LIVER LESION DETECTION, CHARACTERIZATION, AND EFFECT ON PATIENT-MANAGEMENT - COMPARISON OF SINGLE-PHASE SPIRAL CT AND CURRENT MR TECHNIQUES

This study compares liver lesion detection, characterization, and effe ct on patient management between single-phase spiral CT and MRI:using spoiled gradient echo (SGE), Ta-weighted fat-suppressed spin echo, and serial post gadolinium SGE. AU.patients with suspected liver lesions who underwent spiral CT and MRI within a 1-month period between Januar y 1993 and September 1996 were included in the study. Spiral CT and MR I were interpreted prospectively in a blinded fashion by separate indi vidual experienced investigators, and lesion detection and characteriz ation were determined. Confirmation was obtained by surgery (6 patient s), biopsy (18 patients), imaging follow-up (36 patients), or combined reading of all imaging studies and clinical follow-up (29 patients). Effect on patient management was determined by combined chart review a nd interview of the patients' physicians and by retrospective clinical assessment performed by a surgical oncologist and medical oncologist separately. Eighty-nine patients were included in the study. Regarding true positive lesion detection, 295 and 519 lesions were detected on spiral CT and MR images, respectively, which was significantly differe nt on a patient-by-patient basis (P <.001). More lesions were detected on MR than on spiral CT in 44 of 89 patients (49.4%), and 11 of these 44 patients had lesions shown on MRI in whom no lesions were apparent on CT images. No patients had true positive lesions shown on spiral C T that were not shown on MRI. Regarding lesion characterization, 129 a nd 466 lesions were characterized on spiral CT and MRI images, respect ively, which was significantly different on a patient-by-patient basis (P <.001). More lesions were characterized on MR than CT images in 67 patients (75.3%). Regarding effect on patient management, chart revie w with physician interview demonstrated that findings on MRI provided information that altered patient management as compared with findings on spiral CT in 57 patients. Retrospective clinical evaluation by the surgical and medical oncologist showed that MRI was considered to have a greater effect on patient management than spiral CT in 58 and 55 pa tients, respectively. Comparing current MRI technique to single-phase spiral CT, MRI detected more lesions in 49.4% and characterized more l esions in 75.3% of patients investigated for focal liver disease. MRI had a greater effect on patient management in each of the three method s than single-phase spiral CT in more than 61% of patients.