Abstract:Objective To explore the value of bedside cranial ultrasound（BCUS）combined with serum glial fibrillary acidic protein（GFAP）in the diagnosis of brain injury and prognostic assessment of neurodevelopmental outcomes in asphyxiated premature infants，to provide a basis for early identification of high-risk infants and optimization of clinical management. Methods Using a prospective observational study method，100 asphyxiated premature infants admitted to Jiangyin People??s Hospital from February 2023 to December 2024 were successively enrolled as the study group，and100 gestational age-matched premature infants without asphyxia admitted in the same period were served as the control group. Based on BCUS findings and clinical neurological symptoms，the study group was further divided into brain injury subgroup（n=80）and non - brain injury subgroup（n=20）. All infants underwent BCUS examination and serum GFAP detection within 3 days after birth. The brain injury subgroup was further classified into good prognosis［developmental quotient（DQ）≥76，n=46］and poor prognosis（DQ≤75，n=34）subgroups according to the DQ Results of Gesell Developmental Schedules at the corrected gestational age of 6 months. The rates of BCUS abnormalities and serum GFAP levels were compared among all groups. Receiver operating characteristic（ROC）curves were plotted to analyze the diagnostic and predictive efficacy of each index，and the area under the curve（AUC）and its 95%CI were calculated. Multivariable logistic regression analysis was used to identify the independent predictors of poor prognosis.Results The rates of BCUS abnormalities and serum GFAP levels in the brain injury subgroup were significantly higher than those in the non-brain injury subgroup and the control group（P<0.017），respectively. The above two indicators in the poor prognosis subgroup were also higher than those in the good prognosis subgroup（P<0.05）. ROC curve analysis showed that BCUS combined with GFAP had an AUC of 0.949（95%CI ：0.886-0.983）for diagnosing brain injury，with a sensitivity of 94.00% and a specificity of 91.00%；for predicting poor prognosis，the AUC was 0.974（95%CI ：0.900-0.998），with a sensitivity of 94.59% and a specificity of 95.24%. Multivariate logistic regression analysis showed that after adjusting for corrected gestational age and asphyxia degree，abnormal BCUS findings（OR =4.213，95%CI ：1.828-9.710）and serum GFAP level ≥3.09 ng/mL（OR =4.859，95%CI ：1.453-16.252）were independent predictors of poor neurodevelopmental outcome in asphyxiated premature infants. Conclusion Bedside cranial ultrasound combined with serum GFAP can improve the ability of early identification of brain injury in asphyxiated premature infants and has a good predictive value for neurodevelopmental outcomes. Abnormal BCUS findings and elevated serum GFAP level are independent predictors of poor prognosis.