Objective To introduce a method for fast establishment of pig models with secondary hypersplenism, and using this model to study the effect of radiofrequency ablation (RFA). Methods Congestive splenomegaly was created by CT- guided percutaneous embolization of splenic vein and its collateral branches in pigs. Then radiofrequency ablation was employed in the models to observe the changes of peripheral blood as well as the spleen changes in its morphology and histopathology. The blood cell count for peripheral venous blood was determined once a week, and the spleen size was measured by CT scanning. Results One week after splenic vein embolization, the counts of peripheral erythrocytes and platelets showed a reduction, which became more obvious in three weeks (P < 0.05). Erythropenia, thrombocytopenia and splenomegaly could last for over six weeks. At the second week after the procedure , pathologically the spleen assumed passive congestion appearance. The thermal energy produced by radiofrequency ablation could cause local splenic coagulation necrosis, splenic vessels occlusion and splenic thrombotic infarction due to diffuse micro-vascular thrombosis. Conclusion To establish an animal model with secondary hypersplenism, the method of CT-guided percutaneous embolism of splenic vein is simple and reliable. The animal models can be used for surgical or interventional researches. Radiofrequency ablation is an effective intervention means.

Objective To evaluate the feasibility, effectiveness and clinical application of B ultrasound/CT-guided percutaneous radiofrequency ablation (RFA) in treating hypersplenism due to portal hypertension. Methods B ultrasound/CT-guided percutaneous radiofrequency ablation was carried out in 28 patients with hypersplenism associated with portal hypertension. Routine blood counts, liver functions and prothrombin time were determined before RFA and 2 days, 2 weeks, one, 3, 6 and 10 months after RFA separately. The results were analyzed and compared. Enhanced CT scanning reexamination was performed immediately after RFA and one week, one, 3 and 10 months after RFA separately. The volume of ablated spleen tissue was calculated with CT post-processing software. Results The mean operation time was (3.8 ± 1.1) hours and the mean ablation time was (2.7 ± 0.8) hours. The ablated volume of the spleen accounted for 20% - 80% of the whole spleen, with a mean of 50.5% ± 10.3%. Two days after RFA, the platelet count decreased to (19.5 ± 12.1) × 109/L, while the white blood cell count reached its peak value of (5.4+0.2) × 109. From two weeks to 10 months after RFA the white blood cell counts and platelet counts, the liver function, and the prothrombin time were significantly improved when compared with preoperative ones, and the differences were statistically significant (P < 0.05). Pathologically, hepatic proliferation could be seen within the cirrhotic liver after RFA. Child-Pugh score was grade A in all patients except one patient with Child-Pugh grade C who developed abdominal distention and bloody ascites after RFA. No other severe complications occurred. Conclusion For hypersplenism due to portal hypertension, B ultrasound/CT-guided percutaneous radiofrequency ablation is a safe, effective and minimally - invasive treatment.

Objective To explore the value of interventional therapy in unruptured intracranial aneurysms combined with brain arteriovenous malformations (BAVM).Methods Data of 23 patients with unruptured aneurysms combined with BAVM were retrospectively analyzed.All patients were treated with interventional embolization,and the embolization methods were choosen according to the Redekop classification.The proximal or distal hemodynamic aneurysms were embolized with coils,and the intranidal aneurysms were embolized with Onyx.The outcome was assessed by the Glasgow outcome score (GOS) one week after treatment.DSA scan was used to observe whether there was recurrence during 3-6 months after embolization.Results Totally there were 36 aneurysms in 23 patients,including 8 intranidal aneurysms,16 proximal flow-related aneurysms,11 distal flow-related aneurysms and 1 unrelated aneurysm.Embolizations of 16 proximal hemodynamic aneurysms and l0 distal hemodynamic aneurysms were done with coils.And embolization of 8 intranidal aneurysms were done with Onyx.One distal hemodynamic aneurysm was not embolized due to the difficulty of embolization and the regular shap of aneurysm;and the patient died of cerebral hernia caused by intracranial hemorrhage on the sixth day after embolization.Because it was more suitable for surgical clipping,1 unrelated hemodynamic aneurysm was not embolized.In 23 cases,BAVM were completely embolized in 7 cases and incompletely embolized in 16 cases.A week after operation,the GOS score were 5 in 19 cases and 4 in 3 cases.The GOS score was not evaluated in the dead case.Except for 1 cases of death,the other 22 cases were followed up after embolization.No recurrence and intracranial hemorrhage occurred.Conclusion Interventional treatment of unruptured intracranial aneurysms combined with BAVM is safe and effective.Making treatment plan according to the hemodynamic characteristics of lesions and completely embolizing all lesions to prevent postoperative bleeding is helpful to improve the prognosis of patients.

Objective To investigate the value of parametric imaging of CEUS in uterine fibroids with different signal intensity on T2WI by high intensity focused ultrasound (HIFU),and dynamic vascular pattern (DVP).Methods Totally 16 patients with single uterine fibroids were divided into high intensity group (n=6),isointensity group (n=4) and low intensity group (n=6) according the signal intensity on T2WI before HIFU treatment.CEUS were performed on each patient.SonoLive CAP software was used to analyze the CEUS images and DVP parametric images were reconstructed.Results The maximum intensity,rising time,time to peak and mean transit time were (235.40± 35.46)％,(22.80± 3.16)s,(25.09±2.44)s,(125.78 ± 27.63)s in high intensity group,(71.97± 2.43) ％,(24.85±3.22)s,(32.81±3.92)s,(66.52±3.48)s in isointensity group and (16.17±2.83) ％,(25.42±2.66)s,(32.82±3.76)s,(64.27±3.33)s in low intensity group.There were statistically significant differences among three groups (all P＜0.05).DVP curve was divided into two types:non-washout in high intensity group and cystic type in low intensity group.Conclusion CEUS and DVP imaging can directly quantitively display the difference of blood perfusion among the uterine fibroids with different signal intensity on T2WI which can provide important information for HIFU treatment in uterine fibroids.

Objective To evaluate clinical value of ultrasound contrast agent the sulfur hexafluoride micro-bubble in the treatment of T2WI high signal uterine fibroids with high intensity focused ultrasound (HIFU).Methods A total of 36 patients with T2WI high signal uterine fibroids were randomly divided into experimental group and control group.Eighteen patients in experimental group received HIFU treatment with sulfur hexafluoride micro-bubble before,during and after the operation while another eighteen in control group received HIFU treatment with sulfur hexafluoride micro-bubble only after the operation.We recorded operation time (min),changing time of massive gray (s),irradiation time (s),therapeutic dose (J),incidence of complications and ablation rate (％).Results Operation time,changing time of massive gray,irradiation time,and therapeutic dose in experimental group were (101.51±43.02) min,(856.42±451.14) s,(1077.37±546.23) s,and (496581.81 ± 267192.31) J,respectively while those in control group were (261.34 ± 85.53) min,(1 833.32 ± 642.67) s,(1 890.21 ± 1 268.43) s,and (784 608.31 ± 357 621.45) J,respectively.Significant differences were found among those parameters between the two groups (P ＜0.05).Tumor ablation rate in experimental group was 83.3％ while that in control group was 55.5％,which was of significant difference between the two groups (P＜0.05).One case of muscular stiffness was found in experimental group while one case of second-degree burn and two cases of muscular stiffness were found in the control group.The incidence of complications was 1/18 (5.5％).No severe complication like bowel perforation or bladder perforation was found in the two groups.Conclusion The effect of ultrasound contrast agent sulfur hexafluoride micro-bubble can shorten operation time,improve tumor ablation rate and reduce complications and it can play a guiding role in clinical work.

Objective ToinvestigatetheeffectofhighGintensityfocusedultrasound (HIFU)ablationonuterinefibroidswithdifferent withdifferentT2Gweightedimage(T2WI)signalintensity.Methods 357patientswithsymptomaticuterinefibroidstreatedwith HIFU wereretrospectivelyanalyzed.AccordingtoT2WIsignalcharacteristics,fibroidsweredividedinto4groups:hypointensity,isointensity, hyperintensityand mixedintensity.The HIFUtreatmentparametersandablationeffectsofeachgroup werecomparedby O n eG W a y analysisofvariance.Results Theaverageageofthepatientswas(38.5±6.2)y,andtherewerenosignificantdifferencesinbaseline data(P＞0.05).AllpatientssuccessfullycompletedHIFUtreatment,withtheaveragetreatmenttimeof(128.3±60.9)min,theaverage nonGperfusionvolumerate(NPVR)of(74.4±14.7)%,andtheaverageenergyefficiencyfactor(EEF)of(7.1±4.8)j/mm3.Theresults of O n eG W a y analysisofvarianceshowedthattheT2WIhypointensitygrouphadshortersonicationtime,treatmenttimeand1cm3 sonicationtime,smallertreatmentpowerandEEF,largerNPVR,comparingwiththehyperintensitygroup withstatisticallysignificant differences(P＜0.05).Conclusion UterinefibroidswithT2WIhypointensityhavelowwatercontentandhighenergydepositionefficiency, whicharemoresuitableforHIFUablation.

Objective To compare high-intensity focused ultrasound (HIFU) ablation effect on uterine fibroids between patients with different uterus positions. Methods The clinical data of 372 patients with symptomatic uterine fibroids, who were treated with HIFU at authors' hospital, were retrospectively analyzed. According to the position of the uterus, the patients were divided into anteverted group, mid-position group and retroverted group. Single factor analysis of variance was used to compare the baseline data of fibroids and HIFU ablation results between each other among the three groups. Results Successful HIFU treatment was accomplished in all patients. The average age of the patients was (39±6) years. Single factor analysis of variance indicated that no statistically significant difference in baseline data of fibroids existed between each other among the three groups (P>0.05) . The one cm3 sonication time and energy efficiency factor (EEF) in the anteverted group were significantly smaller than those in the retroverted group, the differences were statistically significant (P =0.007 and P =0.017 respectively) . Conclusion Uterine fibroids within an anteverted uterus are more likely to be ablated by HIFU.