INVERSION-RECOVERY FAST SPIN-ECHO MR-IMAGING - EFFICACY IN THE EVALUATION OF HEAD AND NECK LESIONS

To compare the efficacies of fast spin-echo (FSE) and inversion-recove ry FSE (IRFSE) magnetic resonance (MR) imaging in evaluating head and neck disorders, the authors evaluated 46 lesions in 23 consecutive pat ients. Twenty-seven lesions were related to neoplasms; 19 lesions resu lted from infectious, allergic, or radiation-induced inflammation. Con ventional T1-weighted, FSE, and IRFSE images were obtained in all pati ents. The FSE and IRFSE images were qualitatively compared in an unbli nded manner for conspicuity of lesion margins and extent. IRFSE imagin g improved conspicuity of 22 lesions (48%) and showed equal conspicuit y of 18 (39%). IRFSE imaging proved most useful for small lesions with long T2 relaxation times that were surrounded by fat. IRFSE imaging i mproved visibility of small optic nerve gliomas, salivary gland inflam mation, peripheral nerve tumors, and small lymph nodes. Early changes secondary to spread of tumor across fascial planes were also well visu alized with IRFSE sequences. In six lesions (13%) that did not have lo ng T2 relaxation times, the FSE images provided better conspicuity. Th e authors conclude that by improving conspicuity of small lesions adja cent to or surrounded by fat, IRFSE sequences can supplement FSE seque nces in imaging the head and neck.