RESUMO
BACKGROUND: Denticulate ligaments (DLs) are pial extensions on each side of the spinal cord, comprising about 20 to 21 pairs of fibrous structures connecting the dura mater to the spinal cord. These ligaments are significant anatomical landmarks in the surgical approach to intradural structures. To our knowledge, there is no previous study on the detection of DLs using MRI. METHODS: After IRB approval, we retrospectively evaluated 116 consecutive MRI scans of the cervical spine, using the volumetric sequence 3D COSMIC, 65 and 51 studies with 1.5T and 3.0T respectively. We did not include trauma and tumor cases. Two independent radiologists assessed the detection of cervical spine DLs independently and blinded for each cervical vertebral level. We compared the frequency of detection of these ligaments in 1.5 Tesla and 3.0 Tesla MRI using Fisher exact test considering P<0.05 as significant. We evaluated interobserver agreement with Kappa coefficient. RESULTS: We observed high detection frequency of the cervical spine DLs using both 1.5T (70 to 91%) and 3.0T (68 to 98%). We found no statistically significant difference in the detection frequency of ligaments between the 1.5T and 3.0T MRI in all vertebral levels. Using 3.0T, radiologists identified ligaments better in higher vertebral levels than for lower cervical levels (P=0.0003). Interobserver agreement on the identification of DL was poor both for 1.5T (k=0.3744; CI 95% 0.28-0.46) and 3.0T (k=0.3044; CI 95% 0.18-0.42) MRI. CONCLUSIONS: Radiologists identified most of the cervical DLs using volumetric MRI acquisition. Our results suggest 1.5T and 3.0T MRI performed similarly in the detection of DLs.