ESCC scale

The ESCC scale is an assessment method proposed by Bilsky et al. in which the degree of compression by tumor is evaluated using a T2-weighted axial view of magnetic resonance imaging (MRI) [8]. The ESCC scale is comprised of six grades: grade 0 represents invasion localized in the bones (bone involvement alone), grade 1 represents epidural compression (epidural impingement), grade 2 represents spinal cord compression with visible cerebrospinal fluid retention (spinal cord compression, but cerebrospinal fluid [CSF] visible), and grade 3 represents severe spinal cord compression without visible CSF (spinal cord compression, but no CSF seen). Grade 1 is further divided into three subgroups: grade 1a represents epidural advancement without deformation of the dural canal (epidural impingement, but no deformation of the thecal sac), grade 1b represents dural canal compression without contact with the spinal cord (deformation of the thecal sac, but without spinal cord abutment), and grade 1c represents dural canal deformities with contact with the spinal cord, but without spinal cord compression (deformation of the thecal sac with spinal cord abutment, but without compression) (Fig. 1).