The effect of gadolinium on the sensitivity and specificity of MR in the initial diagnosis of multiple sclerosis.

Purpose: To determine whether gadolinium can improve the sensitivity and specificity of MR imaging for the initial diagnosis of multiple sclerosis.
Methods: Patients (n = 57) with neurologic symptoms suggesting multiple sclerosis were studied prospectively. MR imaging consisted of T2-weighted and gadolinium-enhanced T1-weighted spin-echo images. Lumbar puncture was performed for cerebrospinal fluid analysis in 34 patients.
Results: After imaging, 17 patients (35%) had clinically definite multiple sclerosis. Cerebrospinal fluid examination had a sensitivity of 69% and specificity of 38%. Using liberal criteria, the sensitivity of T2-weighted MR imaging was 94% and the specificity 55%; using more strict criteria, the specificity increased to 65% with a sensitivity of 88%. Gadopentetate dimeglumine enhancement increased the specificity further to 80% with a loss of sensitivity (59%).
Conclusion: Gadolinium enhancement increases the specificity of MR imaging in the early diagnosis of multiple sclerosis.