- Comparison of MR Imaging Findings between Extraligamentous and Subligamentous Disk Herniations in the Lumbar Spine
Extra- and subligamentous lumbar disk herniations are treated differently. These authors utilized 10 criteria in an attempt to establish the exact location of disk herniations with respect to the posterior longitudinal ligament. Extraligamentous herniations showed: 1) spinal canal compromise of more than half its diameter, 2) internal signal difference in the disk, 3) ill-defined disk margins, 4) disruption of the continuous low-signal-intensity line covering the disk, and 5) presence of an internal dark line in the herniated disk. When combined these 5 yield sensitivity, specificity, accuracy, and an odds ratio of 77.3%, 74.5%, 76.1%, and 9.93, respectively.
- Diffusion Tensor Imaging Correlates with the Clinical Assessment of Disease Severity in Cervical Spondylotic Myelopathy and Predicts Outcome following Surgery
The relationship between DTI findings and clinical severity of cervical myelopathy due to spondylosis was studied in 30 patients. Low fractional anisotropy correlated with initial clinical assessments and patients with high FA showed better outcome. T2 signal intensity was associated with functional status but did not predict outcome whereas degree of stenosis lacked correlation with all clinical parameters. Thus, DTI may be a useful diagnostic tool for assessing disease severity in these patients and its predictive value regarding postoperative outcome may improve surgical decision making.
- Cervical Spine MR Imaging Findings of Patients with Hirayama Disease in North America: A Multisite Study
The authors sought to determine if Hirayama disease in North America has the same imaging findings as it does in Asia. They assessed imaging studies in 21 patients and looked for loss of attachment of posterior dura, lower cord atrophy and high T2 signal, loss of cervical lordosis, and anterior dural shift in flexion. These 4 findings were able to discriminate patients from healthy controls. MR imaging findings in white North American patients with Hirayama disease include loss of attachment on neutral images and forward displacement of the dura with flexion. Findings are often present on neutral MR images and, in the appropriate clinical scenario, should prompt flexion MR imaging to evaluate anterior dural shift.