Differences between imaging features of lymphoma and infective spondylodiscitis in spine on MRI

Abstract

Introduction: Lymphoma of the spine is an uncommon manifestation of extra nodal lymphoma. Although lymphoma more commonly involves the vertebral body or epidural compartment, intramedullary lymphoma may rarely occur. Spondylodiscitis is an infection of intervertebral disc, adjacent vertebrae and paraspinaltissues either as a result of systemic spread or direct invasion of the spine.

Objective: To evaluate differences between imaging features of lymphoma vs. infective spondylodiscitis.

Materials and methods: In a retrospective observationalstudy, we included diagnosed cases of lymphoma and infective spondylodiscitis in the spine. The study wasconducted in radiology department of Shifa International Hospital Islamabad, 20 patients of lymphoma and 20 patients of infective spondylodiscitis were included in the study from Radiology Information system betweenJanuary 2018 to December 2022. Frequencies and percentages were used for categorical variables. Levene’stest for equality of variances was applied on our data using SPSS version 23 to look for statistically significant variables.

Results: Intervertebral disc involvement was most commonly seen in patients of infective spondylodiscitiswhile very few cases of lymphoma showed this feature either in cervical, lumbar or dorsal spine. Contiguous involvement of 1-3 vertebral bodies was more commonly seen in infective spondylodiscitis while in lymphoma diffuse marrow signal abnormality involving whole spine was common. Pre, para spinal abscesses were seen in patients of infective spondylodiscitis while masses in patients of lymphoma. Pre and para spinal abscesses/masses, epidural abscess/mass and vertebral bodies involvement in cervical spine, spinal cord enhancement in lumbar spine and lymph node involvement as a whole were significantly different variables in these two study groups. We had two patients where there was some overlap of findings, and it was difficult to diagnose on imaging, one of them was proven as infective spondylodiscitis and the other one as lymphoma which initially presented as infective spondylodiscitis on imaging. Therefore, Lymphoma can present as infection on imaging.

Conclusion: MRI is a modality of choice in diagnosing infective spondylodiscitis It also can help us differentiate it from lymphoma in majority of the cases. However, in a small percentage of population, overlap of imaging features can occur.

Keywords: lymphoma, spondylodiscitis, abscess.