Thoracic disc herniation leads to anterior spinal artery syndrome demonstrated by diffusion-weighted magnetic resonance imaging (DWI): a case report and literature review.

BACKGROUND: Thoracic disc herniation rarely causes acute ischemic events involving the spinal cord. Few reports have suggested this as a mechanism leading to anterior spinal artery syndrome, and none with illustration through diffusion-weighted magnetic resonance imaging (DWI). PURPOSE: The purpose of this study was to report a case of anterior spinal artery syndrome secondary to thoracic disc herniation and demonstrate the first use of DWI to aid in diagnosis of this rare myelopathy. STUDY DESIGN: Case report. METHODS: A 36-year-old woman developed sudden onset of back pain followed by evolving paraparesis and sensory loss consistent with anterior spinal artery distribution ischemia. T2-weighted magnetic resonance imaging (MRI) demonstrated an acute herniated nucleus pulposus at the T7-T8 disc, which produced a focal indentation of the adjacent anterior spinal cord without cord displacement or canal stenosis. T2-weighted hyperintensities were seen at T4-T7 levels with corresponding brightness on DWI and reduction of the apparent diffusion coefficient, consistent with cord ischemia. RESULTS: Remarkably, within just a few days and following conservative treatment, including heparin and steroids, this patient's neurologic status began to show improvement. Within 3 weeks, she was ambulating with assisted devices, and at the 10-month follow-up, the patient had nearly complete neurological improvement. A follow-up MRI at 10 months showed normal T2-weighted imaging except for a 1×2-mm area of anterior-left lateral cord myelomalacia at T4-T5. CONCLUSIONS: Acute thoracic disc herniation with cord contact but without canal stenosis is able to disrupt blood flow to the cord leading to anterior spinal artery distribution ischemia. This case represents the first demonstrated use of DWI in diagnosing this rare cause of anterior spinal artery ischemia.

Resolution of an aggressive ideopathic diskitis.

We report a case of thoracic spine diskitis of unknown cause that had aggressive and destructive features on MR images. Results of two biopsies were unremarkable. The process began after sneezing, also produced extensive paraspinous enhancement, and resolved without antibiotic therapy both clinically and radiologically after four months. A discussion of case similarities to Reflex Sympathetic Dystrophy (RSD) in the extremities render this possibly the first reported imaging evidence of RSD in the axial skeleton.

Swimmer's CT: improved imaging of the lower neck and thoracic inlet.

CT findings of the base of the neck are often degraded by beam-hardening artifact from the shoulder girdle. This artifact can be reduced by placing the patient in a "swimmer's" position, a supine position in which the patient has one arm fully abducted and the other arm lowered. We selectively employed swimmer's CT in patients between January 1999 and December 2002 when standard (arms-down) CT failed to depict suspected disease. In nine of 10 patients, swimmer's CT improved CT quality or accuracy or both over that obtained when the standard CT position was used.

MR imaging of heat stroke: external capsule and thalamic T1 shortening and cerebellar injury.

We present a case of increased signal intensity of the cerebrum (symmetric involvement of the paraventricular thalamus and external capsule) and cerebellum on both T1- and T2-weighted images in a patient with documented heat stroke. An ischemic and hemorrhagic mechanism is proposed, and the contributions of the direct effects of hyperthermia are discussed.