MRI of Thoracic & Lumbar Spine PDF

MRI of thoracic & lumbar spine Dr.Hayder Jasim Taher PhD of Medical Imaging Outline of my presentation Patient preparation and safety. Precautions. Contrast media. A -Positive relaxation agents (T1 agents). B -Negative rel...

MRI of thoracic & lumbar spine Dr.Hayder Jasim Taher PhD of Medical Imaging Outline of my presentation Patient preparation and safety. Precautions. Contrast media. A -Positive relaxation agents (T1 agents). B -Negative relaxation agents (T2 agents). Gadolinium.  Anatomical overview The thoracic spine (often shortened to T-spine) forms the middle part of the vertebral column. It extends from below C7 of the cervical spine to above L1 of the lumbar spine. There are 12 thoracic vertebra, termed T1-T12. The thoracic spine is unique due to its articulation with ribs via costal facets. The ribs restrict the movement of the thoracic spine somewhat. The thoracic spine is otherwise the most mobile of all spinal column segments. Relative to cervical and lumbar vertebrae, thoracic vertebrae have: (fig.1)  Anatomical overview medium-sized, heart shaped vertebral bodies. medium-sized round vertebral canals. prominent transverse processes with costal facets. long spinous processes angulating downwards. (Fig.1) A portion of the thoracic vertebral column.  Indications of thoracic spine MRI 1-Myelopathy. 2-Herniated disc. 3-Primary malignancy. 4-Secondary malignancy. 5-Radiculopathy. 6-Syrinx. 7-Benign tumor. 8-Multiple sclerosis.  MRI procedure (thoracic spine) Patient position: 1-Place the phased array coil on the magnet table and plug the phased array coil port. 2-Position patient supine, and either head or feet first. A feet first position may be preferred by claustrophobic patients. 3-Place arms at the sides or above the head, whichever is most comfortable for the patient. 4-Use accessories such as the knee bolster and blankets to make the patient as comfortable as possible. 5-Place the axial alignment light 2 cm above the xiphoid which is approximately T7. 6-Explicitly instruct the patient not to move during the scan, e.g.: don’t shift hips or move legs. MRI procedure (thoracic spine)  MRI procedure (thoracic spine) Scout slice placement: - 1-Coronal localizer to obtain sagittal slice. -Alignment: Parallel to the long axis of the spinal cord. - Coverage: A-Superior to inferior: Seventh cervical vertebra to first lumbar vertebra. B- Lateral to medial: Vertebral pedicles on each side. C-Posterior to anterior: Spinous processes to prevertebral tissues. -Sagittal slices can be used to demonstrate: - 1-Vertebral alignment. 2-Syrinx. 3-Cord displacement within the canal due to cord herniation or intradural mass. 4-End plate disruption. 5-Herniated disc. 6-  MRI procedure (thoracic spine) 2-Coronal localizer to obtain axial slice -Alignment: Perpendicular to the long axis of the thoracic cord. - Coverage: A-Superior to inferior: As required by the radiologist, covering from the pedicles of one vertebra above and below the vertebrae of interest, e.g. if T8–10 is of interest, scan from the pedicles of T7 to T11. B-Lateral to medial: Intervertebral foramina on each side. C-Posterior to anterior: Spinous processes to prevertebral tissues. -Axial slices can be used to demonstrate the following: 1- Herniated disc. 2-Canal stenosis. 3-Space occupying lesions within the spinal canal. 4-  MRI procedure (thoracic spine) 3-Sagittal localizer to obtain coronal slice - Alignment: Parallel to the long axis of the spinal cord. - Coverage: A-Superior to inferior: Seventh cervical vertebra to the first lumbar vertebra. B-Lateral to medial: Transverse processes on each side. C-Posterior to anterior: Entire vertebral foramen to midway through the vertebral bodies of C7 and L1. -Coronal slices can be used to demonstrate the following: 1-Scoliosis. 2-Space-occupying lesions within MRI procedure (thoracic spine)  Optional sequences: 1-Chemical shift imaging (T1 GRE) (IP) & (OP) (Sagittal plane). -Purpose: Tissue characterization of bone tumor. 2-DWI (Sagittal plane). -Purpose: Evaluation of spinal ischemia.  Lumbar spine: The lumbar spine (often shortened to L- spine) consists of five adjacent vertebrae of the lower vertebral column, in some cases it is possible to find 4 or 6 vertebrae as an anatomical variant. They participate in the lumbar lordosis, a natural curve in the spine, that is convex anteriorly. Articulations of the facet (zygapophyseal) joints permit flexion/extension and abduction movements. Rotation is greatly limited, and may occur only slightly at the lumbosacral joints. (fig.2)  Indications of lumbar spine MRI 1-Disc prolapse with cord or nerve root compression. 2-Syrinx. 3-Discitis. 4-Evaluation of conus in patients with appropriate symptoms. 5-Arachnoiditis.  MRI procedure (lumbar spine) Patient position: 1-Place the phased array coil on the magnet table and plug the phased array coil port. 2- Patient should be in supine-position. 3-A feet-first orientation may be preferred by anxious patients. 4-Adjust the patient so that the anatomy of interest is center over the selected coil. 5-Use accessories such as the knee bolster, to flatten the lumbar curve and bring it closer to the coil, and blankets to make the patient as comfortable as possible.  MRI procedure (lumbar spine) Scout slice placement: - 1-Coronal localizer for sagittal slice - Alignment: Parallel to the long axis of the spinal cord. - Coverage: A-Superior to inferior: Conus to second sacral vertebra. Coverage should include the twelfth thoracic vertebra, even if the conus is below this level. B-Lateral to medial: Vertebral pedicles on each side. C- Posterior to anterior: Spinous processes to prevertebral tissues. - Sagittal slices can be used to demonstrate the following: 1-Vertebral alignment. 2-Canal stenosis. 3-End  MRI procedure (lumbar spine) 2-Sagittal localizer for axial slice Axial block series planned on a sagittal Axial, planned to each  MRI procedure (lumbar spine) -Alignment: Alignment may vary between sites. Two possibilities are available: 1-As a single block: – in plane with the intervertebral discs. 2- Using multiple angles: – aligned individually to each intervertebral disc space. -Coverage: A-Superior to inferior: Pedicle of the third lumbar vertebra to the pedicle of the first sacral segment for a single block, or from pedicle to pedicle for each individual vertebra. B- Lateral to medial: Intervertebral foramina on each side. C- Posterior to anterior: Medial sacral crest to the prevertebral tissues. - Axial slices can be used to demonstrate the following: 1-Space-occupying lesions within the spinal canal. 2-Paravertebral extension of masses into the soft tissue.  MRI procedure (lumbar spine) 3-Sagittal localizer for coronal slice -Alignment: Parallel to the long axis of the cauda equina. Some obliquity will most likely be required to achieve this. - Coverage: A-Superior to inferior: Conus to second sacral vertebra. Coverage should include the twelfth thoracic vertebra, even if the conus is tethered below this level. B-Lateral to medial: Transverse processes on each side. C-Posterior to anterior: Entire vertebral foramen to midway through the vertebral bodies. - Coronal slices can be used to demonstrate the following: 1-Scoliosis. 2- Space-occupying lesions within the cauda equina. MRI procedure (lumbar spine) Thank