Arteriovenous malformations(AVMs)are a kind of high-flow vascular malformation.AVMs can be classified in many ways,including histo-embryological classification,hemodynamic classification,etc.At present,the two mainstream classification systems used to guide the embolization treatment of peripheral AVMs are proposed by Cho and Yakes respectively based on the angiographic morphology of the lesions.Interventional embolization is the first-line treatment for AVMs.Among the many embolization agents,absolute ethanol is a permanent liquid embolization agent.Absolute ethanol can directly destroy the vascular endothelial cells to achieve a good curative efficacy,therefore,it has been wildly used in the treatment of peripheral AVMs.Yakes classification combines the angiographic classification with absolute ethanol embolization therapy.During absolute ethanol treatment,close attention should be paid to the occurrence of complications such as elevated pulmonary artery pressure.Although there are challenges remaining in the treatment of AVMs,the rapid development of molecular genetics has made targeted drug adjunctive treatment for AVMs possible.Perhaps,the novel therapeutic mode of combination use of traditional therapy targeted drug may be able to make a breakthrough in the treatment of AVMs.

Vascular malformations, which mainly occur in the head and neck region, are a group of congenital disorders that cannot involute and dilate gradually as patients grow. Traditional therapeutic strategies for vascular malformations include laser therapy, sclerotherapy, interventional embolization, surgical resection, etc. However, for some cases with a relatively larger range of lesions, traditional therapeutic strategies might fall short of the goals. With the development of molecular genetics, gene mutations are currently recognized as the root cause of the occurrence of vascular malformations. The progression of vascular malformation lesions is further promoted by the activation of related pathways. Low-flow vascular malformations mainly involve activation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway, whereas high-flow vascular malformations mainly involve activation of the rat sarcoma (RAS)/rapidly accelerated fibrosarcoma (RAF)/mitogen-activated protein kinase kinase (MAPKK)/extracellular-signal regulated protein kinase (ERK) pathway. Targeted drugs against relevant gene mutations and signaling pathways have also been applied in the treatment of vascular malformations, and previous studies have shown that the mTOR inhibitor rapamycin is effective and now widely used in the treatment of low-flow vascular malformations. The PI3K inhibitor alpelisib is also promising in the treatment of venous malformations, and the MAPKK inhibitor trametinib has shown good results in the treatment of arteriovenous malformations. Therefore, traditional therapies supplemented by targeted drugs may bring new breakthroughs to the treatment of vascular malformations.

Objective:To evaluate the clinical effect of embolization of congenital parotid arteriovenous fistula(AVF) using coils and absolute ethanol.Methods:From January 2015 to December 2019, 8 patients with congenital AVF in parotid region were admitted to the Department of Interventional Radiology Shanghai Ninth People’s Hospital. AVF was confirmed by angiography of common carotid artery and vertebral artery through femoral artery puncture with Seldinger technique. Using coaxial microcatheter to reach the fistula via artery or using direct percutaneous puncture to reach the dilated vein and introduced microcatheter to the fistula via puncture needle. Combined detachable coils with fiber coils, and used absolute ethanol to occlude the fistula. Then the outcome was evaluated.Results:There were 7 males and 1 female involved in this study. The average age was 28.5 years (3-58 years). All of the 8 patients were confirmed AVF in parotid region by angiography, five on the right and three on the left. The feeder artery was external carotid artery, and the outflow vein was external jugular vein. Among them, 6 patients used coaxial microcatheter to reach the fistula via artery, 2 patients used direct percutaneous puncture after failure via transarteral approach. All the 8 patients were treated with absolute ethanol, the total amount of which was 17.4 ml on average. After embolization, the external carotid angiography demonstrated that the fistula was completely occluded, the branches of the external carotid artery at the distal end of the fistula were normal, and there was no obvious reflux vein. After the operation, all the patients had no pulsation and tremor. The external jugular vein dilation disappeared in 4 patients. One patient had temporary facial paralysis on the same side of the operation area. The symptoms disappeared three days after treatment. This patient had undergone coils exposed three months after operation. After local debridement, the exposed coils were removed and the wound healed. The 8 patients were followed up for 6-12 months without recurrence.Conclusions:Embolization with coils combined with absolute ethanol is safe and affective treatment for congenital parotid AVF.

Objective:To evaluate the clinical effect of embolization of congenital parotid arteriovenous fistula(AVF) using coils and absolute ethanol.Methods:From January 2015 to December 2019, 8 patients with congenital AVF in parotid region were admitted to the Department of Interventional Radiology Shanghai Ninth People’s Hospital. AVF was confirmed by angiography of common carotid artery and vertebral artery through femoral artery puncture with Seldinger technique. Using coaxial microcatheter to reach the fistula via artery or using direct percutaneous puncture to reach the dilated vein and introduced microcatheter to the fistula via puncture needle. Combined detachable coils with fiber coils, and used absolute ethanol to occlude the fistula. Then the outcome was evaluated.Results:There were 7 males and 1 female involved in this study. The average age was 28.5 years (3-58 years). All of the 8 patients were confirmed AVF in parotid region by angiography, five on the right and three on the left. The feeder artery was external carotid artery, and the outflow vein was external jugular vein. Among them, 6 patients used coaxial microcatheter to reach the fistula via artery, 2 patients used direct percutaneous puncture after failure via transarteral approach. All the 8 patients were treated with absolute ethanol, the total amount of which was 17.4 ml on average. After embolization, the external carotid angiography demonstrated that the fistula was completely occluded, the branches of the external carotid artery at the distal end of the fistula were normal, and there was no obvious reflux vein. After the operation, all the patients had no pulsation and tremor. The external jugular vein dilation disappeared in 4 patients. One patient had temporary facial paralysis on the same side of the operation area. The symptoms disappeared three days after treatment. This patient had undergone coils exposed three months after operation. After local debridement, the exposed coils were removed and the wound healed. The 8 patients were followed up for 6-12 months without recurrence.Conclusions:Embolization with coils combined with absolute ethanol is safe and affective treatment for congenital parotid AVF.

OBJECTIVE: Differentiating unicystic ameloblastomas from keratocystic odontogenic tumors (KCOT) is necessary for the planning of different treatment strategies; however, it is difficult based on conventional CT and MR sequences alone. The purpose of this study was to investigate the utility of diffusion-weighted imaging (DWI) and apparent diffusion coefficients (ADCs) in the differentiation of the two tumors. MATERIALS AND METHODS: We prospectively studied 40 patients with odontogenic cysts and tumors of the maxillomandibular region using conventional MR imaging and DWI. ADCs were measured using 2 b factors (500 and 1000). RESULTS: Unicystic ameloblastomas (n = 11) showed free diffusion on DWI and a mean ADC value of 2.309 ± 0.17 × 10-3 mm2/s. KCOT (n = 15) showed restricted diffusion on DWI with a mean ADC value of 0.923 ± 0.20 × 10-3 mm2/s. The ADC values of unicystic ameloblastomas were significantly higher than those of KCOT (p < 0.001, Mann-Whitney U-test). An ADC cut-off value of 2.0 × 10-3 mm2/s to differentiate KCOT and unicystic ameloblastomas resulted in a 100% sensitivity and 100% specificity. Dentigerous cysts (n = 3) showed restricted diffusion on DWI and similar ADC values (1.257 ± 0.05 × 10-3 mm2/s) to those of KCOT. CONCLUSION: Diffusion-weighted imaging and ADC determination can be used as an adjuvant tool to differentiate between unicystic ameloblastomas and KCOT, although the ADC values of dentigerous cysts overlap with those of KCOT.
Ameloblastoma ; Dentigerous Cyst ; Diffusion ; Humans ; Magnetic Resonance Imaging ; Odontogenic Cysts ; Odontogenic Tumors ; Prospective Studies ; Sensitivity and Specificity

Objective To evaluate the short-term curative effect and the safety of transcatheter arterial chemoembolization (TACE) therapy by using microspheres and lipiodol for hepatocellular carcinoma (HCC).Methods A total of 87 patients with pathologically proved HCC were randomly divided into the study group (n=44,using embospheres of 100-300 μm in diameter together with lipiodol) and the control group (n=43,using gelfoam particles of 350-560 μm in diameter together with lipiodol).Postopertaive biochemical (liver function and AFP) findings and imaging (CT and/or MRI) manifestations were recorded,and the clinical efficacy and adverse reactions were analyzed.Results TACE was performed in all 87 patients.After the treatment,both the disease benefit rate and the postoperative reduction in AFP level in the study group were remarkably better than those in the control group (P＜0.05),but postoperative liver function indexes were not significantly different from the preoperative ones (P＞0.05).The average number of interventional therapy within the follow-up period of 6 months in the study group was smaller than that in the control group (P＜0.05).No statistically significant differences in 6-,12-and 18-month survival rates existed between the two groups (P＞0.05).Conclusion In treating HCC,TACE by combination use of microspheres and lipiodol is safe,its short-term curative effect is more obvious than TACE by combination use of gelfoam particles and lipiodol,and it can reduce the times of interventional procedure.Before TACE,careful planning of the pre-treatment of hepatic artery-portal vein fistula and the superselective catheterization with micro catheter should be taken into consideration.

Objective To evaluate the effect of 3D printing models applied to Medical Imaging Di-agnosis Undergraduate Teaching. Methods Students in the year 2012/2013 of Shanghai Jiao Tong Univer-sity School of Medicine stomatology specialty were chosen for this study, including 38 students in the exper-imental group (2013) and 40 students in the control group (2012). All of them were taught by the same group of teachers, including 28 core curriculum hours and 5 practice class hours. 3D printing technology with PPT was applied to the experimental group in the medical imaging diagnostic teaching, and conventional teaching including PPT and usual models in the control group. Medical students were given a test about cardiovascular system and tasked with completion of drawing hand and foot bones. Students in experimental group were also asked to complete a questionnaire about their experience. Results The questionnaire showed that 3D printing teaching molds with PPT was of great significance to improve the students interest in learning imaging anatomy, to meet the vast majority of students' learning requirements, and to achieve satis-factory results. The average scores of the circulatory system test in the experimental group were higher than that of the control group [(8.32 ±2.352) vs. (6.15 ±1.284), P<0.05)]. Students in experimental group per-formed better than students in the control group on the Locomotor system test [(6.81 ±1.347] vs. (3.84 ± 0.985), P<0.01]. Conclusions 3D printing mold combined with PPT teaching method can promote the med-ical imaging anatomy structure, learning effect and teaching quality, and has practical value in the under-graduate teaching of medical imaging diagnosis.

Objective To summarize the radiography ,CT and MRI findings of maxillary arteriovenous malformation (AVM ) . Methods Seventeen patients with maxillary AVM underwent panoramic radiography (3 patients) and enhanced MRI examination (6 patients) ,all the patient underwent enhanced CT examination .The clinical manifestation and imaging findings of maxillary AVM ,in‐cluding the location ,shape ,margin ,inner texture ,involvement of adjacent structures ,the density and signal intensity of the lesions , were analyzed .Results The lesions mainly located in molar areas (15/17) .The major clinical manifestation were repeated bleeding and acute bleeding .Other symptoms included swelling of the face ,pulsatile soft mass and anesthesia .The panoramic radiography only showed increased density .According to the change of the maxilla on enhanced CT images ,the lesions could be devided into two types :type Ⅰ ,showed intraosseous osteolytic destruction and cortical expansion (n=12);type Ⅱ ,showed“ground glass”appearance (n=5) .Bone destruction and soft tissue involvement ,widened feeding artery and draining veins ,elevated maxillary sinus were shown in all patients .External jugular vein enlargement and early enhancement (n=14) and root resorption (n= 6) were also detected . Flowing void on T1 and T2 weighted images (type Ⅰ) and hypo‐or isointense on T1WI ,hyperintense on T2WI and obvious enhance‐ment after injecting contrast material (type Ⅱ ) could observed .Conclusion Enhanced CT examination could be primarily recom‐mended and observe the extent of lesions and situation of vessels invaded of maxillary AVM .

The treatment of vascular malformations has been a difficult clinical subject. At present, the main therapeutic methods include embolization/sclerotherapy, surgical excision, laser treatment, etc. However, it is often difficult to obtain a satisfactory clinical effect. As it can induce the vascular endothelial denudation resulting in protein degeneration, ethanol embolization can obtain the effect of complete obliteration of the diseased vascular lumen. Although ethanol embolization of vascular malformations has already achieved satisfactory clinical effect, the fear of cardiac and pulmonary accidents has limited the application of this technique in clinical practice. This paper aims to make a comprehensive review concerning the effect of ethanol embolization for vascular malformations on the cardiopulmonary functions.

Based on the CT data, a medical treatment FE model of hip joint prosthesis with stepped stem was rebuilt according the anatomy of the hip joint. Under the loads of 1.5 times standard body weight (70kg), the mechanical behavior of the treatment model was calculated, and the influence of step structure and distribution for stepped stem on femur stress and stability of total hip replacement were analyzed by three-dimensional finite element analysis (3D-FEA). The results show that the step structure changs the bone stress transmission on the interface of stepped stem and femur, and benefits to reduce stress-shielding in the femur. For the same distribution of step, the reduction of stress-shielding for raised stepped stem is better than that for concave stepped stem. The raised stepped stem of which the steps is distributed one of third part of the stem is of the best effect of reduction of stress shielding in all of the analysis models, and is a beneficial mechanical design to relieves osteoporosis or osteopenia of femur caused by stress-shielding and improve the reliability of it in clinic.
Adult ; Arthroplasty, Replacement, Hip ; methods ; Biomechanical Phenomena ; Computer Simulation ; Equipment Failure Analysis ; Finite Element Analysis ; Hip Prosthesis ; Humans ; Imaging, Three-Dimensional ; Male ; Models, Biological ; Prosthesis Design ; Stress, Mechanical ; Tomography, Spiral Computed ; Weight-Bearing ; physiology