Thoracic spinal eosinophilic granuloma: a case report and literature review

Objectives: To illustrate the image findings of thoracic spinal eosinophilic granuloma and to strengthen the ability of differential diagnosis for spinal vertebral destructive diseases. Methods: Images of a case with thoracic spinal eosinophilic granuloma were analyzed and literatures of imaging diagnosis of spinal vertebral destruction with the surrounding soft tissue shadow were reviewed. Results: Precontrast CT scan revealed a collapse of T₇ vertebral body, dissolved bony destruction of T₆ & T₈ vertebral body, and extension to paravertebral soft tissue and epidural space without invasion to adjacent disc spaces. MRI showed a collapse of T₇ vertebral body, hypointensity on T₁WI, mild hyperintensity on T₂WI and T₂WI FLAIR, which was embedded in a paravertebral soft tissue; the signal of the T₆ & T₈ vertebral body showed mild hyperintensity on the T₂WI FLAIR. Enhanced scan showed both the lesions and the surrounding soft tissue were enhanced. Immunohistochemistry showed Langerhans cell histiocytosis. Conclusions: The key signs in the differential diagnosis of spinal eosinophilic granuloma include the vertebral destruction in the middle of the vertebral body, presence of typical 'vertebra plana', generally not involving the intervertebral disc, the similar enhancement behavior within the lesions and surrounding soft tissue, etc. (authors)