ABSTRACT
Perifoveal exudative vascular anomalous complex (PEVAC) is a very rare macular vascular disease characterized by an isolated large aneurysmal lesion in the fovea, with accompanied by small retinal hemorrhage and exudation. The main clinical symptoms of the patients are various degree of impaired vision. Clinically, it is often confused with type 1 macular telangiectasia and type 3 macular neovascularization. A thorough understanding of the clinical features of PEVAC is particularly important for its differential diagnosis. Due to the unclear pathogenesis of PEVAC, there is no specific treatment for the cause of disease. Most scholars use intravitreal injection against vascular endothelial growth factor drugs for treatment, but can not improve patients' visual acuity. At present, many attempts have been made to eliminate abnormal exudation of the lesion, maintain visual function and achieve a good prognosis by simple or combined laser photocoagulation. At present, it is still necessary to explore the pathogenesis of PEVAC, improve the understanding of the disease, and find a better treatment plan.
ABSTRACT
Objective:To explore the traits of functional connectivity of resting-state networks in patients of schizophrenia with auditory verbal hallucinations (AVH) by using independent component analysis (ICA).Methods:All patients were met the Diagnostic and Statistical Mannal of Mental Disorders,Fourth Edition,Text Revision (DSM-IV-TR) diagnostic criteria for schizophrenia.Thirty schizophrenia patients with frequent AVH (AVH),24 schizophrenia patients without AVH (non-AVH) and 60 healthy controls (HC) matching with age and gender were analyzed by resting functional magnetic resonance imaging.The AVH were assessed by using Hoffman auditory hallucination scale.By using ICA,auditory network (AUN),language network (LAN),salience network (SAN),right front-parietal network (RFP) and default mode network (DMN) were selected as interesting networks for further analyses.Covariance analysis was used to compare the activity and functional connectivity of multiple resting state networks between three groups,and correlation analysis was used to evaluate the relations between abnormalities of brain and the severity of hallucination.Results:Compared to non-AVH,AVH group showed increased activity in left superior temporal gyrus (STG) and left postcentral gyrus (LPG) in the AUN,and showed decreased activity in right anterior cingulate cortex (ACC) in the SAN (P ＜ 0.05,FDR corrected).The severity of AVH group was associated with activity of the left STG (r =0.43,P ＜0.05) and the right ACC (r =-0.48,P ＜0.01).Furthermore,compared to non-AVH group,there were decreased connectivity between LAN and AUN [(-0.29 ±0.21) vs.(-0.16 ± 0.17),P ＜ 0.05,uncorrected],decreased connectivity between SAN and LAN [(-0.09 ± 0.22) vs.(-0.06 ± 0.18),P ＜ 0.05,uncorrected],increased connectivity between SAN and AUN [(0.30 ± 0.18) vs.(0.15 ± 0.24),P ＜ 0.05,uncorrected] in AVH group.Conclusion:There may be aberrant functional connectivities of AUN,LAN and SAN in schizophrenia patients with frequent AVH,and the occurrence of AVH seems to be related to brain areas involved in language production,speech perception and self-monitoring.