Review of Computer Modeling and Simulation of Spinal Thermal Ablation / 中国医疗器械杂志

Thermal ablation surgery can effectively eliminate bone tumors in the spine and meanwhile reduce damage to the human body. To realize the computer modeling and simulation of spine thermal ablation surgery, it is necessary to ensure the accuracy of both spine modeling and simulation temperature. This review summarizes the research progress of this field and analyzes the prospects from two aspects: computer modeling based on spine segmentation from medical images and simulation calculation of temperature field in ablation surgery. The research on spine segmentation has made great progress, but there are still some problems that prevent it from being applied in clinical simulation. Related research has been trying to solve the problems. For the ablation surgery of the spine, some researchers have tried ablation simulation and obtained simulation results that are relatively consistent with the actual temperature value.

Effects of puerarin on the neurocyte apoptosis and p-Akt (Ser473) expressions in rats with cerebral ischemia/reperfusion injury / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effects of puerarin (Pue) on the neurocyte apoptosis and the p-Akt (Ser473) expression in the ischemic penumbra of rats with cerebral ischemia/reperfusion (I/R).</p><p><b>METHODS</b>The 48 Sprague-Dawley rats were randomly divided into four groups, i.e., the sham-operation group, the I/R group, the Pue treatment group, and the Pue + LY294002 treatment group (Pue + LY), 12 in each group. The cerebral I/R rat model was established by Longa's suture method. Pue and Pue + specific P13K kinase inhibitor, i.e., LY294002 were administered. The score of the neurological deficit was estimated 1 h followed by 24 h reperfusion. The infarct volume was measured using TTC staining. The number of apoptotic neurons were detected using Tunel method. The expressions of p-Akt (Ser473) was detected using immunohistochemical assay, and the images were analyzed.</p><p><b>RESULTS</b>The score of the neurological deficit decreased more obviously, the number of apoptosis decreased more significantly, the expressions of p-Akt (Ser473) increased more significantly in the Pue group than in the I/R group (all P < 0.05). The score of the neurological deficit increased more obviously, the number of apoptosis increased more significantly, the expression of p-Akt (Ser473) decreased more significantly in the Pue + LY group than in the Pue group (all P < 0.05).</p><p><b>CONCLUSION</b>Pue reduced the apoptosis of neurocytes and had protective effects against cerebral I/R injury possibly through activating the PI3K/Akt signaling pathway.</p>

Morphology and hemodynamics in acute Stanford type B aortic dissection: quantification by MRI / 中华放射学杂志

Objective To analyse the flow characteristics in the true lumen and false lumen,and the relationship between the flow characteristics and the collapse degree of the true lumen using MRI.Methods Eleven patients with acute Stanford type B aortic dissection were examined by true FISP、3D CE MRA、PC cine MRI on a Siemens Sonata 1.5 T.Not only the quantitative data on the hemodynamics such as peak velocity,average velocity,average flow volume,forward volume,retrograde volume and net volume,and the area of the true lumen and false lumen can be acquired,but also the blood flow model,ie the velocity-mapping.Then we analysed the relationship between the flow characteristics and the collapse degree of the true lumen.Results The average area of the false lumen in the proximal descending aorta(about 2 cm distal to the entry)was(8.10±2.93)cm2,and(2.59±0.93)cm2 of the true lumen in the same slice (P＜0.05).The average velocity in the false lumen,(2.81±0.73)cm/s,was significantly lower than in the true lumen[(15.52±2.84)cm/s,P＜0.01],wheras the average flow(36.32±5.37)ml/s,was not significantly difierent(P＞0.05)from the average flow in the false lumen(37.62±24.58)ml/s.The velocity-mapping curve looked like same in the true and false lumen in this level.And in the abdominal aorta(about the level of the hepatic hilar),the average flow(10.46±5.57)cm/s was significantly lower(P＜0.05)than in true lumen[(4.04±2.96)cm/s].At this level,the direction of blood flow in the true lumen was retrograde(upward)in the mid and late systolic phase in six patients,and normal in the diastolic phase and early systolic phase,that was to say,bidirectional blood flow can be caught in the true lumen of the abdominal aorta.The collapse degree of the true lumen was closely correlated with the the average velocity and the flow volume in the false Iumen,and the coefficient correlation and P value were 0.931 and 0.000,0.926 and 0.000 respectively.Conclusions PC cine MRI can quantitatively measure the peak velocity,average velocity,average flow volume,forward volume,retrograde volume and net volume,and combined with 3D CE MRA can evaluate the collapse degree of the true lumen.It is important for clinical application in the diagnosis,therapeutic management and the therapeutic opportunity choice of the acute Stanford type B aortic dissection.

A Preliminary Study on Non-invasive Measurement of Intra-abdominal Pressure / 航天医学与医学工程

Objective To present a new method and design of an instrument for measuring intra-abdominal pressure (IAP) non-invasively. Method A pressure sensor (YH-4) and a displacement sensor (sliding rheostat) were assembled into a probe so that they work in a linear mode. When this assembled instrument probe acts on the abdominal wall of a subject, a pressure as called the external abdominal pressure (EAP), and a corresponding displacement were detected. A relationship was established mathematically between the IAP measured by non-invasive and invasive method, and IAP was calculated by EAP measurement indirectly non-invasively. Result The method was testified by animal experiment in rabbits. And the preliminary results indicated that linear relation between EAP and IAP was obtained. Conclusion Feasibility of the new method is validated by animal experiment. It provides scientific evidence for further clinical experiment.