Objective To quantitatively study the posterior fossa effective space and its relationship with hemifacial spasm (HFS).Methods We conducted a case-control study of patients diagnosed with HFS and sex-and age-matched healthy controls.All subjects underwent high-resolution three-dimensional MRI.The software of 3D-Slicer was used to measure the posterior fossa space and hindbrain tissue volume between the two groups.Results Sixty patients and 60 controls were enrolled in this study.Compared to controls,patients with HFS had a higher posterior fossa crowdedness index (PFCI;83.7％ ± 0.6％ vs 79.2％ ± 0.4％;t =2.58, P =0.01).The multivariate linear regression analysis revealed that a higher PFCI was associated with younger age (r =-0.61, P =0.02), female gender (r =0.76, P =0.003) and HFS (r =-0.43, P =0.01).Conclusions Patients with HFS have a more crowded posterior fossa space than healthy controls, potentially leading to cranial nerve and vascular structure crowding, thus increasing HFS risk.Women have a higher PFCI, which may explain the strong female preponderance in epidemiologic studies.

ObjectiveTo explore the effects of hyperbaric oxygen (HBO) on severe brain injury. Methods60 patients with severe brain injury were divided into control group and treatment group. They were treated with neurosurgical conventional therapy, and HBO for treatment group in addition. They were assessed with Glasgow Coma Scale (GCS) before and after treatment, and Glasgow Outcome Scale (GOS) 3 and 6 months after treatment. ResultsCompared with control group, there is significant improvement in GCS (P<0.05) and GOS (P<0.05) in treatment group. ConclusionHBO has immediate and long-term efficiency on severe brain injury.

Objective To investigate the effect of hyperbaric oxygen preconditioning (HBO) on activation of extracellular signal-regulated kinase (ERK) and death-associated protein kinase 1 (DAPK1)in ischemia-like treated neurons.Methods (1) Cultured mouse primary neurons were allocated into control,ischemia-like condition treated and HBO preconditioning groups.Neurons in ischemia-like condition treated group were treated with 95％ NO2+5％ CO2 for 30 min,and cells in the HBO preconditioning group were pretreated with 98％ O2+2％ CO2 for 2 h,followed by ischemia-like condition treatment.At the end ofthe treatment,the growth of neurons was measured by MTT assay and expression of phosphorylated extracellular signal-regulated kinase (p-ERK) was detected by Western blotting.Neurons were transfected with ERK over-expression vector and pretreated with HBO and ischemia-like condition,and then,the expressions of activated caspase-3 (cleavage caspase-3) and DAPK1 in neurons were analyzed by Western blotting.The interactions of ERK with DAPK1 were also detected by irnmunoprecipitation.(2) Forty-five BALB/c mice were randomized into control,ischemia treated and HBO preconditioning groups.After finishing the treatments,the interactions of ERK with DAPK1 in hippocampal neurons were detected by immunoprecipitation.Results As compared with control group,cells in ischemia-like condition group showed a reduction of cell survivals,while cells in HBO preconditioning group exhibited an inhibition effect on ischemia-like condition-induced cell survival reduction.The expressions of p-ERK were increased by ischemia-like condition,while decreased by HBO preconditioning,with significant difference (P＜0.05).Moreover,over-expression of ERK promoted level of cleavage caspase-3 in neurons; however,DAPK1 expressions were not affected by ischemia-like condition or HBO preconditioning.The interactions of ERK with DAPK1 were attenuated by HBO preconditioning as compared with those by ischemia-like condition treatment.Conclusion HBO preconditioning inhibits ERK activation and disturbs the interaction between ERK and DAPK1,which blocks cell apoptosis and thus induces ischemic tolerance.