Brain mapping studies have shown abnormal changes in cerebral blood volume and oxygen consumption, or other neurophysiological abnormalities, in panic disorder (PD) patients. Because of these intriguing reports, we decided to assess the neuroanatomical aspects of patients with PD using magnetic resonance imaging (MRI). We included 31 consecutive cases with a diagnosis of PD according to the DSM-III criteria, and 20 controls. All subjects had to be right-handed and between 20 and 40 years of age. The usual exclusion criteria were applied. We carried out the MRI tests with a General Electric Signa Machine operating at 1.5 Tesla. Over 100 images were obtained per patient with an emphasis on assessing temporal lobe. There were no significant differences in age, gender, or weight between the patients and controls. We found a statistically significant higher number of abnormalities in PD patients (40%), as compared with the controls (10%). The most striking findings were focal abnormalities in the temporal lobes: areas of abnormal signal activity, and asymmetric atrophy of the temporal lobe occurred mostly on the right side. These results implicated the limbic system and may prove to be of particular relevance in panic and phobic disorders. However, the significance of our findings remains unknown and challenging. Further MRI studies in PD will be required for a better understanding of the illness.