In patients suffering from internal derangement of temporomandibular joint (TMJ), both sideways and rotational displacement of the TMJ menisci are common, and most cases have bilateral involvement. The purpose of this study was to evaluate the value of bilateral cornal images of TMJs in patients suspected of internal derangement. Seventy-nine TMJs in totally 40 patients were studied using magnetic resonance imaging techniques including: 1) oblique sagittal, T1-weighted spin echo images in the closed -and opened-mouth positions in 79 TMJs; 2) oblique sagittal, multiplanar gradient recalled images in the closed-mouth projection in 43 TMJs; 3) oblique coronal, spin echo, T1-weighted images in the closed-mouth position in 65 TMJs. Bilateral coronal and sagittal images in the closed- and opened-mouth positions were obtained in 25 patients. With the additional use of oblique coronal images, the diagnosis changed from normal to abnormal in one joint and from anterior displacement to rotational displacement in TMJs. Bilateral TMJs were involved with internal derangement in 16 of 25 patients. Joint clicking was significantly more common in patients with less mobile menisci overlying mandibular condyles with normal or increased mobility. Our results indicated routine use of oblique coronal images is valuable in the detection of rotational and sidweways displacement. Use of a dual TMJ surface coil is suitable for detection of bilaterally displaced menisci. ; 醫學系放射線科 ; 醫學系 ; 醫學院 ; 期刊論文