Imaging-guided radiofrequency ablation(RFA) is a safe and minimally-invasive interven-tional therapy with satisfactory short-term efficacy and less complications.Nowadays,RFA has been widely and successfully applied in the clinical practice for the treatment of hepatocellular carcinomas,lung cancers,adrenal malignancies,bone tumors and hypersplenism.For recent years,a combination of RFA with transcatheter arterial chemoembolization,chemical ablation or percutaneous vertebroplasty has become a new interventional therapeutic pattern for treating the tumors comprehensively,and it can be anticipated that by combining RFA with other therapeutic programs the effectiveness for tumors will be further improved.

Objective Nowadays imaging-guided nonvascular interventional procedures are becoming increasingly important in musculoskeletal field. Percutaneous interventional procedures include a broad spectrum of minimal invasive techniques, involving diagnostic and therapeutic procedures. In this article we present our views and suggestions in percutaneous musculoskeletal biopsies, percutaneous periradicular steroids infiltration, diskography, percutaneous cementoplasty, percutaneous treatment of disk herniation, and percutaneous treatment of osteoid osteoma.

Objective To evaluate the effect of interventional diagnosis and therapy in gastrointestinal hemorrhage. Methods 32 patients with gastrointestinal hemmorrhage, including 12 cases of tumor and 20 cases of vascular malformation were analized retrospectively. DSA was performed in 32 cases, barium meal radiography were undertaken in 27 cases. DSA, CTA and barium meal radiography were all performed in 13 cases. Superselective embolization was performed in 10 cases with vascular malformation. Results DSA showed clearly the radiologic features all gastrointestinal hemorrhage. Coupled DSA with CTA was reliable for diagnosis of intestinal submucosa tumor. All five cases of vascular malformation underwent successful superselective embolization showing no complication and relapse during 6 month to 2 years. Conclusions Superselective DSA and CTA are valuable methods for the diagnosis of gastrointestinal hemorrhage. Interventional embolization is an effective modarity in the treatment of gastrointestinal hemorrhage.

Radiofrequency ablation(RFA) is a local and minimally-invasive therapy.In recent years,RFA has been increasingly practiced in the clinical treatment of bone tumors.RFA is very safe and effective in relieving pain caused by inoperable metastatic bone lesions and in reinforcing the ablated vertebra when combined with bone cement injection,which is helpful in preventing pathologic fracture.RFA offers an ideal and effective alternative for patients with inoperable metastatic bone tumors.

Objective To evaluate the diagnostic value of MRI in patients with trigeminal neuralgia. Methods MR manifestations and operative results of 104 patients with trigeminal neuralgia were reviewed retrospectively. Results (1)Of 104 patients with trigeminal neuralgia,75 patients had neurovascular compression or contact of the cisternal portion of the trigeminal nerve at MR imaging and 69 patients were verified by operation;14 patients had C P angle tumors, 13 cases were diagnosed by MRI and the remaining one was verified by the operation and pathology;5 patients had vascular lesions at MR imaging which were verified by microvascular decompression.(2) The percentages of the neurovascular compression or contact,tumors and vascular lesions which were the etiologles of trigeminal neuralgia were 66 3%(69/104),13 5%(14/104) and 4 8%(5/104) respectively.(3)The sensitivity and specificity of MR diagnosis was 89 4% and 96 6% respectively.Conclusion Neurovascular compression of cisternal portion of the fifth cranial nerve is the main cause of trigeminal neuralgia.MR plays an important role in demonstrating the relationship of the fifth cranial nerve to surrounding vascular structures or tumors.

Objective To evaluate the imaging technique of magnetic resonance tomographic angiography (MRTA) in the investigation of etiology of hemifacial spasm (HFS). Methods Multiplane MRTA imaging of facial nerve of both sides was performed in all 121 HFS patients. Among them, 23 HFS patients received MVD subsequently. Results Among the 121 HFS patients, 119 patients had one side hemifacial spasm and 2 patients had double side hemifacial spasm,among them, neurovascular compression was found in the root entry zone (REZ) of facial nerve in 116 cases by MRTA,and the sensitivity was 94 3%;among the 119 cases which had no HFS,no neurovascular compression was found in the REZ of facial nerve in 112 cases by MRTA,and the specificity was 94 1%. Among 23 patients who received one side MVD, 21 patients had results that agreed with the multiplanar MRTA views. Conclusion Multiplanar MRTA was considered to be a very useful imaging technique for the study of etiology of HFS, and it also seemed to be a very important preoperative examination for MVD.

Objective To evaluate the efficacy of percutaneous CT-guided puncture and steroid injection for the treatment of lumbar intraspinal synovial cysts (LISCs).Methods A patient with clinical symptom of LISCs was undergone percutaneous CT-guided lumbar synovial cyst puncture. After aspiration of the content and steroid injection were accomplished, visual analogue scale was used to evaluate the pain of the patient before and after the treatment.Results Excellent pain relief after aspiration and steroid injection was obtained with the symptom disappearing 4 days after the treatment.Conclusions Aspiration and steroid injection can reduce the pain of the patient with lumbar intraspinal synovial cysts,and it should be the frist choice of non-surgical treatment.

Objective To identify the short and long-term therapeutic benefits of CT-guided transforaminal epidural steroid injections in lumbar spinal stenosis. Methods Thirty six patients with lumbar spinal stenosis shown by CT underwent CT-guided transforaminal epidural steroid injections because of irresponsible to conservative treatment. Patients were evaluated by visual analogue scale (VAS) before the initial injection, at 2 weeks and 1 year after the injection.Results All patients were followed up for 2 weeks and 1 year. 19 ( 52.8%) patients had successful short-term outcome, and 15 ( 41.6%) had long-term outcome. 15 ( 41.6%) patients satisfied with the short-term result and 12 (33.3%) were satisfactory with the long-term result.Conclusions CT-guided transforaminal epidural steroid injection may reduce the pain and improve the quality of life in some patients with lumbar spinal stenosis.

Objective To assess the value of enhanced MSCT scan for the Crohn's disease of small bowel.Methods Fourty-five patients of small bowel Crohn's disease who were proved by multi-methed were examined by two-phase enhanced scan with MSCT.The images were reformed in ADW 4.2 by MPR mainly.The CT values of the lesion segments in different phases were tested, with one way ANOVA in statistical analysis; the density difference between the lesion segments and normal segments in different phases were tested,the cases were divided according to 10 HU,and compared them with each other by X2 test.Results The average CT value of lesion segments was (39.3±3.7) HU in plain scan, (74.8 ± 13.8) HU in artery phase, (90.2 ± 12.3) HU in portal vein phase, there were sinigicant difference in them(F =258.87,P < 0.01).There were sinigicant difference in CT value of lesion segments between any phase and other two phases (P < 0.05).In 45 cases, there were 44 cases and one case that the difference of CT value were ≤±10 HU and > 10 HU respectively in plain scan, 6 cases and 39 cases in artery phase, 2 cases and 43 cases in portal vein phase, by X2 test, there were sinigicant difference betwwen plain scan and artery phase(X2 =32.49,P <0.01), and significant difference between plain scan and portal vein phase(X2 = 39.22,P <0.01), there were no significant difference between artery phase and portal vein phase (X2 = 1.10,P>0.05).After enhancement, the lesions can display clearly than plain scan, and the detectable rate was raised highly.Conclusion Two-phase enhancement scan can diagnosis the Crohn's disease of small bowel and evaluate it overall.

Objective To summarize the imaging features of intra-pancreatic accessory spleen (IPAS)with multidetector computed tomography (MDCT) and improve the awareness and correct diagnosis of IPAS.Methods MDCT images of seven consecutive patients with surgically and pathologically confirmed IPAS were reviewed retrospectively.The investigated features included the location,size,shape,margin,density,and enhancement of the lesions.Results Four patients were male and three were female with a mean age of 49 years old.All the lesions were located at the dorsal side of parenchyma under the capsule of pancreatic tail.Three lesions were in round-like shape,and 4 in oval shape and all were well-defined.All the lesions were mass-like without necrosis and calcification.The maximum diameter of lesion ranged from 0.9 ～ 1.8 cm with a mean value of 1.4 cm.Compared with pancreatic parenchyma,the density of lesions were homogeneous on unenhanced CT,in arterial phase,slightly increased heterogeneous density was observed in 3 patients,slightly increased homogeneous density was observed in 4 patients.All the lesions appeared as slightly increased homogeneous density in portal phase.The CT value in unenhanced phase ranged from 50 ～ 61 Hu with a mean number of 55 Hu; and it ranged from 80 ～ 110 Hu with a mean number of 97 Hu in arterial phase; and the corresponding value was from 99 ～ 120 Hu with a mean number of 102 Hu in portal phase.Among the three patients underwent MDCT angiography,neither artery nor vein was compressed or invaded,and there was no vessel connected with lesions.Conclusions IPAS has some MDCT characteristics.For small solid mass in pancreatic tail,if the density and enhancement pattern is similar to that of spleen,the diagnosis of IPAS should be considered.