Résumé
BACKGROUND:There is less report about mitigating sustained bone grinding injuries during craniotomy based on a model of traumatic brain injury established using the modified Feeney's free-fall method. OBJECTIVE:To modify a modified traumatic brain injury model by altering the opening of the skull window. METHODS:Thirty-six Sprague-Dawley rats were equally randomized into sham group,model group and modified model group.The modified procedure of opening the bone window was used in the modified model group.Six to eight small holes of 0.3-0.5 mm in diameter were punched at the edge of the impact area and the drill was immediately withdrawn without touching the cortex.In the modified model group,the skull window was opened by using the modified method,while the skull window in the model group was opened using the conventional method.The modified model group and model group were established using the Feeney's free-fall method.In the sham group,only the skull window was opened without impact.The modified neurological severity scoring was performed at 1 day after modeling.T2 weighted imaging was performed and T2 values were measured at 1 and 7 days after modeling.Hematoxylin-eosin staining of the brain section was made for histopathological observation at 7 days after modeling.The level of blood viscosity,interleukin-6,interleukin-1β,and tumor necrosis factor-α were determined at 7 days after modeling. RESULTS AND CONCLUSION:Compared with the sham group,the modified neurological severity scores in the model group and modified model group were significantly increased at 1 day after modeling(P＜0.000 1).Meanwhile,the modified neurological severity scores in the modified model group were lower than those in the model group(P＜0.000 1).Compared with the sham group,the T2 values were significantly increased in the model group and modified model group at 1 and 7 days after modeling(P＜0.05),while the T2 values in the modified model group were lower than those in the model group(P＜0.05).Compared with the sham group,the level of blood viscosity,interleukin-6,interleukin-1β and tumor necrosis factor-α were increased in the model group and modified model group at 7 days after modeling(P＜0.05),while the level of interleukin-6 in the modified model group was lower than that in the model group(P＜0.05).To conclude,establishing a modified traumatic brain injury model based on the Feeney's free-fall method provides better controls of injury factors during cranial opening.