aperture for the spinal nerve root and the intervertebral foramen. This article describes the growth pattern of a spinal nerve sheath tumor along the spinal nerve root at various spinal levels.We retrospectively reviewed the records for 149 patients with spinal nerve sheath tumors who were treated between 1980 and 2001. Of these, 176 resected tumors were classified into five groups according to the relationship to the dura mater and/or the intervertebral foramen.Strictly intradural tumors compose 8% of nerve sheath tumors of the first two cervical nerve roots. The percentage of these tumors increased gradually from the high cervical region to the thoracolumbar region, where it was more than 80%. In contrast, the percentage of strictly extradural tumors gradually decreased from the rostral portion to the caudal portion. Similarly, a percentage of tumors extending outside the spinal canal decreased from the rostral portion to the caudal portion. These changes of the growth pattern may be explained by the anatomic features of the spinal nerve roots, which have a longer intradural component at the more caudal portion of the spinal axis.The anatomic relationship of a nerve sheath tumor with the dura mater and the intervertebral foramen varies depending on the level of the tumor. This knowledge may help us to create a strategy for total resection of a nerve sheath tumor.
Intervertebral foramen
Spinal nerve
Nerve sheath tumor
Nerve sheath
Foramen
Cite
Citations (216)
This is an interesting case presentation of cervical intervertebral disc extrusion in a dachshund with acute neck pain and a nerve root signature in the right forelimb. There was no extradural compression of the spinal cord but lateralised extruded intervertebral disc material where the entire amount of disc material was located deep in the intervertebral foramen, leading to compression of the nerve root. The patient did not respond to conservative treatment, and the pain and nerve root sign persisted. A CT scan showed what was assumed to be a lateralised fragment of calcified extruded disc material in the intervertebral foramen. This necessitated a dorsolateral approach to remove the extruded disc material via a haemilaminectomy. The patient responded very well to surgery and made a full recovery.
Intervertebral foramen
Radicular pain
Intervertebral Disc
Foramen
Cite
Citations (0)
Abstract Background: The anatomical distribution of the extraforaminal ligaments in the cervical intervertebral foramina has been well studied. However, detailed descriptions of the biomechanical characteristics of these ligaments are lacking. Methods: The paravertebral muscles were dissected, and the extraforaminal ligaments and nerve roots were identified. The C5 and C7 or C6 and C8 cervical nerve roots on both sides were randomly selected, and a window was opened on the vertebral lamina to expose the posterior spinal nerve root segments. Five needles were placed on the nerve root and the bone structure around the intervertebral foramen; the distal end of the nerve root was then tied with silk thread, and the weights were connected across the pulley. A weight load was gradually applied to the nerve root (50 g/ time, 60 times in total). At the end of the experiment, segments of the extraforaminal ligaments were selectively cut off to compare the changes in nerve root displacement. Results: The displacement of the C5, C6, C7, C8 nerve roots increases with an increasing traction load, and the rate of change of nerve root displacement in the intervertebral foramen is smaller than that in the nerve root on the outside area (p <0.05). Extraforaminal ligaments can absorb part of the pulling load of the nerve root; the C5 nerve root has the largest load range. Conclusions: Cervical extraforaminal ligaments can disperse the tension load on the nerve root and play a role in protecting the nerve root. The protective effect of the C5 nerve root was the strongest, and this may anatomically explain why the C5 nerve roots are less prone to simple avulsion.
Intervertebral foramen
Foramen
Cervical Nerve
Cite
Citations (0)
Ganglioneuromas are benign, slow-growing tumors originating from sympathetic nerves or peripheral nerves, often associated with multiple tumor syndromes. They occasionally occur as spinal lesions and grow within the spinal canal or as paraspinal lesions. In this report, we describe a rare solitary ganglioneuroma arising from the cervical nerve root (C8) within the intervertebral foramen in adults. The tumor could be detected as a mass limited to the neuroforamen at an early stage by MR images. Unilateral microsurgical foraminotomy and en bloc resection of the tumor resulted in disappearance of the symptoms. Microsurgical resection of the relevant nerve root through limited medial foraminotomy at an intricate anatomical region of the cervico-thoracic junction was appropriate in the current case for complete resection of the tumor as well as to prevent postoperative structural weakness that could result in late segmental instability.
Foraminotomy
Intervertebral foramen
Foramen
Cite
Citations (11)
✓ The relationship of the meninges internally to the nerve roots, posterior root ganglion, and spinal nerve, and externally to the wall of the intervertebral foramen, has been investigated. The neural structures and their coverings are not attached to the foramen. Only the fourth, fifth, and sixth cervical spinal nerves have a strong attachment to the vertebral column, and this is to the gutter of the vertebral transverse process. The observations have relevance to any local lesion that may fix, deform, or otherwise affect the nerve and nerve roots to the point of interfering with their function. They may also be important to traction injuries of nerve roots.
Intervertebral foramen
Foramen
Cite
Citations (78)
Eight cervical spines were used to evaluate the relation of the screw tip to the nerve root in the intervertebral foramen. The specimens were divided into two groups: (a) lateral placement without contact with the nerve root, and (b) lateral placement with penetration of the nerve root. Six screws were used for each specimen. After screw placement, oblique radiographs and axial computed tomography (CT) scans were taken. The results on oblique radiographs showed that 23 (95.8%) of 24 screws without contact with the nerve root were found in the upper zone or the junction between the upper and lower zones of the intervertebral foramen. Twenty (83.3%) of 24 screws with penetration of the nerve root were located in the junction between the lower zone of the intervertebral foramen and the pedicle zone. No definite diagnosis of screw penetration of the nerve root could be made on axial CT scans, although scans can show that the screw is violating the foramen. Whether or not a screw violating the intertransverse foramen and affects the nerve root depends on its position on the oblique radiograph. It may be not necessary to remove or change the screw immediately if a longer screw is found in the upper portion of the intervertebral foramen on the oblique view and angled laterally on axial CT scan in a patient without radicular symptoms.
Intervertebral foramen
Foramen
Apical foramen
Cite
Citations (3)
Objective To investigate the anatomic lumbar nerve root localization and to measure the degree of compression induced by silastic tube implantation in rats. Methods Eighteen pure New Zealand rabbits, weighing from 2.5 kg to 3.0 kg, were randomly allocated into 2 groups:group A ( n =6), in which the animals were dissected according to the geometrical principles to localize the lumbar spinal nerve roots, and the length of spinal nerve, the angle to the dura matter, and the anatomical characteristics such as the diameter of the spinal nerve at the external intervertebral foramen and the sagittal area of the foramen were measured; group B ( n =12), from which the extent of compression of intervertebral foramen was measured by using the sectional anatomic techniques after the artificial implantation of a silastic tube was performed. Results The length of lumbar intervertebral canal, the angle and area of intervertebral foramen varied at various lumbar intervertebral spaces; the length of the spinal nerve root was 5.83 ±1.18mm at L 5～6 and 8.94±1.64mm at L 6～7 , its angles to the dura matter were 55.2±11.1° and 29.6± 4.2° , respectively, on condition that the measured sectional area of the silastic tube was 20% of the sagittal area of the intervertebral canal and 50% of the area of the external intervertebral foramen. Conclusion The animal models of spinal nerve root compression established in this experimental study is similar to that seen in clinical settings. It is suggested that high successful intubation rate and slim possibility of injury to the spinal cord can be expected if it is manipulated in the way described above.
Intervertebral foramen
Lumbar Nerve
Silastic
Foramen
Spinal nerve
Intervertebral Disc
Cite
Citations (0)
Abstract Background The anatomical distribution of the extraforaminal ligaments in the cervical intervertebral foramina has been well studied. However, detailed descriptions of the biomechanical characteristics of these ligaments are lacking. Methods The paravertebral muscles were dissected, and the extraforaminal ligaments and nerve roots were identified. The C5 and C7 or C6 and C8 cervical nerve roots on both sides were randomly selected, and a window was opened on the vertebral lamina to expose the posterior spinal nerve root segments. Five needles were placed on the nerve root and the bone structure around the intervertebral foramen; the distal end of the nerve root was then tied with silk thread, and the weights were connected across the pulley. A weight load was gradually applied to the nerve root (50 g/time, 60 times in total). At the end of the experiment, segments of the extraforaminal ligaments were selectively cut off to compare the changes in nerve root displacement. Results The displacement of the C5, C6, C7, and C8 nerve roots increases with an increasing traction load, and the rate of change of nerve root displacement in the intervertebral foramen is smaller than that in the nerve root on the outside area ( p < 0.05). Extraforaminal ligaments can absorb part of the pulling load of the nerve root; the C5 nerve root has the largest load range. Conclusions Cervical extraforaminal ligaments can disperse the tension load on the nerve root and play a role in protecting the nerve root. The protective effect of the C5 nerve root was the strongest, and this may anatomically explain why the C5 nerve roots are less prone to simple avulsion.
Intervertebral foramen
Foramen
Cervical Nerve
Intervertebral disk
Intervertebral Disc
Cite
Citations (4)
Anatomic studies using cadavers showed that three factors are responsible for radicular symptoms. The first is congenital or acquired abnormalities of nerves and nerve roots—the intradural segmental arrangement of rootlets, congenital anomalies of the nerve roots, and the furcal nerve. Another factor is changes of bone and soft tissue around nerves and nerve roots—indentation of nerve roots and extremely transverse courses of nerve roots. The third factor Is a correlation of two other factors—spatial relationship of the nervous tissue to osseous and nonosseous elements of the spinal canal and the intervertebral foramen. In the intervertebral foramen, the nerve root is surrounded by a rather thick membranous structure, an epiradicular sheath, which is responsible for a tubular form obtained in nerve root Infiltration. Anatomic abnormalities can be observed In contrast studies, but the defects revealed do not correspond necessarily with neurologic symptoms. In such cases, nerve root Infiltration Is very useful for a functional diagnosis. The analysis of radicular symptoms with nerve root Infiltration showed that radicular pain and/or claudication are caused mainly by single nerve root involvement, irrespective of the findings obtained by contrast studies. Furthermore, therapeutic effect of nerve root infiltration can be expected in any disease and it can be applied as a final trial of conservative treatment.
Intervertebral foramen
Radicular pain
Infiltration (HVAC)
Lumbar Nerve
Cite
Citations (164)