Spinal Disorders: Fundamentals of Diagnosis and Treatment Part 26. Spinal disorders are among the most common medical conditions with significant impact on health related quality of life, use of health care resources and socio-economic costs. Spinal surgery is still one of the fastest growing areas in clinical medicine. | Imaging Studies Chapter 9 231 Routinely Used MR Sequences for the Assessment of the Spine Standard T1 weighted W and T2 W spin-echo sequences are the basis of imaging in the spine Fig. 1 . T1 W and T2 W sagittal sequences as well as axial T2 W sequences provide a basis for the MR imaging of all spine regions. Some surgeons and radiologists prefer axial T1 W images which render the dural sac relatively hypointense and the epidural fat hyperintense. In most cases this protocol two sagittal sequences and one axial sequence is sufficient to make all the relevant diagnoses. Standard MR sequences are sufficient for most indications Figure 1. Normal lumbar MR anatomy a b MidsagittalT2 W W weighted and T1 W c parasagittal T1 W and d axial T2W MR imagesofa normal lumbar spine. a b In non-degenerated discs the structure of the disc is homogeneous inT2W images with a bright hyperintense white signal intensity and a normal disc height. c Parasagittal T1 W image through the intervertebral foramen shows lumbar nerve isointense curved arrows point to L3 L4 and S1 nerve roots and hyperintense perineural fat tissue. d Axial T2 W images at the level of the intervertebral disc L5 S1 and e of the pedicles of S1 white arrowheads show nerve roots L5 curved arrows and S1 straight black arrows . Caused by chemical shift artifact the dura can be seen more clearly on the left side while the border between the dural sac and epidural fat on the right is less distinct anteriorly. In a normal facet joint straight white arrows cartilage should be seen as a bright thin line with adjacent darkthin and regular subchondral cortical bone. 232 Section Patient Assessment T2 W images best demonstrate disc degeneration 30 Fig. 2 annular tears 39 Fig. 3 disc herniation 22 Fig. 4 intraspinal tumors Fig. 5 Grade I Normal adolescent disc. The structure of the disc is homogeneous with a bright hyperintense signal intensity of the nucleus and normal disc height. Grade II Normal adult disc. The structure of the
