Resting-state cortico-limbic functional connectivity pattern in panic disorder: Relationships with emotion regulation strategy use and symptom severity.

Cognitive reappraisal is an effective emotion regulation strategy involving prefrontal cortex (PFC) control of the amygdala. Its aberrant functioning is closely associated with panic disorder (PD). However, the resting-state functional connectivity (rsFC) between the PFC, implicated in cognitive reappraisal, and the amygdala in PD has not been studied. Thus, this study aims to investigate the rsFC patterns and their association with cognitive reappraisal and PD. This study involved 51 participants, including 26 untreated patients with PD and 25 healthy controls (HC). We evaluated the habit of cognitive reappraisal assessment and the severity of PD using neuropsychological and clinical measures. Resting-state fMRI was utilized to evaluate the rsFC pattern between the PFC, engaged in cognitive reappraisal, and the amygdala. Mediation analysis was performed to explore the role of this rsFC in the relationship between cognitive reappraisal and PD severity. PD patients showed reduced rsFC between the PFC and the amygdala compared to HC. This weakened rsFC was associated with the severity of PD symptoms. Moreover, cognitive reappraisal was negatively correlated with PD severity, and mediation analysis indicated that the rsFC of the PFC-amygdala played a mediating role in this association. Abnormal PFC-amygdala rsFC may play a pivotal role in PD development and/or manifestation and mediate the association between cognitive reappraisal and PD severity, potentially serving as a clinical indicator for monitoring and intervention.

Preoperative vascular heterogeneity and aggressiveness assessment of pituitary macroadenoma based on dynamic contrast-enhanced MRI texture analysis.

PURPOSE: To assess the vascular heterogeneity and aggressiveness of pituitary macroadenomas (PM) using texture analysis based on Dynamic Contrast-Enhanced MRI (DCE-MRI). METHOD: Fifty patients with pathologically confirmed PM, including 32 patients with aggressive PM (aggressive group) and 18 patients with non-aggressive PM (non-aggressive group), were included in this study. The preoperative DCE-MRI and clinical data were collected from all patients. The features based on Ktrans, Ve, and Kep were generated using Omni-Kinetics software. Independent-samples t-test and Mann-Whitney U test were used for comparison between two groups. Logistic regression analysis was used to determine the optimal model for distinguishing aggressive and non-aggressive PM. RESULTS: Six features related to tumor morphology, 24 features in Ktrans, 20 features in Ve, and 3 features in Kep were significantly different between the aggressive and non-aggressive groups. Volume count, gray-level non-uniformity in Ktrans, voxel value sum in Ve and run-length non-uniformity in Kep (AUC = 0.816, 0.903, 0.785, 0.813) were considered the best feature for tumor diagnosis. After modeling, the diagnosis efficiency of mean model and total model was desirable (AUC = 0.859 and 0.957), and the diagnostic efficiency of morphological, Ktrans, Ve and Kep features model was improved (AUC = 0.845, 0.951, 0.847, 0.804). CONCLUSIONS: Texture analysis based on DCE-MRI elucidates the vascular heterogeneity and aggressiveness of pituitary adenoma. The total model could be used as a new noninvasive method for predicting the aggressiveness of pituitary macroadenoma.

Resting state fMRI observations of baseline brain functional activities and connectivities in primary blepharospasm.

Primary blepharospasm (BPS) is a focal dystonia characterized by involuntary eyelid spasms and blinking. The pathophysiology of BPS remains unclear. Several functional and structural neuroimaging studies have demonstrated abnormalities of sensorimotor structures such as the sensorimotor cortex, the basal ganglia, the thalamus and the cerebellum in BPS patients. However, some of the results of these studies were inconsistent. In addition, the relationship between the motor and sensory structures in patients with BPS still needs to be investigated. Therefore, the purpose of this study was to investigate the abnormal alterations in both the intra-regional brain activities and inter-regional functional connectivities (FC) in patients with BPS using resting-state functional MRI(rs-fMRI) and to explore possible correlations between these rs-fMRI indices and clinical variables. The rs-fMRI images of the two groups of subjects (26 BPS patients and 26 healthy controls) were acquired using a 3.0T MRI scanner. The regional rs-fMRI indices, i.e., the fractional amplitude of the low-frequency fluctuation (fALFF) and the regional homogeneity (ReHo), were computed for all subjects. Then, two-sample t-tests were conducted to assess the significant differences between the two groups of subjects. To investigate the alterations in brain networks, cerebral regions with significant differences were used as regions of interest in the whole brain FC analysis. Compared to the control group, the BPS patients revealed significantly increased fALFF and ReHo values in the right caudate head. Significantly strengthened FC values were observed between the right caudate head and the left striatum and the right supplementary motor area in the BPS group. The fALFF and ReHo values in the right caudate head and the FC values between the right caudate head and the left striatum were positively correlated with the Jankovic Rating Scale sum score. In conclusion, this study indicated that BPS patients have both abnormal intra-regional spontaneous brain activities and inter-regional functional connectivities.

Multiple Neural Networks Malfunction in Primary Blepharospasm: An Independent Components Analysis.

Primary blepharospasm (BPS) is a focal dystonia characterized by involuntary blinking and eyelid spasms. The pathophysiology of BPS remains unclear. Several neuroimaging studies have suggested dysfunction of sensory processing and sensorimotor integration, but the results have been inconsistent. This study aimed to determine whether patients with BPS exhibit altered functional brain connectivity and to explore possible correlations between these networks and clinical variables. Twenty-five patients with BPS and 25 healthy controls were enrolled. We found that the patient group exhibited decreased connectivity within the sensory-motor network (SMN), which involved regions of the bilateral primary sensorimotor cortex, supplementary motor area (SMA), right premotor cortex, bilateral precuneus and left superior parietal cortex. Within the right fronto-parietal network, decreased connections were observed in the middle frontal gyrus, dorsal lateral prefrontal cortex and inferior frontal gyrus. Regarding the salience network (SN), increased connectivity was observed in the left superior frontal gyrus and middle frontal gyrus. These findings suggest the involvement of multiple neural networks in primary BPS.

DTI Study of Cerebral Normal-Appearing White Matter in Hereditary Neuropathy With Liability to Pressure Palsies (HNPP).

The majority of previous studies on hereditary neuropathy with liability to pressure palsies (HNPP) were focused on peripheral nerves, whereas cerebral alterations in HNPP have been less attended to. In this work, Diffusion tensor imaging (DTI) was used to detect the changes in WM, especially in the normal-appearing white matter (NAWM) in HNPP patients for its sensitivity in probing the microstructure of WM, the sensitive metric was searched for probing cerebral alterations and the regional distribution of cerebral abnormalities was identified. Twelve HNPP patients and 12 age- and gender-matched healthy controls underwent the conventional MRI, DTI scan, and electrophysiological examination. The conventional MRI images were first analyzed to identify abnormal intense regions and the NAWM regions. NAWM refers to the white matter regions that do not include the lesions on conventional MRI. The apparent diffusion coefficient and fractional anisotropy (FA) values of the NAWM were then measured and compared between patient and control groups. The sensitivity and specificity of 3 methods and the cerebral regional distribution of MR signal abnormalities were further analyzed. Hyperintense foci were observed on T2 weighted image and fluid attenuated inversion recovery images in 6 patients. Compared to the controls, FA values of the patients were significantly lower in bilateral frontal, orbitofrontal, and temporal NAWMs; whereas the electrophysiological examination results of patients and controls exhibited no statistically significant difference. The sensitivity of FA value was higher than that of electrophysiological examination and conventional MRI. The majority of abnormal signals on conventional MRI images and abnormal FA values were located in the frontal and temporal lobes. The results of our study show cerebral WM changes in HNPP patients. FA value in DTI has been shown to be sensitive to the cerebral microstructural changes in HNPP. The frontal lobe is the predilection site that is most involved in HNPP.

Hemichorea associated with nonketotic hyperglycemia: clinical and neuroimaging features in 12 patients.

BACKGROUND: Nonketotic hyperglycemia is a rare cause of hemichorea. Patients with hemichorea associated with nonketotic hyperglycemia (HCNH) always have a favorable prognosis when given prompt treatment. METHODS: We reviewed the medical records of 12 patients with HCNH in our hospital between January 2005 and January 2013. The clinical data, laboratory findings, and imaging features of the patients were collected. RESULTS: All 12 patients were admitted to the hospital with a complaint of involuntary movements. Ten patients had a history of diabetes, while the other 2 patients had not been diagnosed. The mean level of blood glucose on admission was 330.7 ± 107.8 mg/dl, and the ketones were negative. A cranial computed tomography scan showed hyperdensity in the striatum, which quickly resolved. Magnetic resonance imaging showed hyperintensity on T1-weighted images without change over several months. Nearly all of the patients experienced relief from the hemichorea symptoms after correcting hyperglycemia with a combination of dopamine receptor inhibitors and the sedative lorazepam, if necessary. CONCLUSION: HCNH is a benign disorder, the pathogenesis of which remains unclear. Radiologic changes can provide guidance for early treatment and generally give an estimation of the degree of injury.