MRI Study On Brain Functional And Structural Changes In Patients With First-episode Panic Disorder

Object The aim of this study was to explore brain functional and structural pathological mechanism in first-episode panic disorder (PD), by blood oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI) and voxel-based morphometric(VBM) technology.Methods Twenty four first-episode, treatment-naive and no complications patients with PD,18 to 44 years old (according to the diagnostic criteria of DSM-IV-TR Handbook of Differential Diagnosis, SCID-I/P), and Twenty four healthy controls were enrolled. All subjects were assessed using Hamilton Anxiety Rating Scale (HAMA), Hamilton Depression Rating Scale (HAMD), HAMA scores≥18, and HAMD scores≤12 were needed in patients, and both HAMA and HAMD scores< 7 were needed in controls. Then, all subjects accepted the MRI scans and ecStroop task during fMRI.Results Twenty four patients and twenty four controls finished MRI scan. Some data were excluded because of head movement. Data could be analyzed finally including 18 patients (15 males,3 females) in 3D and 15 patients (9 males,6 females) in fMRI; Data of 18 patients and 18 age-and education-matched healthy controls (8 males,10 females) were analyzed in 3D part, and 15 patients and 15 age-and education-matched healthy controls (9 males,6 females) were analyzed in fMRI part. The result showed that 1. Compared to healthy controls, PD patients showed significantly decreased gray matter volume in left superior temporal gyrus, right medial frontal cortex, left middle occipital gyrus, right thalamus media dorsal nucleus, right anterior cingulate cortex; there was no significantly increased gray matter volume in any brain area in patients; 2. Panic-related words compared with neutral words, left thalamus, frontal gyrus, anterior cingulated cortex, inferior frontal gyrus and insula had increased activation in patients compared to healthy controls; Right pons and lingual gyrus had increased activation in patients.Conclusions 1. We found in patients with first-episode panic disorder structural and functional abnormalities in several brain regions involved in fear circuitry. The thalamus has deficit in gating sensory information, and the "top-down" regulation of medial frontal cortex and anterior cingulate cortex is altered in PD; the damaged insula failed to control interoceptive information, and the subcortex nucleus is easier to be activated which leads to symptoms of PD.2. In our study increased activation was seen in midbrain pons in first-episode PD patients, which confirms that brainstem is related to the pathogenesis of PD; the PD patients are first-episode, treatment-naive and they have relative short disease duration, maybe that's why no significant alteration in brainstem volume.3. This study showed that PD patients have relative decreased gray matter volume in superior temporal gyrus early in the disease, and proved that temporal cortex is altered in PD patients.4. The occipital cortex had increased activation in PD patients, for the occipital cortex is involved in attentional bias, we suppose PD patients have attentional bias to the processing of threatening information.