Objective To investigate the alteration of peripheral tissue`s temperature of the coagulation zone of microwave ablation in brain tissue, and to provide experimental evidence for clinical application. Methods Twelve canines were treated by microwave ablation in brain tissue. Each was ablated for 180 s with microwave output power of 20 W, 30 W, and 40 W. During the operation the peripheral temperature at the distance of 0.5 cm, 1.0 cm, 1.5 cm and 2.0 cm from the ablation center was recorded respectively. The ultrasound was performed 1 hour after the operation, and then the animals were executed and the microscopic changes of the ablation lesion were observed. Results Eleven canines suffered well for the ablation, while 1 presented abnormal respiration during the operation and died 2 hours later. During the operation, the temperature of the area 0.5 cm from the center rose signiifcantly, with the maximum temperature was (96.40±1.46)℃at the power of 20 W, and 100℃at the power of 30 W and 40 W. The temperature of the area 1.0 cm from the center rose faster, with the maximum temperatures at different powers all above the 46℃. The temperature of the area 1.5 cm from the center rose slower, with the maximum temperature below 46℃at the power of 20 W and 30 W and above 46℃at the power of 40 W. The maximum temperatures of the area 2.0 cm from the center at different powers were all below 46℃. The difference of the maximum temperature at different distances (1.0 cm, 1.5 cm, and 2.0 cm from the center) was signiifcant (F=776.78, 2640.64 and 3025.53, all P<0.05). The length and width of the ablation lesion as well as the area of edema increased with the power. At the power of 20 W, 30 W, and 40 W, the length of the ablation lesion was (29.3±1.8) mm, (32.7±2.1) mm and (34.2±2.4) mm, the width was (22.5±1.5) mm, (23.7±1.7) mm and (27.1±2.0) mm, and the width of the edema zone was (2.3±0.4) mm, (2.6±0.4) mm and (2.7±0.5) mm. The differences of the length and width of the ablation lesion at different powers were signiifcant (F=11.46, 14.49, both P<0.01). The difference of the edema area at different powers was insigniifcant (F=1.94, P=0.169). Conclusions Microwave ablation is a safe therapeutic modality. However, the shorter distance from the ablation center and greater ablation power give rise to larger ablation lesion, higher maximum temperature, and faster temperature increase. Therefore, 2.0 cm from the ablation center is a safe area.

Objective To evaluate the vulnerability of carotid arteriosclerosis plaque by ultrasound real-time tissue elastography in patients with SSS-TOAST1 style cerebral infarction, and discussing the value of the technique in assessment of the clinical course after cerebral infarction. Methods There were 113 patients of SSS-TOAST1 style cerebral infarction who had carotid arteriosclerosis plaque and 48 patients of contrast group who had carotid arteriosclerosis plaque selected by ultrasound in Department of Ultrasound, Beijing Tiantan Hospital, Capital University of Medical Sciences. The results between two groups were compared. The cerebral infarction group was divided into two sub-groups according to the clinical course of patients after cerebral infarction, and the difference between them was compared. Results The size had no significant difference between cerebral infarction group and contrast group as well as between aggravated group and non-aggravated group (t=15.61, 10.77, 4.52, P<0.05). The real-time tissue elastography of carotid arteriosclerosis plaques were red-green in most patients of cerebral infarction group. The real-time tissue elastography of carotid arteriosclerosis plaques were green-blue in most patients of in control group. The value of elasticity of plaque, vessel wall and stiffness of carotid arteriosclerosis plaque between cerebral infarction group and control group had significant differences (t=15.61, 10.77, 4.52, P<0.05). The value of real-time tissue elastography between aggravated group and non-aggravated group had significant difference (t=6.39, 2.30, 3.80, P<0.05). Conclusion Real-time tissue elastography could evaluate the stiffness of carotid arteriosclerosis plaque, which was related with the vulnerability of carotid arteriosclerosis plaque. The values of elasticity of plaque, vessel wall and stiffness of carotid arteriosclerosis plaque in patients with SSS-TOAST1 style cerebral infarction were lower, and the vulnerability of carotid arteriosclerosis plaque was higher. Real-time tissue elastography had some worth in evaluating the clinical course of patients after cerebral infarction.

Objective To explore the value of contrast-enhanced ultrasonography(CEUS) in brain injuries. Methods ① Models of graded brain trauma were created in brains of 10 healthy mongrel dogs after the animals were anesthetized and the cranium were removed. Conventional ultrasonography(US) and CEUS were performed to observe the characteristics of traumatic region. ② Thirteen patients with traumatic brain injuries were collected to perform intraoperative ultrasonography. The location, depth, size, internal echo and boundary of traumatic brain injuries were clearly displayed. Eight injury sites were chosen to undergo CEUS. Results ① Twelve injury sites in brains of 10 dogs were detected,and CEUS were peformed in 10 lessions, of which 1 was diagnosed with cerebral contusion, 1 with cerebral contusion and cerebral hemorrhage, 7 with intracerebral hematoma, 2 with ventricular hematoma, 1 with blood vessels in intracerebral hematoma. ② Fifteen lesions were detected by preoperative CT scan, but 18 lessions were detected by intraoperative ultrasound. During operation epidural hematomas in 4 cases were detected. After CEUS,the area of lessions was clearly revealed to be extended, the hemorrhage area was exempt from enhancement while peripheral normal cerebral tissue was homogenously enhanced. Conclusions Conventional ultrasonography could display brain injuries. In case of accurate intraoperative encephalocele, intraoperative untrasound conduces to discover delayed intracranial hematoma. Different traumatic brain injuries had their special CEUS findings.

Objective To explore the value of the located needles guided by intraoperative ultrasound in resection of brain cavernous malformations. Methods Fourteen patients diagnosed as brain cavernous malformations confirmed by preoperative CT and MRI. Detected by the located needles under intraoperative ultrasound guidance, 14 lesions were excised. Results Intraoperative ultrasound-guided needles accurately located 14 cases of patients with brain cavernous malformations. Fourteen lesions were removed successfully. The distances between lesions and the dura mater were 1.5-2.9 cm,the sizes of lesions were 0.8-2.8 cm. Fourteen lesions by color Doppler flow imaging showed point-like blood flow. Conclusions Brain cavernous malformations can be accurately detected by the located needles under intraoperative ultrasound guidance.

Objective To study the feasibility and characteristic findings of contrast-enhancedultrasound(CEUS)on peripheral pulmonary tumors.Methods Twenty patients with peripheral pulmonarytumors proven by pathology were studied.They were divided into two groups:primary pulmonary tumors (n=15),and metastatic pulmonary tumors(n=5). The dynamic enhancement images were stored and Strip enhancement was dominant in the primary pulmonary tumors,while dot enhancement was dominant in ascended quickly and descended slowly,while ascended slowly and descended slowly in majority of metastaticThe modes of enhancement and time-intensity curves were all different in primary and metastatic pulmonary tumors.Contrast-enhanced uhrasound is promising in the diagnosis of peripheral pulmonary tumors.

Objective To study the effect of nicorandil on the function of coronary artery endothelium during hypoxiareoxygenation.Methods Forty-five fresh porcine left anterior descending coronary artery rings in 2mm long were randomly divided into five groups.Control group ( n =9):incubation in Krebs-Henseleit (KH) at 37℃ for 90 minutes with a constant supply of oxygen ; Group A ( n =9):30-minute hypoxia ( PO2 ＜ 15 mm Hg) followed by 30 minutes reoxygenation in KH at 37℃ ; Group B ( n =9):60-minute hypoxia followed by 30 minutes reoxygenation in KH at 37 ℃ ; Group C ( n =9):60-minute hypoxia followed by 30 minutes reoxygenation in KH added nicorandil ( 0.2 μmol/L) at 37 ℃ ; Group D ( n =9 ):60-minute hypoxia followed by 30 minutes reoxygenation in KH added nicorandil (0.2 μmol/L) and 5-hydroxydecanoate ( 10μmol/L) at 37 ℃.The endothelium-derived hyperpolarizing factor (EDHF) -mediated relaxation ( U46619 precontraction) induced by bradykinin in the present of indomethacin (7 μmol/L),LNNA (300 μmol/L) and oxyhemoglobin (20 μmol/L)were measured in the organ chambers.Results Compared with control group,the relaxation was significantly decreased in group A,B and D ( P ＜ 0.001 ),while there is no significant difference in group C ( P ＞ 0.05 ).Compared with group A,the relaxation was significantly reduced in group B and D (P ＜0.001 ).Conclusion Hypoxia-reoxygenation impairs EDHF mediated relaxation in coronary artery with more injury during prolonged hypoxia.This function can be restored by preconditioning with nicorandil The mechanism is mainly related to the mitochondrial ATP-sensitive K + channels.

Objective To study the effect of Perfadex and Wisconsin Unviersity solution on the function of pulmonary artery endothelium.Methods Small lobe pulmonary arteries were dissected from nine porcine lungs.The artery from each lung was cut into six rings in 2mm.Two of them were randomly incubated in Krebs,Perfadex or Wisconsin Unviersity solution (UW solution) at 4℃ for 4 hours.Endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxation (percentage of-7.5 logM U46619 precontraction) induced by bradykinin or calcium ionophone A23187 in the present of indomethacin,L-NNA and oxyhemoglobin were measured at 37 ℃ in the organ chambers.Results Vasoconstriction induced by U46619 is no significant difference among three groups (P＞ 0.05).Compared with Krebs group,the relaxation induced by bradykinin or A23187 was significantly decreased in Perfadex group (P＜0.01),while there is no significant difference in UW group (P＞0.05).Conclusion Endothelium-derived hyperpolarizing factor (EDHF) plays an important role in endothelium-mediated relaxation of porcine pulmonary artery.EDHF-mediated relaxation is impaired when the lung preserved with Wisconsin Unviersity solution,wheras its function is not affected by Perfadex solution.

ObjectiveTo study the impact of type 2 diabetes mellitus on endothelium of great saphenous vein in patients with coronary heart disease.MethodsPatients undergoing coronary artery bypass grafting were selected, 20 with type 2 diabetes mellitus (experimental group) and another 20 patients without (control group).The rings of great saphenous vein in I cm length were taken from those patients and then divided into 3 segments.The structure of endothelium was evaluated by the microscope and the changes of venous tone were measured in organ chamber at 37C with a constant supply of oxygen.Venous vasoconstriction was induced by phenylephrine (10-5 mol/L) and vasodilatation induced by nitroglycerin or acetylcholine (10-9 ～ 10-5 mol/L).ResultsMore damages of ultrastructure of the endothelium of saphenous vein were found in experimental group than in control group.There were no significant differences regarding the venous tone between the two groups (P ＞0.05) when vasoconstriction induced by phenylephrine and vasodilatation by nitroglycerin.However, the vasodilatation induced by acetylcholine was significantly decreased in experimental group than in control group (P ＜ 0.05).Conclusion Type 2 diabetes mellitus can aggravate the damage of endothelium of saphenous vein in patients with coronary artery disease.

Objective To explore the value of contrast-enhanced ultrasound (CEUS) in classifying lesions,measuring the range of lesions,and the ability of manifesting the boundary and the severity of lesions after traumatic brain injury.Methods 83 patients with traumatic brain injury underwent the emergency surgery operations were enrolled in this study.Intraoperative ultrasound was applied in detecting the echo characteristics of lesions and classifying.Traumatic brain injuries which were classified indefinitely by conventional ultrasound were examined by CEUS to observe enhanced features of trauma lesions and the surrounding tissue,confirm the types of lesions,identify the border of lesions,measure the range of lesions,and compare with conventional ultrasound,preoperative CT and operative results.The severity of lesions was judged according to the parameter of time intensity curve (TIC).The results which would help the operators to adjust the method of treatment timely was informed.Results 148 lesions were detected by intraoperative ultrasound among 83 patients in this study.Thirty-two lesions which were classified indefinitely by conventional ultrasound were examined by CEUS.The results of classifying were confirmed by CT and operations,the diagnostic accuracy rate was 100％.The absolute peak intensity was changed with the injury severity,the more serious of the tissue,the lower absolute peak intensity was displayed.The boundary of lesions was manifested clearly after CEUS.Compare to the conventional ultrasonography,the range of lesions was larger.The difference between them was meaningful significally(P =0.01).Based on the results of CEUS,the way of operation was adjusted in 21 lesions.Conclusions Using the contrastenhanced ultrasound and intraoperative ultrasound,various traumatic brain injuries can be diagnosed accurately.By CEUS,the perfusion of lesions would be displayed,which would hint the severity of the brain tissue and help the operators adjust the methods of treatment timely,and provide the reliable evidence for the operation precisely.

Objective To evaluate the value of ultrasound in assessing superficial temporal arterymiddle cerebral artery(STA-MCA)anastomosis in patients with moyamoya disease.Methods Ultrasonic Doppler studies were made pre-and postoperatively in 25 patients with moyamoya disease undergoing STAMCA anastomosis.The peak systolic velocity(PSV),end diastolic velocity(EDV),pulsatility index(PI)and resistance index(RI)were measured in external carotidartery(ECA) and superficial temporal artery (STA)pre-and postoperatively.The pattern of the collateral circulation through the bypass was categorized based on postoperative external carotid angiograms.Thus three categories were determined as extensive,moderate and poor.The patients were divided into three groups based on the pattern of the collateral circulation through the bypass,which was determined based on the angiographic findings.PSV,EDV,PI,RI of STA was compared between groups.Results ①The values of the PSV,EDV of anastomosed STA were significantly higher and the values of PI,RI were significantly lower after operation.②The values of the PSV,EDV of the anastomosed ECA tended to be higher and the values of PI,RI tended to be lower in postoperation patients,but the differences were not significant within preoperation and postoperation group.③The Values of the PSV,EDV of the anastomosed STA were significantly different among the groups.The PSV.EDV tended to be higher and the PI,RI tended to be lower in patients with more extensive bypass flow.④The blood flow direction of STA was from extracranial to intracranial.Conclusions The PSV,EDV,PI,RI of STA can predicting the extent of collateral flow through an STA-MCA bypass.Color Doppler ultrasonography is a noninvasive method of assessing the function of STA-MCA bypass in patients with moyamoya disease.