Male, 49 years old, with progressive weakness of the left hand. Assess for Hirayama disease. The normal cervical lordosis is reversed with a slight anterior angulation of C2 and C3 relative to the lower cervical spine.Vertebral body heights are preserved. No areas of pathologic marrow edema or replacement are seen. Evidence of prior bilateral laminectomy is seen from C3 through C6.Cord atrophy is evident centered at C4 and C5 with a focus of frank cord T2 hyperintensity on the right at C4-5. Secondary to laminectomy, the thecal sac is well expanded between C3 and C6 on neutral imaging. With flexion, there is no change in the caliber of the thecal sac which remains well-expanded through the decompressed region, nor is it significantly changed above or below. With extension, however, there is a significant decrease in the caliber of the thecal sac with the spinal cord appearing mildly compressed between the dorsal dural surface and the vertebral bodies from C3 to C5.The following level specific findings are observed on neutral imaging:C2-3: No spinal canal stenosis or neuroforaminal narrowing. C3-4: Posterior canal decompression. Mild posterior disc-osteophyte complex formation resulting in mild bilateral foraminal narrowing. C4-5: Posterior canal decompression. Mild posterior disc-osteophyte complex formation resulting in mild bilateral foraminal narrowing. C5-6: Posterior canal decompression. Mild posterior disc-osteophyte complex formation resulting in moderate right and severe left foraminal narrowing. C6-7: Posterior canal decompression. Posterior disc-osteophyte complex formation asymmetric to the left. Moderate left foraminal narrowing. C7-T1: Posterior disc-osteophyte complex formation asymmetric to the left. No significant spinal canal stenosis. Mild bilateral foraminal narrowing.
1.Evidence of laminectomy for spinal canal decompression is seen from C3 through C6. 2.Spinal cord atrophy and signal abnormality are demonstrated at the C4 and C5 levels. The thecal sac is well expanded in this region on both the neutral and flexion views. On extension views, however, a significant decrease in the caliber of the thecal sac is seen with some degree of cord impingement suspected between the posterior dural wall and the vertebral bodies. While this is paradoxical to what is typically seen on flexion and extension imaging in Hirayama disease, the possibility certainly exists that there is some component of chronic positional cord impingement at play.3.Relatively mild degenerative disc disease is seen without significant spinal canal stenosis as assessed in the neutral position. Scattered foraminal narrowing is noted, and it does tend to be more severe on the left.