Ultrasonography is considered as the preferred imaging method in diagnosis of thyroid nodules,which can quickly locate thyroid nodules and assess the size,shape,internal structure,echo level of thyroid nodules and surrounding lymph nodes.New technology of elasticity imaging and CEUS can respectively evaluate the hardness and blood supply of thyroid nodules,being helpful to nature diagnose of nodules.The progresses of ultrasound in diagnosis of benign and malignant thyroid nodules were reviewed in this article.

Objective To investigate the effect of lipid encapsulated 1,1,2-trichlorotrifluoroethane phase change nanodroplets for high intensity focused ultrasound (HIFU) ablation.Methods The lipid encapsulated 1,1,2-trichlorotrifluoroethane phase change nanodroplets was prepared with membrane hydration method,and its physicochemical properties were examined.The synergistic effect of HIFU ablation was verified with experiments in vitro and in vivo experiments.For in vitro experiment,the isolated bovine liver tissues were irradiated with HIFU (250 W,10 s,continuous wave).For in vivo experiment,the livers of New Zealand rabbits were irradiated with HIFU (200 W,5 s,continuous wave).The volume of coagulative necrosis,energy efficiency factors (EEF) and the volume of the hyperechoic area after HIFU radiation were measured.And the statistical analysis was performed.Results Phase change nanoparticles were spherical in solution and uniform in size.For in vitro experiment,the coagulative necrosis volume,EEF and hyperechoic area of bovine liver tissue injected with nanodroplets were significantly higher than those of untreated bovine liver tissue (t=28.80,19.55,14.30;P=0.01,0.02,0.02) after HIFU.For in vivo experiment,the coagulative necrosis volume,EEF and hyperechoic area of rabbit liver tissue injected with nanodroplets were significantly higher than those of untreated rabbit liver tissue (t=9.41,13.52,15.67;P=0.02,0.01,0.01) after HIFU.Conclusion The lipid encapsulated 1,1,2-trichlorotrifluoroethane phase change nanodroplets can significantly improve the efficiency of HIFU ablation significantly.

Objective To explore the application value of contrast-enhanced MRI and curved planar reformation (CPR) in diagnosis of facial neuritis.Methods Contrast-enhanced MRI scans were performed on 30 patients with facial neuritis.The involvement of intracranial facial nerve was observed,and the signal intensity of facial nerve and adjacent temporal lobe was measured with GE AW 4.5 workstation.While the signal intensity ratio (SIR) between facial nerve and adjacent temporal lobe was calculated.CPR of facial nerve was done with Philips EBW workstation,in order to observe the whole course and involvement of facial nerve.Results Among the 30 patients,SIR of affected geniculate ganglion,tympanic segment,labyrinthine segment,internal auditory meatus segment and mastoid segment was 1.59±0.28,1.16±0.16,1.38±0.20,1.30 ±0.19 and 0.96±0.14,respectively.While SIR of the relevant segment in contralateral side was 1.08±±0.19,0.74±0.13,0.81±0.13,0.83±0.08 and 0.69±0.12,respectively.There were significant differences of SIR between the affected and the contralateral segments (all P＜0.001).CPR could display the involved location and facilitate visualizing the whole course of facial nerve clearly.Conclusion Contrast-enhanced MRI and CPR are helpful to facilitate visualizing the whole course of facial nerve and clearly reveal the involvement.

Objective To investigate distribution of carotid plaques,degree of stenosis and risk factors of unstable plaques in patients with acute ischemic stroke.Methods Totally 909 patients with acute ischemic stroke (AIS group) confirmed with head MRI were enrolled,while 885 patients without stroke in the same period hospitalization were selected as controls (control group).The distribution of carotid plaques and the degree of stenosis were compared between the 2 groups.Patients in AIS group were divided into stenosis rate ≥50％ subgroup and ＜50％ subgroup according to the degree of carotid artery stenosis,and the detectable rate of stable plaques and unstable plaques were compared between the 2 groups.Clinical data of patients with unstable plaques and non-unstable plaques in AIS group were compared.Logistic regression models were established with parameters with significantly differences among those features.Results The detectable rates of multiple plaques and unstable plaques of carotid artery and the degree of stenosis in AIS group were statistically higher than those in control group (all P＜0.001).The detectable rate of unstable plaque in carotid artery stenosis rate ≥50％ group was statistically higher than that in stenosis rate ＜50％ group (P＜0.001).Age,male,diabetes,dyslipidemia,smoking and drinking were significantly risk factors (all P＜0.05).Age,diabetes,dyslipidemia and smoking were independent risk factors (all P＜0.05).Conclusion Carotid unstable plaque and stenosis are closely related to the occurrence of AIS.Age,diabetes,dyslipidemia and smoking are independent risk factors for carotid artery plaque.

Objective To explore the influence of different initial intimal tear positions on abdominal branch perfusion in Stanford B aortic dissection.Methods CTA data of 130 patients with Stanford B aortic dissection were reviewed retrospectively.The involved aortic branches (celiac trunk,superior mesenteric artery,bilateral renal artery) were classified into different types according to the degree of ischemia and perfusion damage,and their relationship with different initial intimal tear positions were also analyzed.Results There were 542 branches in 130 patients,in which 465 branches (465/542,85.79％) were ischemic,including 337 branches (337/542,62.18％) of dynamic ischemia and 128 branches (128/542,23.62％) of static ischemia,77 branches (77/542,14.21％) without ischemia.In ischemic branches,the perfusion in 69 (69/542,12.73 ％) of them were impaired and those of the other 396 branches (396/542,73.06 ％) were unimpaired.In all of the 69 branches of impaired perfusion,37 branches (37/69,53.62％) were dynamic ischemia and 32 branches (32/69,46.38％) were static ischemia,and the difference was no statistically significant (x2 =3.077,P =0.215).Furthermore,no significant impact was found in initial intimal tear positions on ischemic patterns (dynamic and static) or perfusion patterns (unimpaired and impaired;x2 =1.352,0.776,P=0.509,0.678).Conclusion Initial intimal tear positions has no significant impact on ischemia pattern or perfusion pattern of abdominal aortic branches.The evaluation of abdominal aortic branches is helpful for guiding surgery.

Ultrasonography can clearly show pelvic anatomic structures,as well as the location and length of mesh after pelvic floor reconstructive operation.The consistency of ultrasonic diagnosis of severe pelvic organ prolapse with pelvic organ prolapse quantitation is good.Furthermore,ultrasonography can provide imaging basis for evaluating the safety and efficacy of pelvic floor reconstruction.The progresses of ultrasound in diagnosis of severe pelvic organ prolapse and postoperative evaluation of pelvic floor reconstruction were reviewed in this article.

Objective To propose a novel preoperative planning method for laparoscopic ultrasound-guided implantation of I125 seeds in treating pancreatic cancer based on CT images,and to evaluate the feasibility of this treatment.Methods CT images of a pancreatic cancer patient were transmitted into the treatment planning system (TPS) developed by our laboratory,to obtain three-dimensional representations of the tumor and surrounding organs.All the positions of puncture were selected with the aid of virtual template,then possible needle paths and the number of necessary I125 seeds were planned,and the radiation dose was evaluated.Results A total of 21 needle paths with 45 seeds implantation into the tumor were planned.In the preoperative planning,the dosage parameters D90 and V100 of the tumor were 12 481 cGy and 92.83％,which was relatively eligible for the clinic requirement,whereas of suurounding non-tumor pancreatic tissue was 0 and 0.40％,respecyively.Conclusion Laparoscopic ultrasound-guided implantation of I125 seeds can be considered as a useful method for treating pancreatic cancer with accurate implantation of 125I seeds and satisfying effect of local control for the tumor in theory.

Objective To investigate the value of conventional ultrasound and CEUS in diagnosis of thyroid nodules with Logistic regression models.Methods A total of 218 cases of thyroid nodules (74 cases of malignant,144 cases of benign nodules) confirmed by pathology were enrolled.The boundary,morphology,anteroposterior and transverse diameter ratio,microcalcification,internal echogenicity,blood distribution and enhanced pattern of nodules were observed and analyzed with univariate analysis.The Logistic regression model was established with parameters which were significantly different of those features,and the receiver operating characteristic curves (ROC) were constructed.Results Hypoechoic,irregular morphology,blurred boundary,anteroposterior and transverse diameter ratio≥ 1,microcalcifications,blood distribution (Ⅰ,Ⅱ),heterogeneous enhanced pattern and low enhanced were significantly prognostic factors (all P＜0.01).Irregular morphology,microcalcifications,heterogeneous enhanced and low enhanced were independent prognostic factors (all P＜0.05).The accuracy of Logistic regression model was 82.57％,and the area under ROC curve was 0.906.Conclusion The Logistic regression model of boundary,morphology,anteroposterior and transverse diameter ratio,microcalcifica tions,internal echogenicity,blood distribution and enhanced pattern can help to diagnose malignant thyroid nodules.

Objective To investigate ultrasonographic manifestations of IgG4 positive Hashimoto thyroiditis.Methods Ultrasonographic and clinical features of histopathologically proved Hashimoto thyroiditis in 72 patients were retrospectively analyzed.The patients were divided into IgG4 positive group (n=19) and IgG4 negative group (n=53) according to immunohistochemical staining results.Echotexture,nodules,blood flow distribution and function status of thyroid were compared between the two groups.Results There were statistically significant differences in thyroid hypoechogenicity,linear echogenic strands and combined carcinomas (all P＜0.05),while no statistically significant differences in nodule number,blood flow distribution nor function status of thyroid between the two groups were found (all P＞0.05).Conclusion Ultrasonography can provide valuable imaging evidences for clinical diagnosis of IgG4 positive Hashimoto thyroiditis.

Objective To explore the value of retrograde recanalization technique in treatment of TASCⅡ C/D femoropopliteal arteriosclerosis obliterans.Methods Totally 36 patients with TASCⅡ C/D femoropopliteal arteriosclerosis obliterans were retrospectively analyzed.Preoperative and postoperative ankle brachial index (ABI) and intermittent claudication were compared,as well as postoperative vascular patency rate and complications were analyzed.Results The retrograde recanalization technique were successfully performed in all 36 patients.The walking distance and ABI of 7 days,and 3,6,12 months postoperation were increased significantly compared with preoperation (all P＜0.05).The postoperative vascular patency rate of 3,6 and 12 months was 97.22％,91.67％ and 72.22％,respectively.There was no death nor amputation during the follow-up period,and the incidence of perioperative complications was 11.11 ％ (4/36).Conclusion Retrograde recanalization technique can be used to treat TASC Ⅱ C/D femoropopliteal arteriosclerosis obliterans when anterograde access failed.