Objective:To explore the brain structural changes in patients with post-traumatic stress disorder (PTSD) after traffic accident.Methods:Forty-six patients with PTSD (PTSD group) who received treatment in Psychology Department, Second People's Hospital of Guangdong Province from January 2021 to June 2022 after traffic accidents and 49 gender- and age-matched normal healthy subjects (control group) were selected; all subjects underwent MRI 3D-T1WI structural imaging of the whole brain. Voxel-based morphometry (VBM) was used to detect the volume differences of the gray matter between the two groups. The correlations of volumes of the gray matter in PTSD group which was different from that in the control group with Clinician-Administered PTSD Scale (CAPS), PTSD Checklist-Civilian Version (PCL-C) and Hamilton Rating Scale for Depression (HAMD) were analyzed.Results:Compared with control group, patients in PTSD group had significantly decreased gray matter volumes in the left hippocampus, left postcentral gyrus and right superior frontal gyrus ( P<0.001, adjusted GRF); no regions with increased gray matter volumes were noted. The gray matter volume in the left postcentral gyrus was negatively correlated with CAPS scores in PTSD patients ( r=-0.443, P=0.002); the gray matter volumes in other brain regions with differences were not correlated with CAPS, PCL-C or HAMD scores ( P>0.05). Conclusion:Structural changes of the left hippocampus, left postcentral gyrus and right superior frontal gyrus are observed in PTSD patients caused by traffic accidents, and the gray matter volume of left postcentral gyrus is related to severity of PTSD clinical symptoms.

Objective:To investigate the value of quantitative ultrashort-echo-time (UTE) adiabatic T 1ρ (AdiabT 1ρ) in the diagnosis of articular cartilage degeneration of knee. Methods:A prospective case-control study was used. From March 2023 to September 2024, 30 healthy volunteers and 50 patients with osteoarthritis (OA) were recruited in the Second Affiliated Hospital, South China University of Technology and the Fifth Affiliated Hospital of Sun Yat-sen University. The unilateral knee joints were scanned by using three-dimensional (3D) UTE-Cones-AdiabT 1ρ sequence. The articular cartilages of knee were divided into 13 subregions slice by slice, with a total of 3 837 subregions. The whole-organ magnetic resonance-imaging score (WORMS) was evaluated in each subregion. According to the extent of lesions, the subregions cartilages were divided into normal group (WORMS 0, 2 589 subregions), localized lesion group (WORMS 1, 2, 2.5, 911 subregions) and diffuse lesion group (WORMS 3, 4, 5, 337 subregions). According to the depth of lesions, they were divided into normal group (WORMS 0, 2 589 subregions), partial cartilage layer lesions group (WORMS 1, 2, 3, 4, 1 108 subregions) and full-thickness lesion group (WORMS 2.5, 5, 140 subregions). WORMS 1 was early cartilage degeneration. The Kellgren-Lawrence (KL) grade of the knee joints was assessed and divided into normal group (KL grade 0, 1 323 subregions), suspicious or mild OA group (KL grades 1 and 2, 1 738 subregions), and moderate or severe OA group (KL grades 3 and 4, 776 subregions). The UTE-Cones-AdiabT 1ρ values and curves for each subregion were obtained by Matlab 2017b software. The ANOVA was used to compare the differences in UTE-Cones-AdiabT 1ρ between different WORMS groups and KL groups. Spearman correlation analysis was used to evaluate the correlation between UTE-Cones-AdiabT 1ρ and WORMS and KL groups. The receiver operating characteristic curve and area under the curve (AUC) were used to determine the efficacy of UTE-Cones-AdiabT 1ρ in diagnosing early cartilage degeneration and suspicious or mild OA. Results:Both normal volunteers and OA patients were able to obtain good cartilage images and well-fitting UTE-Cones-AdiabT 1ρ curves. There were 2 589, 569, 277, 65, 199, 63 and 75 cartilage subregions with WORMS scores of 0, 1, 2, 2.5, 3, 4 and 5, respectively, and the UTE-Cones-AdiabT 1ρ values were (36.1±5.1), (41.5±5.2), (42.3±5.3), (45.2±6.3), (43.0±5.2), (44.1±5.4) and (47.5±5.7) ms, respectively. The difference was statistically significant ( F=161.63, P<0.001). There was a statistically significant difference in UTE-Cones-AdiabT 1ρ among normal group, localized lesion group and diffuse lesion group ( F=450.92, P<0.001), and there was a significant difference in UTE-Cones-AdiabT 1ρ value among normal group, partial cartilage lesion group and full-thickness lesion group ( F=479.13, P<0.001). There was a statistically significant difference in UTE-Cones-AdiabT 1ρ among the normal group, the suspected or mild OA group, and the moderate or severe OA group ( F=36.91, P<0.001). The UTE-Cones-AdiabT 1ρ values in all subregions were positively correlated with WORMS and KL grades ( r=0.55, P<0.001; r=0.26, P<0.001). The AUC of UTE-Cones-AdiabT 1ρ in the diagnosis of early cartilage degeneration was 0.773 (95% CI 0.750-0.796), and the AUC in the diagnosis of suspicious or mild OA was 0.580 (95% CI 0.560-0.601). Conclusion:3D UTE-Cones-AdiabT 1ρ is positively correlated with the degree of cartilage degeneration, which can quantitatively evaluate cartilage degeneration and has the value of early diagnosis of articular cartilage degeneration.