Posterior spinal artery syndrome showing marked swelling of the spinal cord: a clinico-pathological study

Abstract

Objective: To describe a rare autopsy case of posterior spinal artery syndrome with marked swelling of the spinal cord, an unusually subacute onset and short clinical course.

Methods: Case report.

Findings: An 84-year-old Japanese woman presented with bilateral muscle weakness of the lower legs and sensory disturbance 1 week after head contusion. Neurological findings worsened gradually. She developed phrenic nerve paralysis and died of respiratory failure 6 weeks after the onset of neurological symptoms. On pathological examination, the spinal cord was markedly swollen in the cervical and upper thoracic segments. Microscopically, there was loss of myelin sheath in the bilateral posterior columns and neuronal loss of the posterior horns in all of the spinal segments. However, findings were unremarkable in the bilateral anterior columns and bilateral anterior horns in most of the spinal segments. Posterior spinal arteries had no stenosis, occlusion, or thrombosis. We considered that pathogenesis was infarction associated with head injury.

Conclusion: To our knowledge, this is the first report of a case of posterior spinal artery syndrome with a markedly swollen spinal cord and poor prognosis.

Figure 1

Spinal MRI showing marked swelling (indicated by yellow arrows) of the spinal cord in the cervical and upper thoracic segments. (A) T1-weighted sagittal image indicating marked swelling of the cervical and upper thoracic segments of the spinal cord with signal elongation. (B, C) T2-weighted sagittal image revealing that there is widespread marked swelling of the cervical and upper thoracic segments of the spinal cord with signal elongation. (The cervical and upper thoracic spinal region (B), the lower cervical and thoracic spinal region (C).) (D) Post-contrast-enhanced T1-weighted image demonstrating heterogeneous enhancement in the upper thoracic segments of the spinal cord. (E) A T2-weighted axial image indicating the cervical spinal cord is markedly swollen, and occupies the cerebrospinal fluid space.

Figure 2

Pathological findings. (A) Macroscopic findings of the brain. The frontal cut surface of the brain shows neither hemorrhage nor edema. (B) Macroscopic finding of the spinal cord. The cervical and upper thoracic segments of the spinal cord show marked swelling, whereas the other segments show unremarkable changes. The swollen area of the spinal cord is indicated by black arrows. (C) Cervical cord is markedly swollen with demyelination of the bilateral posterior region (Klüver-Barrera staining). (D) Lumbar cord has no swelling with demyelination of the bilateral posterior region (Klüver-Barrera staining). (E, F) Microscopic findings of the spinal cord (hematoxylin and eosin staining). (E) Neuronal cells are preserved in the anterior horn of the cervical cord. (F) Neuronal cells are decreased and pyknotic in the posterior horn of the cervical cord. Many reactive glial cells are identified. Bars: (A, B) 10 mm, (C, D) 5 mm, (E, F) 50 µm.