Objective To evaluate the capability of SSH/RAD MRH based on SENSE to show gastrointestinal tract anatomic structure,to provide normal anatomic base for gastrointestinal tract disease diagnosis with SSH/RAD MRH and to explore the new examination method for imaging diagnosis in gastrointestinal tract disease.Methods There were 30 healthy volunteers in total including 19 male cases,11 female cases,the age ranging from 20 to 50 with the mean age as 35 year old.All volunteers were asked to drink tap water about 1000-1500mL continuously at 60 minute before examination,to drink tap water 500mL at 20 minute before examination and receive injection of 654-2 10mg in muscle at 10min before examination.MRH were performed by Philips Gyroscan Intera 1.5T superconduct MRI scanner,using SENSE technique,phased-array coil and breath hold.SSH/RAD MRH was performed after the routine abdominal MR scan was done.Results SSH/RAD MRH was successfully performed on all volunteers at one time,and the examination achievement ratio was 100%.All images were evaluated by two senior doctors using blindness method.The ratio of the good-optimal quality images was 93% and the poor-quality images was 7%.Of all images,the stomach manifestation ratio was 65%,the stomach mucous clear manifestation ratio was 80%,the duodenum manifestation ratio was 80%,the jejunum manifestation ratio was 59%,the jejunum diameter was 2-2.5cm,the ileum manifestation ratio was 21%,the ileum diameter was 1.5-2.5cm and the small intestinal mucous clear manifestation ratio was 67%;the colon manifestation ratio was 10% and the colon mucous clear manifestation was 6%.Conclusion SSH/RAD MRH based on SENSE can clearly show the outline and mucous of the stomach,duodenum and jejunum,but can not clearly show the outline and mucous of ileum and colon.The imaging examination that the colon SSH/RAD MRH combined with the routine abdominal MR scan could clearly and conveniently show the anatomical characteristics of gastrointestinal tract.It is a new imaging examination method for gastrointestinal tract examination.

Objective To establish the database of diameter and length of the pulmonary artery branches in different phase of cardiac cycle in healthy adult chest MDCT.Methods Normal enhanced chest MDCT with ECG-gating was selected and slab thin slice maximaun intensity projection(STS MIP) reconstruction were performed in different periods on ECG represent systole and diastole respectively.The diameter and length of pulmonary artery on the plane which showed the whole length of the aim artery were measured.Doppler UCG with ECG-gating was performed in healthy adults to measure the inner diameter of pulmonary trunk and right and left pulmonary artery in different phases of the cardiac cycle as contrast method.Results Normal enhanced chest MDCT with ECG-gating showed the diameter in systole period of the main pulmonary artery was larger than that in diastole period,while it went conversely to that of the proximal part of two pulmonary arteries,distal part of the right pulmonary artery,right media-lobe artery,both S10 segmental arteries and the difference were statistic significantly,only the length in diastole period of the right upper lobe artery was larger than that in systole period.The distance between the measured point of the main artery and the right one showed larger in diastole than systole period.On ECG-gating UCG,in addition to that the diameter change of the main pulmonary artery during the two periods were coincident with MDCT,the two pulmonary artery had no significant difference during the two periods.Conclusion It is necessary using branching geometry data of the main artery to segmental arteries in different period of the cardiac cycle with normal enhanced chest MDCT for flowing model building of pulmonary artery.

Objective To compare the diagnostic efficiency in showing the responsible blood vessels for neurovascular compression in patients with trigeminal neuralgia by 3D‐FIESTA‐C and 3D‐TOF‐MRA sequences .Methods The imaging data of 60 patients with primary trigeminal neuralgia were analyzed retrospectively .After MRI examination ,all of the patients underwent micro‐vascular de‐compression (MVD) .3D‐TOF‐MRA and 3D‐FIESTA‐C sequences were performed to evaluate the three‐dimensional relationship be‐tween trigeminal nerve and blood vessels through the original and reconstructed image .The intraoperative endoscopic findings were set as the gold standard comparing to the manifestations of 3D‐TOF‐MRA and 3D‐FIESTA‐C .Results The sensitivities of 3D‐TOF‐MRA and 3D‐FIESTA‐C for the diagnosis of the existence of responsible vessels were 85 .7% ,89 .3% ,the specificities were 75 .0% , 100% ,and the accuracies were 85 .0% ,90 .0% ,respectively (P=1 .000) .Furthermore ,the sensitivities of 3D‐TOF‐MRA and 3D‐FIESTA‐C for the diagnosis of the existence of responsible arteries were 94 .1% ,88 .2% (P=0 .244) ,while the sensitivities of the responsible veins were 0 .00% and 88 .2% (P=0 .009) .Conclusion Both the 3D‐FIESTA‐C and 3D‐TOF‐MRA sequences can accurately deter‐mine the existence of responsible vessels in trigeminal neuralgia before surgery .3D‐FIESTA‐C sequence is superior to 3D‐TOF‐MRA for presenting the responsible veins ,which can be used as a supplemental diagnostic tool before operation .

Objective To evaluate the frequently used electrocardiographic criteria and propose a modified algorithm for differentiating typical atrioventricular node reentrant tachycardia(AVNRT)from atrioventricular reciprocating tachycardia(AVRT).Methods Twelve-lead electrocardiograms(ECGs)during sinus rhythm and atrioventricular node reentrant tachycardia(AVNRT)or atrioventricular reciprocating tachycardia(AVRT)with a narrow QRS complex were obtained from 154 patients who had received successful radiofrequency catheter ablation from Jan.2003 to Nov.2005.The ECGs of initial 104 patients were analyzed by 3 observers without knowledge of the electrophysiological diagnosis.According to these initial results,we proposed a modified stepwise ECG algorithm which used pseudo r′/S/Q waves,RP interval,and ST-segment elevation in lead aVR during tachycardia.Two observers assessed the algorithm in additional 50 patients.Results The algorithm was able to increase the overall accuracy from 77% and 79% with original algorithm to 84% and 87% with the modified algorithm,respectively.The inter-observer concordance was 85%.The intra-observer concordance was 89% in both investigators.Conclusion The modified algorithm can improve the accuracy of differential diagnosis between typical AVNRT and AVRT via concealed accessory pathway.

Objective To show the feasibility and value in the diagnosis of airway obstruction and pulmonary embolism with MR oxygen-enhanced ventilation combined with pulmonary perfusion imaging. Methods Eight canines were implemented for peripheral pulmonary embolism by intravenous injection of gelfoam granules at pulmonary segmental arterial level, and five of them were formed airway obstruction models by inserting self-made balloon catheter at second-bronchia. The oxygen-enhanced MR ventilation imaging was introduced by subtracting the images of pre- and post- inhaled pure oxygen. The MR pulmonary perfusion imaging was achieved by the first-pass contrast agent method. Moreover, the manifestation of MR ventilation and perfusion imaging was observed and contradistinguished with that of general pathologic anatomy, ventilation-perfusion scintigraphy, and pulmonary angiography. Results The manifestations of airway obstruction regions in MR ventilation and perfusion imaging were matched, but those of pulmonary embolism regions were dismatched. The defect range of airway obstruction in MR ventilation image was smaller than that in ventilation scintigraphy. The abnormal perfusion regions of pulmonary embolism were divided into defect regions and reduce regions based on the time courses of signal intensity changes. The sensitivity and specificity of diagnosis on pulmonary embolism by MR ventilation combined with perfusion technique were 75.0% and 98.1%. The diagnostic results were in good coherence with ventilation-perfusion scintigraphy and pulmonary angiography(K=0.743, 0.899). Conclusion The MR oxygen-enhanced ventilation combined with pulmonary perfusion imaging can be used to diagnose the airway and vascular abnormity in lung. This technique resembles the ventilation-perfusion scintigraphy. It can provide quantitative functional information and better spatial and temporal resolution, and possesses the value of clinical application.

Objective To probe the mechanism of Warlker-256 cell apoptosis resulted from permanent and strong magnetic field. Method The amplification, rearrangement, deletion, transcription and expression of P53 were detected in 320 rats treated by magnetic field and 80 controls, using Dot Blot of DNA and RNA, Southern and Northern blot, and immunohistochemical technologies. Results P53 is wild type in Warlker-256 cells, no amplification, rearrangement and deletion were found in either magnetic treated group or control group. The transcription and expression of P53 is significantly enhanced in the treated group versus the control(P

Acute cerebral infarction is a common disease of the central nervous system, the key of the current treatment is to restore blood flow and save ischemic penumbra .The studies have shown that good collateral circulation can reduce the infarction area, improve prognosis.Thus, an accurate and complete evaluation of collateral circulation in the early stage of disease has an important sig -nificance.The development of modern imaging techniques provides important means for the assessment of collateral circulation estab -lishment in acute stroke .In this paper, techniques and methods of the imaging examination of collateral circulation establishment in a -cute cerebral infarction and methods are reviewed, aiming to provide the basis for choosing reasonable imaging modality .

Objective To discuss the important points of rescue strategies in saving patients and related administration to minimize the medical risk of county or district hospitals. Methods The analytic method to minimize the medical risk of district and county hospitals was from clinical practice and via induction,summary and reorganization. Results and Conclusions The reasonable and effective clinical medical operative process includes,timely necessary emergency initial examinations,immediately organizing group consultation after mastering the emergency rescue procedures in various critical situations,following the newest modern treatment guidelines or professional expert consensus,treating patients with correct motivation to maximize the therapeutic effect,carrying out treatment while the diagnosis confirmed,properly communicating between doctor and patient,timely recording the medical record,improving the diagnosis and treatment capacity in cases with critical and difficult diseases step by step,correcting the errors and mistakes,immediately and effectively proceeding to crisis public relations in time.

Objective To analyze the imaging features of primary pulmonary hemangiopericytoma,and to provide a helpful method for clinical diagnosis.Methods Retrospectively analyze the CT and MRI characteristics of 3 cases with pathologically proved primary pulmonary hemangiopericytomas.Results All cases manifested as solitary massive tumors.On plain CT scans,the tumors were heterogeneous,well and sharply circumscribed.On contrast-enhanced CT scans,the tumors were apparently enhanced and the abnormally enhanced vasculars could be seen.On MRI scans,the tumors had inhomogeneous signal intensity and the vascular flowing-void effect could be seen.Conclusion Solitary tumor of massive volume,abnormally enhanced vasculars on contrast-enhanced CT and the vascular flowing-void effect on MRI are imaging features of primary pulmonary hemangiopericytomas.

Objective To study the normal anatomy and pathologic CT findings of HDL and compare the HDL dimension of two conditions.Methods 160 consecutive CT scans of the normal upper abdomen were reviewed and 19 cases of cadavers were used.Results There was no statistics differences between the cadavers and normal subjects on HDL.Conclusion The real dimension of HDL can be replaced by the measurement on CT image,CT is a accurate means of measuring HDL in vival of human being.