Is there an Added Value of T1-Weighted Contrast-Enhanced Fat-suppressed Spin-Echo MR Sequences Compared to STIR Sequences in MRI of the Foot and Ankle?

OBJECTIVES

To prospectively compare T1-weighted fat-suppressed spin-echo magnetic resonance (MR) sequences after gadolinium application (T1wGdFS) to STIR sequences in patients with acute and chronic foot pain.

METHODS

In 51 patients referred for MRI of the foot and ankle, additional transverse and sagittal T1wGdFS sequences were obtained. Two sets of MR images (standard protocol with STIR or T1wGdFS) were analysed. Diagnosis, diagnostic confidence, and localization of the abnormality were noted. Standard of reference was established by an expert panel of two experienced MSK radiologists and one experienced foot surgeon based on MR images, clinical charts and surgical reports. Patients reported prospectively localization of pain. Descriptive statistics, McNemar test and Kappa test were used.

RESULTS

Diagnostic accuracy with STIR protocol was 80% for reader 1, 67% for reader 2, with contrast-protocol 84%, both readers. Significance was found for reader 2. Diagnostic confidence for reader 1 was 1.7 with STIR, 1.3 with contrast-protocol; reader 2: 2.1/1.7. Significance was found for reader 1. Pain location correlated with STIR sequences in 64% and 52%, with gadolinium sequences in 70% and 71%.

CONCLUSIONS

T1-weighted contrast material-enhanced fat-suppressed spin-echo magnetic resonance sequences improve diagnostic accuracy, diagnostic confidence and correlation of MR abnormalities with pain location in MRI of the foot and ankle. However, the additional value is small.

KEY POINTS

• Additional value of contrast-enhanced MR over standard MR with STIR sequences exists. • There is slightly more added value for soft tissue than for bony lesions. • This added value is limited. • Therefore, application of contrast material cannot be generally recommended.