The Role of CT in Cervical Spine Imaging for Suspected Cervical Myelopathy

Cervical spinal canal stenosis is a degenerative condition that may lead to myelopathy. While MRI is the preferred modality for detecting changes in spinal cord signal, CT is superior in assessing bony structures. The diagnostic accuracy of these modalities in measuring canal narrowing remains a topic of debate.

We conducted a retrospective study of 20 patients with cervical myelopathy who underwent both CT and MRI before surgical decompression. Thecal sac and spinal canal areas were measured at C2-T1 levels. Paired t-tests and Pearson correlations were used to compare CT and MRI measurements. Myelomalacia was assessed on MRI and correlated with cross-sectional areas.

CT consistently reported larger thecal sac and spinal canal areas compared with MRI, with statistically significant differences at all levels (e.g., C3-C4 spinal canal area: CT 1.76 ± 0.37 cm2 vs. MRI 1.40 ± 0.60 cm2, P = 0.01). Correlations between CT and MRI were moderate to strong for spinal canal area (r = 0.47 to 0.74), but weaker for thecal sac dimensions. At C6-C7, CT-derived canal area ≤1.32 cm2 was significantly associated with myelomalacia (P = 0.007).

This study suggests that CT offers superior anatomical assessment of canal narrowing and better predicts the occurrence of myelomalacia than MRI. Multimodal imaging is crucial in evaluating cervical myelopathy, and the use of CT should be considered, especially when MRI findings are inconclusive.