To address the limitations of traditional minimally invasive thermal ablation technology such as poor conformability, carbonization and electromagnetic radiation, this paper proposes a steam thermal ablation technology that uses saturated steam internal energy to replace the traditional electromagnetic radiation energy. Through the steam thermal ablation system and the steam thermal ablation needle designed based on simulation, the ex vivo pig liver experiments were carried out. The results have the characteristics of the maximum ablation axis ratio (short diameter / long diameter) and non-carbonization with the same type of thermal ablation technology. Based on the near-infrared light, in this paper the curative effect of the reduced scattering coefficient of the steam thermal ablation results was evaluated. The reduced scattering coefficients of the coagulation area all exceeded 16, reaching the completely damaged state, which verified that the steam thermal ablation can effectively inactivate the tumor cells.
Steam ; Animals ; Swine ; Liver Neoplasms/surgery* ; Ablation Techniques/methods* ; Liver/surgery* ; Equipment Design

The minimally invasive thermal ablation technology differs from traditional surgical operations, which requires auxiliary equipment to evaluate ablation results. However, the ultrasound and CT currently used in clinical practice have shortcomings such as artifacts and radiation. Therefore, this paper proposes a design for a minimally invasive thermal ablation evaluation system based on the principle of electrical impedance tomography technology to monitor the ablation range. At the same time, the innovative introduction of a programmable gain feedforward signal as the parameter signal of the multiplier demodulator in the electrical impedance tomography system design can effectively solve the problem of weak signals being submerged in noise and improve imaging accuracy. The system controls the amplitude of the excitation current signal and the acquisition / processing of boundary voltages via an STM32, uploads the collected data to an upper computer, and reconstructs the conductivity distribution using the Newton-Raphson algorithm to map the size of the ablation area. Experimental results show that the system can effectively reflect the size of the microwave ablation area. Under the same minimally invasive ablation parameters, the average imaging errors are 0.6 mm for the long diameter, 0.8 mm for the short diameter, and 1.75% for the axial ratio (long diameter / short diameter), demonstrating high consistency. This verifies the technical potential of electrical impedance tomography in minimally invasive thermal ablation.
Electric Impedance ; Tomography/instrumentation* ; Equipment Design

BACKGROUND:The asymmetrical biomechanical environment of adolescent idiopathic scoliosis can lead to further wedge deformation of the vertebral body,which may affect cardiopulmonary function and compress nerves in severe cases.Adolescent idiopathic scoliosis with different degrees of scoliosis should be treated with exercise,bracing,and surgery.However,the mechanical mechanism of selecting an orthopedic approach remains unclear due to the individual variability of patients.OBJECTIVE:To investigate the biomechanical mechanism of different orthopedic modalities for the treatment of adolescent idiopathic scoliosis to provide a basis for clinical selection of treatment modalities based on the spine model of adolescent idiopathic scoliosis patients.METHODS:Based on the CT images of an adolescent idiopathic scoliosis patient,a scoliosis model(C7-L5)was reconstructed in Mimics software in three dimensions,and lateral thrust force was applied at the T8/T9 thorax and vertical distraction force was applied over the C7 vertebra with the magnitude of 20,40,60,80,100,and 120 N.The intervertebral disc stress and vertebral displacement in concave and convex sides,and Cobb angle of the spine were analyzed under two orthopedic modalities.RESULTS AND CONCLUSION:(1)With lateral thrust,there was no significant change in the C7T1-T7T8 intervertebral disc.The concave and convex stress of T7T8-L4L5 segment decreased first and then increased with the increase of lateral thrust force.The correction effect of lateral thrust on the segment near T8T9 was obvious and weakened with the extension of the segment to the cephalic and caudal ends.At 120 N of lateral thrust,the thoracic Cobb angle changed from 53.2° to 32.5° and the lumbar Cobb angle changed from 50.2° to 43.9°.(2)With the vertical distraction,the thoracic intervertebral disc stresses first decreased and then increased,and all the lumbar disc stresses decreased.The C7 displacement was the most obvious,and the correction effect gradually diminished with the segment extended to the caudal end.At a vertical distraction force of 120 N,the thoracic Cobb angle changed from 53.2° to 39.4° and the lumbar Cobb angle changed from 50.2° to 47.6°.(3)It is concluded that both orthopedic modalities provide improvement in the degree of scoliosis,with the thoracic correction being greater than the lumbar correction.Also,the asymmetric stress distribution on the concave and convex sides is improved,which contributes to normal bone growth.A vertical distraction approach is appropriate for larger Cobb angles,and a lateral thrust approach is appropriate for smaller Cobb angles.The results of this study help to understand the mechanism of spinal orthosis and provide a theoretical basis for the choice of orthopedic approach.

Objective To investigate the effect of subanesthetic dose of esketamine on emergence agitation(EA)in patients undergoing laparoscopic hernia repair.Methods Seventy-two male patients who treated with lapa-roscopic hernia repair under general anesthesia were randomly divided into AS group(subanesthetic esketamine)and control group.In the AS group,0.2 mg/kg of esketamine was administered intravenously 30 minutes before the surgery ended,while the control group was given an equal volume of normal saline.Upon surgery completion,patients were transferred to PACU with endotracheal tube retained,and the time to extubation was recorded.Hemo-dynamic parameters were measured immediately after extubation and at 10 min,30 min,1 h,and 4 h thereafter.Patients' pain and sedation levels were assessed at the above time points using RASS and VAS,respectively.The incidence of EA was evaluated using the Confusion Assessment Method for the Intensive Care Unit(CAM-ICU).Observation duration in the PACU and recovery outcomes within 24 hours postoperatively were assessed via the QoR-40 and adverse events were recorded.Results Compared to those in the control group,patients in the AS group had higher HR and MAP at 10 min post-extubation,and the changes in HR and MAP over time were more stable(P<0.05).The RASS and VAS scores in the AS group were significantly lower than those in the control group at the time of extubation and all subsequent time points(P<0.05),both groups showed temporal changes in RASS and VAS scores(P<0.05),but the change process in the AS group was more stable(P<0.05).Postoperative extubation time,PACU observation duration,and adverse event rates(delirium,respiratory depression,nausea and vomiting)did not differ significantly between the two groups(P>0.05),while recovery quality was markedly better in the AS group(P<0.05).Conclusion Subanesthetic esketamine effectively alleviates pain and the incidence of EA,supports hemodynamic stability during PACU stay,and enhances recovery quality in patients undergoing laparo-scopic hernia repair,demonstrating clinical value.

Objective To investigate the effect of subanesthetic dose of esketamine on emergence agitation(EA)in patients undergoing laparoscopic hernia repair.Methods Seventy-two male patients who treated with lapa-roscopic hernia repair under general anesthesia were randomly divided into AS group(subanesthetic esketamine)and control group.In the AS group,0.2 mg/kg of esketamine was administered intravenously 30 minutes before the surgery ended,while the control group was given an equal volume of normal saline.Upon surgery completion,patients were transferred to PACU with endotracheal tube retained,and the time to extubation was recorded.Hemo-dynamic parameters were measured immediately after extubation and at 10 min,30 min,1 h,and 4 h thereafter.Patients' pain and sedation levels were assessed at the above time points using RASS and VAS,respectively.The incidence of EA was evaluated using the Confusion Assessment Method for the Intensive Care Unit(CAM-ICU).Observation duration in the PACU and recovery outcomes within 24 hours postoperatively were assessed via the QoR-40 and adverse events were recorded.Results Compared to those in the control group,patients in the AS group had higher HR and MAP at 10 min post-extubation,and the changes in HR and MAP over time were more stable(P<0.05).The RASS and VAS scores in the AS group were significantly lower than those in the control group at the time of extubation and all subsequent time points(P<0.05),both groups showed temporal changes in RASS and VAS scores(P<0.05),but the change process in the AS group was more stable(P<0.05).Postoperative extubation time,PACU observation duration,and adverse event rates(delirium,respiratory depression,nausea and vomiting)did not differ significantly between the two groups(P>0.05),while recovery quality was markedly better in the AS group(P<0.05).Conclusion Subanesthetic esketamine effectively alleviates pain and the incidence of EA,supports hemodynamic stability during PACU stay,and enhances recovery quality in patients undergoing laparo-scopic hernia repair,demonstrating clinical value.

BACKGROUND:The asymmetrical biomechanical environment of adolescent idiopathic scoliosis can lead to further wedge deformation of the vertebral body,which may affect cardiopulmonary function and compress nerves in severe cases.Adolescent idiopathic scoliosis with different degrees of scoliosis should be treated with exercise,bracing,and surgery.However,the mechanical mechanism of selecting an orthopedic approach remains unclear due to the individual variability of patients.OBJECTIVE:To investigate the biomechanical mechanism of different orthopedic modalities for the treatment of adolescent idiopathic scoliosis to provide a basis for clinical selection of treatment modalities based on the spine model of adolescent idiopathic scoliosis patients.METHODS:Based on the CT images of an adolescent idiopathic scoliosis patient,a scoliosis model(C7-L5)was reconstructed in Mimics software in three dimensions,and lateral thrust force was applied at the T8/T9 thorax and vertical distraction force was applied over the C7 vertebra with the magnitude of 20,40,60,80,100,and 120 N.The intervertebral disc stress and vertebral displacement in concave and convex sides,and Cobb angle of the spine were analyzed under two orthopedic modalities.RESULTS AND CONCLUSION:(1)With lateral thrust,there was no significant change in the C7T1-T7T8 intervertebral disc.The concave and convex stress of T7T8-L4L5 segment decreased first and then increased with the increase of lateral thrust force.The correction effect of lateral thrust on the segment near T8T9 was obvious and weakened with the extension of the segment to the cephalic and caudal ends.At 120 N of lateral thrust,the thoracic Cobb angle changed from 53.2° to 32.5° and the lumbar Cobb angle changed from 50.2° to 43.9°.(2)With the vertical distraction,the thoracic intervertebral disc stresses first decreased and then increased,and all the lumbar disc stresses decreased.The C7 displacement was the most obvious,and the correction effect gradually diminished with the segment extended to the caudal end.At a vertical distraction force of 120 N,the thoracic Cobb angle changed from 53.2° to 39.4° and the lumbar Cobb angle changed from 50.2° to 47.6°.(3)It is concluded that both orthopedic modalities provide improvement in the degree of scoliosis,with the thoracic correction being greater than the lumbar correction.Also,the asymmetric stress distribution on the concave and convex sides is improved,which contributes to normal bone growth.A vertical distraction approach is appropriate for larger Cobb angles,and a lateral thrust approach is appropriate for smaller Cobb angles.The results of this study help to understand the mechanism of spinal orthosis and provide a theoretical basis for the choice of orthopedic approach.

BACKGROUND:Ankylosing spondylitis is a progressive inflammation of spinal stiffness deformity caused by tissue ossification and fibrosis.The posture of ankylosing spondylitis patients is abnormal and their activities are limited that minor injuries can lead to thoracolumbar fractures.Traditional medical image observation limits doctors'preoperative decision planning and postoperative disease prevention for ankylosing spondylitis treatment. OBJECTIVE:Based on the spinal model of ankylosing spondylitis patients before and after posterior spinal cancellous ossification osteotomy("Y"osteotomy for short),to explore the biomechanical changes of"Y"osteotomy and fixation in the treatment of ankylosing spondylitis. METHODS:Based on the preoperative and postoperative CT images of an ankylosing spondylitis patient who went to the Second Affiliated Hospital of Inner Mongolia Medical University,a three-dimensional spine model(T11-S1)before and after"Y"osteotomy(L3 osteotomy)was reconstructed in Mimics 19.0 software.A 7.5 Nm torque was applied to the top of T11 vertebral body to simulate the movement of the spine under six conditions:flexion,extension,left bending,right bending,left rotation and right rotation.Finally,the range of motion of each vertebral body,the stress of each intervertebral disc,and the stress of the screw rod system were simulated. RESULTS AND CONCLUSION:(1)After"Y"type osteotomy and posterior fixation,the range of motion of all vertebrae in the spine decreased,and the loss rate of upper vertebrae was large(L1:77.95%).(2)The maximum stress of the spinal intervertebral disc before operation occurred at the L1-L2 segment(0.55 MPa),and the maximum stress of the spinal intervertebral disc after operation occurred at the T11-T12 segment(0.50 MPa),and the stress of intervertebral disc below T12 was far less than that before operation.(3)The maximum stress of the screw rod system(166.67 MPa)occurred in the upper and middle segments of the rod body and the root of the pedicle screw.(4)In conclusion,the"Y"type posterior fixation operation enhances the stability of the spine and reduces the range of motion of the spine.The vertebral body decompression of the fixed segment is great and the stress-shielding phenomenon of the lower vertebral body is significant.The stiffness of the rod body and the stress concentration area of the pedicle screw should be strengthened to avoid the fracture of the rod caused by stress fatigue.

A pulse and respiration synchronous detection system is designed to explore the changes of physiological signals in different situations.The system obtains the corresponding signal through STM32 control pulse and respiratory acquisition circuit,calculates and displays real-time parameters such as heart rate and respiratory rate,and transmits the data to the upper computer for storage in the database.The experimental test results show that the system can monitor pulse and respiratory waveform in different situations,and the waveform is in good condition.Compared with medical pulse oximeter,the error of measured heart rate and blood oxygen concentration is less than 3%,and the error of respiratory rate is less than 5%compared with the actual value,which verifies the accuracy of system signal acquisition.The system is small in size,low in cost,and comfortable to wear,and can be applied in experimental research related to pulse and respiratory signals.

In recent years， neurotoxicity caused by traditional Chinese medicine （TCM） has frequently occurred and has become one of the important factors restricting the development and application of TCM. TCM contains active components and its dosage-effect relationship is the key to determine its pharmacological activity and toxic effects. Among them， the endogenous toxic components include alkaloids， glycosides， diterpenoids， animal and plant toxic proteins and heavy metals， and so on； exogenous toxic components mainly refer to some harmful elements and pesticide residues during the cultivation， processing， transportation and storage of medicinal materials that are not synthesized by themselves. Effect on the processes such as oxidative stress， inflammation， ion exchange， and energy metabolism may be important mechanisms of TCM-induced neurotoxicity. Neural cells， myelin cells， axons and neurotransmitter systems are common targets of TCM-induced neurotoxicity. In the future， we can use modern research methods and big data mining means to establish a safety evaluation mode of “toxic symptoms-poisoning dose-toxic original agent-detoxification scheme” with the basic component group of toxic substances as the core， so as to provide support for development and clinical intervention of neurotoxic traditional Chinese medicine.

In this study, a surface electromyography (sEMG) and blood oxygen signal real-time monitoring system is designed to explore the changes of physiological signals during muscle fatigue, so as to detect muscle fatigue. The analysis method of sEMG and the principle of blood oxygen detection are respectively introduced, and the system scheme is expounded. The hardware part of the system takes STM32 as the core. Conditioning module composition; blood oxygen signal acquisition is based on near infrared spectroscopy (NIRS), specifically including light source, light source driving, photoelectric conversion, signal conditioning and other modules. The system software part is based on the real-time uC/OS-III software system. The characteristic parameters of sEMG were extracted by isometric contraction local muscle fatigue experiment; the relative changes of oxyhemoglobin (HbO₂) and deoxyhemoglobin (Hb) were calculated in the forearm blocking experiment, thereby verifying that the system collects two signals effectiveness.
Muscle, Skeletal ; Oxygen ; Electromyography ; Muscle Fatigue/physiology* ; Computers