[Objective] To evaluate the efficacy of reinforcing short-segment pedicle screw fixation with posterior morselized bone grafting in vertebrae for spinal fusion in patients with thoracolumbar vertebrae fractures.[Method]Seventy patients with thoracolumbar vertebrae fractures were treated with short-segment pedicle screw fixation.Fractures in Group A(n =20) were reinforced with posterior morselized bone grafting in vertebrae for spinal fusion.Group B patients(n =50) were not treated with morselized bone grafting.Kyphotic deformity,anterior vertebral height,instrument failure rates,and neurological function outcomes were compared between the two groups.[Result]Kyphosis correction was achieved in Group A(morselized bone grafting) and Group B(Group A,6.4 degrees,Group B,5.4 degrees).At the end of the follow-up period,kyphosis correction was maintained in Group A but lost in Group B(Group A,0.33-degree loss,Group B,6.20-degree loss)(P=0.0001).After surgery,greater anterior vertebral height was achieved in Group A than in Group B(Group A,12.9%,Group B,2.3%)(P

Objective To evaluate the efficacy of aminophylline for prevention of the negative chronotropic effect of remifentanil.Methods Forty patients undergoing general anesthesia,aged 20-55 yr,with body mass index of 18-25 kg/m2,of ASA physical status Ⅰ or 1Ⅱ,were randomly divided into control group (group C) and aminophylline group (group AP),with 20 patients in each group.At 30 min before induction of anesthesia,normal saline 20 ml was infused intravenously in group C,and aminophylline 3 mg/kg was infused intravenously in group AP.Midazolam 0.1 mg/kg was then injected intravenously.Remifentanil 2 μg/kg was injected intravenously after the patients fell asleep and then artificial ventilation was performed.Vecuronium 0.1 mg/kg,fentanyl 3 μg/kg,and etomidate 0.3 mg/kg were injected intravenously 7 min later.The patients were then endotracheally intubated and mechanically ventilated.HR and MAP were recorded before induction of anesthesia (T0),after falling asleep (T1),and at 0,1,3,5 and 7 min (T2-6) after the end of remifentanil injection.Low frequency (LF) and high frequency (HF) were recorded at T0,T1 and T2,and the ratio of LF/HF was calculated.Results Compared with the baseline value at T0,MAP and HR were significantly decreased at T2-6 in the two groups,and LF and HF were decreased at T1,and LF/HF ratio was increased at T1 in group AP.HR and LF/HF ratio were significantly higher,and LF and HF were lower at T1 in group AP than in group C.Conclusion The efficacy of aminophylline for prevention of the negative chronotropic effect of remifentanil on the hearts of patients is good.

This study sought to make a biomechanical analysis of the diffuse axonal injury(DAI) animal model caused by nonimpact with half bound head in cats. A three-dimensional finite element model of cat's head was established. The head of an anesthetized cat was scanned in 2 mm section. The nods and element meshes were signed out according to the geometry of every section. The geometric data were put into the computer and the element mesh body of cat's head was established in vizi CAD system. The maximum stress, minimum stress and von Mises stress were calculated by Super SAP (93ed) finite elemental software when the force was loaded on the right or left side of model in zero section. The analysis showed that the maximum stress appeared in the anterior and posterior loaded point and extended to cranial base in the cranial shell. There was high stress in the brain surface also. Because of cerebellar tentorium, cerebral falx, petrosal bone and sellar process, the stress did not decrease equivalently while approaching the deep brain, but it was distributed in cerebral-cerebellar peduncles, brain stem, corpus callosum and basal ganglia area at high values. The results suggest that the stress caused by rotational force is widespreadly and unequivalently distributed in brain tissue, which is mainly effected by the cerebellar tentorium, cerebral falx and the irregular geometric forms of cranial bone.
Animals ; Biomechanical Phenomena ; Brain ; pathology ; Brain Injuries ; pathology ; Cats ; Diffuse Axonal Injury ; pathology ; Finite Element Analysis ; Head ; Models, Animal ; Rotation ; Skull

Objective To propose a lung artery segmentation method that integrates shape and position prior knowledge, aiming to solve the issues of inaccurate segmentation caused by the high similarity and small size differences between the lung arteries and surrounding tissues in CT images. Methods Based on the three-dimensional U-Net network architecture and relying on the PARSE 2022 database image data, shape and position prior knowledge was introduced to design feature extraction and fusion strategies to enhance the ability of lung artery segmentation. The data of the patients were divided into three groups: a training set, a validation set, and a test set. The performance metrics for evaluating the model included Dice Similarity Coefficient (DSC), sensitivity, accuracy, and Hausdorff distance (HD95). Results The study included lung artery imaging data from 203 patients, including 100 patients in the training set, 30 patients in the validation set, and 73 patients in the test set. Through the backbone network, a rough segmentation of the lung arteries was performed to obtain a complete vascular structure; the branch network integrating shape and position information was used to extract features of small pulmonary arteries, reducing interference from the pulmonary artery trunk and left and right pulmonary arteries. Experimental results showed that the segmentation model based on shape and position prior knowledge had a higher DSC (82.81%±3.20% vs. 80.47%±3.17% vs. 80.36%±3.43%), sensitivity (85.30%±8.04% vs. 80.95%±6.89% vs. 82.82%±7.29%), and accuracy (81.63%±7.53% vs. 81.19%±8.35% vs. 79.36%±8.98%) compared to traditional three-dimensional U-Net and V-Net methods. HD95 could reach (9.52±4.29) mm, which was 6.05 mm shorter than traditional methods, showing excellent performance in segmentation boundaries. Conclusion The lung artery segmentation method based on shape and position prior knowledge can achieve precise segmentation of lung artery vessels and has potential application value in tasks such as bronchoscopy or percutaneous puncture surgery navigation.