Diffusion-Weighted MR Imaging of Unicystic Odontogenic Tumors for Differentiation of Unicystic Ameloblastomas from Keratocystic Odontogenic Tumors

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.

TACE by using microspheres and lipiodol for the treatment of hepatocellular carcinoma: analysis of short-term efficacy / 介入放射学杂志

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.

Application of 3D printing models in undergraduate medical imaging teaching / 中华医学教育探索杂志

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.

Imaging features of the arteriovenous malformation in maxilla / 实用放射学杂志

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 effect of ethanol embolization for vascular malformations on cardiopulmonary function：recent progress in research / 介入放射学杂志

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.

Ethanol embolization of auricular arteriovenous malformations / 介入放射学杂志

Objective To present the authors' initial experience of treating auricular arteriovenous malformations (AVMs) with ethanol embolization and to assess the clinical effectiveness of this therapeutic method. Methods Twenty-two patients with AVMs were enrolled in this study. Through local puncturing or super-selective catheterization the absolute ethanol, or diluted alcohol (based on the pattern of the AVMs), was manually injected into the abnormal vascular plexus of the auricular lesion. The clinical results were estimated with physical examination or angiography at intervals of 3 ～ 4 month, and telephone questionnaire was made at monthly intervals for all patients. Results Thirty-eight ethanol embolization procedures were performed, the amount of ethanol used during the procedure ranged from 4 ml to 65 ml. After the treatment the clinical symptoms were improved, which were manifested as healing of the ulceration, stop of bleeding, disappearing or alleviation of tinnitus. Angiographic examination showed that the abnormal vascular lesion was completely vanished in 9 cases, decreased by 50% -75% in 8 cases and decreased less than 50% in remaining 5 cases. The common complications included irreversible local necrosis and vesiculation. Conclusion For the treatment of auricular AVMs ethanol embolization is an effective and safe method, which might become the therapy of first choice.

Embolization of the AVM of jaws by direct percutaneous puncture combined with endovascular route / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To report our experience to embolize the AVM of jaws by direct puncture in conjunction with endovascular treatment.</p><p><b>METHODS</b>5 cases of AVM of mandible and 2 cases of AVM of maxilla comprised this study group. The patients were embolized with coils with wool strands and PVA. The coils were placed directly into the center of the intraosseous lesion. The procedure was under the guidance of DSA machine (PHILIPS V3000).</p><p><b>RESULTS</b>The acute arterial bleeding of 4 patients was controllable. The chronic oozing bleeding in the other 3 cases disappeared in the 3 - 24 months follow-up and new bone formation was found in the follow-up radiography.</p><p><b>CONCLUSIONS</b>The embolization of the AVM of jaws by direct puncture in conjunction with endovascular therapy is effective and safe, however the longer follow-up is expected.</p>

Embolization of the high-flow vascular lesion in the head and neck by direct percutaneous puncture / 中华放射学杂志

Objective To report our experience in the embolization of the high-flow vascular lesion in the head and neck by direct percutaneous puncture. Methods Eleven cases of high-flow vascular lesion in the head and neck (8 cases of central hemangioma of the jaws and 3 cases of juvenile nasopharyngeal angiofibroma) were included in this study group. The patients of central hemangioma of the jaws were embolized with coils by a 14-gauge needle, and the fibered coils were placed directly into the center of the intraosseous AVM. The patients of juvenile nasopharyngeal angiofibroma were embolized with NBCA by a No.7 needle. The procedure was under the guidance of DSA machine (Philips V3000). Results The acute arterial bleeding in patients with central hemangioma of the jaws from the extraction of the tooth was controllable, and the pericoronal oozing of bleed disappeared in the 9-24 months follow-up. The juvenile nasopharyngeal angiofibromas were resected without blood transfusion after the embolization. Conclusion The embolization of the high-flow vascular lesion in the head and neck by direct percutaneous puncture was effective and safe, however the longer follow-up was expected.

Judicious use of ethanol embolization to improve the curative rate of vascular malformations / 介入放射学杂志

The incidence of vascular malformations is very low, and its clinical manifestations are infinite in variety, from an asymptomatic birthmark to life-threatening massive bleeding, even to congestive heart failure. The pathogenesis of vascular malformations is still unknown, therefore, its effective treatment is a real challenge. With the development of interventional technology and the accumulation of clinical experience in ethanol embolization, in local direct puncture injection and in endovascular embolization, the ethanol embolization will hopefully become the therapy of first choice for this kind of complicate and intractable disorders.

Ethanol embolization therapy for arteriovenous malformations / 介入放射学杂志

For recent years, ethanol embolization therapy has achieved satisfactory results in treating arteriovenous malformations (AVMs), which indicate that this technique will hopefully become an acceptable therapeutic form in clinical practice. It is now the preferred technique for the management of some extremely complex lesions. However, the endovascular injection of alcohol is such a work that is full of risks as weel as challenges. The ethanol embolization of AVMs may cause a series of significant complications, some of which may lead to serious outcomes. This article aims to discuss the mechanism of the ethanol embolization for AVMs, the technical principles and points, the postoperative histologic changes and the possible complications as well as their preventions.

More are awaiting for craniofacial intervention / 介入放射学杂志

The scale of craniofacial intervention lies between the fields of neuro-intervention and peripheral intervention for the main purpose to investigate,diagnose and treat the disease entities originating from or supplied by the external carotid arterial system. Patients are usually refered to the oral and maxillofacial surgery,plastic surgery and otolaryngeal surgery. Craniofacial intervention includes mainly the diagnosis and treatment with adjuvant embolization of high-flow vascular diseases,intra-arterial chemotherapy of malignant tumors,embolization of epistaxis,etc. At present,there is no consensus with regard to the diagnosis and treatment of some craniofacial diseases,therefore further investigation and discussion are needed.(J Intervent Radiol,2006,15: 321-322)

Clinical value of pre-operative double embolization for nasopharyngeal angiofibroma / 介入放射学杂志

Objective To evaluate the clinical value of pre-operative double embolization for nasopharyngeal angiofibroma. Methods Digital subtraction angiography(DSA) was carried out in 7 cases of nasopharyngeal angiofibroma. In six cases,the supplying arteries originated from the maxillary artery and the branches arising from internal carotid artery underwent double embolization-direct percutaneous puncture embolization and selective embolization of blood supplying arteries. In another case,the supplying artery originated from maxillary artery was only undertaken selective embolization for the feeding arteries. Results All the tumor masses reduced in vonlume obviously or even disappeared on the angiography after embolization. Conclusions Pre-operative double embolization for nasopharyngeal angiofibroma could be a necessary additional treatment method. (J Intervent Radiol,2006,15: 342-344)

Assessment of brain tolerance to ischemia with temporary balloon occlusion / 介入放射学杂志

Objective Attempting to find a reliable method for assessing the patient's ability to tolerate carotid artery occlusion. Methods The temporary balloon occlusion (TBO) test of carotid artery was performed for 20 patients who might have carotid artery manipulated or permanently occluded. Transfemoral artery Seldinger's catheterization was used to introduced the temporary balloon occlusion catheters into the vessels of the concern. Neurologic testing was performed continuously by the attending neurologist. Transcranial Doppler ultrasonography (TCD) and carotid artery stump pressure (SP) were measured contiuously during the TBO. The collateral circulation of Willis circle was observed with DSA. Results Out of the 20 cases, one failed during the TBO because of CCA dissection caused by catheterization, another one failed because of a neurologic defect occurring before the balloon was inflated, the others went through the test uneventfully. Two cases finished the test before the approved schedule because neurologic defects appeared 34 min and 27 min after the vascular occlusion, respectively. These two patients were proved unable to tolerate carotid artery sacrifice. The other 16 cases passed the 45 minutes TBO. Their mean velocity of ipsilateral middle cerebral artery fell 36%?18%. Their SP is (53.76?21.49) mmHg(30-87). Adequate collateral circulation in Willis circle was observed by DSA in all cases except the two who failed with the TBO. Conclusions TBO is a safe and reliable method for assessing the patient's ability to tolerate carotid artery occlusion. We suggest it should be a routine examination prior to carotid manipulations.