Objective To compare the efficacy of MRI and multi-slice CT(MSCT) for characterization of liver isolation nodular lesions in cirrhosis patients .Methods A total of 64 patients with 64 lesions ,underwent MSCT and MRI .Chi-square tests were used to compare the performances of MSCT and MRI in characterization of lesions .Results The detection rate ,accuracy ,sensitivity ,spe-cificity ,positive predictive and negative predictie of MSCT and MRI were 76 .56% ,65 .31% ,37 .50% ,78 .79% ,72 .22% ,46 .15%and 87 .50% ,85 .71% ,66 .67% ,97 .14% ,82 .93% ,93 .33% respectively .There were statistical difference in accuracy ,specificity , positie predictie between MSCT and MRI (P< 0 .05) .Conclusion MRI is superior to MSCT in accuracy ,specificity ,and positive predictive for characterization of liver isolation noduler lesions .

Objective To evaluate the feasibility,technique and preliminary clinical results of the intraoperative three-dimensional (3-D) computer navigation system assisted free vascularized fibular grafting for the treatment of osteonecrosis of the femoral head.Methods From October 2010 to April 2013,14 patients (18 hips) with osteonecrosis of the femoral head were treated by free vascularized fibular graft transfer,assisted by intraoperative3-D computer navigation system.Of 18 hips,8 were classified as stage Ⅱ ;6 as stage Ⅲ,4 as stage Ⅳ according to Steinberg system.The entire procedures were visualized and guided by the 3-D navigation system,including location of optimal entry point,exploration of the field,excision of the necrotic bone tissues,and the fibular grafting transfer with vessel anastomosis.The follow-up records included the results of X-ray,the Harris score of the hip,and the complications.Results Operations of all 14 patients (18 hips) were smooth and successful with patent vessel and umcompromised grafts evidenced by ECT scan at day 7 postoperatively.Postoperative X-ray confirmed the complete eradication of necrotic focuses with surrounding calcified bone and the accurate positioning of fibular grafts.The mean follow-up period was 23.6 months (8-29 months).Harris scores significantly improved from 57.5 ± 14.5 before operations to 87.5 ±2.5 after,with 6 hips' scores classified as Excellent,and 11 as Good.X-ray obtained more than 1 year after operation suggested improvement was achieved in 15 hips.Conclusion Intraoperative 3-D computer navigation system has multiple merits in assisting free vascularized fibular grafting for the treatment of osteonecrosis of the femoral head,including clear anatomic structure,better accuracy,less damage,and reliable functional recovery,which imply it is a highly applicable approach.

s: Objective To investigate the efficacy and safety of ultrasound-guided upper-pole access percutaneous nephrolithotomy (PCNL) for the treatment of renal staghorn calculi. Methods From October 2008 to July 2012,193 cases of renal staghorn calculi treated with ultrasound-guided upper-pole access PCNL were reviewed. Among the 193 cases,74 cases were complete staghorn calculi while the other 119 cases were partial staghorn calculi, and the calculi diameter was 2. 5 to 9. 0 cm. All the 193 cases were treated through upper-pole ac-cess successfully,70 accesses were accomplished below the 12th rib,while the other 123 accesses were accomplished between the 11th adn 12th rib. Disintegration of the stone was accomplished using Holmium laser. Results The mean operative time was 70 min (45~150 min), single tract was used in 186 cases, and double tracts were used in the other 7 cases. The stone clearance rate for one session was 72. 0%(139/193),and the total stone clearance rate was 88. 1%(170/193). Transfusion was required in 6 patients, while 2 patients with signifi-cant bleeding were treated with selective renal arterial embolization. Hydrothorax occured in 4 patients, and closed thoracic drainage was re-quired in 2 of them. 20 patients had fever, and they recovered after effective antibiotic treatment. No patients had injury to the lung or other viscera. Conclusion Upper-pole access offers optimal visibility and convenience for rigid ureteroscope to achieve a high rate of stone-free status and operating time reduce. Ultrasound guided upper-pole access PCNL should be attempted in selected cases of renal staghorn stone.

Objective To studying the MR findings and pathology of peripheral small intrahepatic cholangiocarcinoma and improving the understanding of peripheral small cholangiocarcinoma with no-bile duct dilatation. Methods A retrospective analysis of 12 patients with intrahepatic peripheral cholangiocarcinoma which were confirmed by surgery and pathology, all patients were examined by abdominal MRI without and with contrast. Correlation was made with gross pathology and surgical pathological specimen. Results On T1WI, there were 4 cases of complex low signal intensity and 8 cases of low signal intensity. On T2WI, there were 8 cases of high signal intensity and 4 cases of complex high signal intensity. Enhanced MRI showed: marked nidus enhancement on arterial phase in 1 case, and the pathological diagnosis was poorly differentiated adenocarcinoma. Inhomogeneous enhancement or annular enhancement were seen in 10 cases on arterial phase, 3 of these cases showed thin annular enhancement on arterial phase, low signalintensity on portal venous phase and isointensity on delayed phase. One case showed delayed enhancement. Thick circular enhancement correlated with pathological changes of survival of tumor cells, center areas correlated with fibrous connective tissue, and a small amount of necrotic tissue. Island-like enhancement or inhomogeneous enhancement were seen in 3 cases. Corresponding pathological changes consisted of tumor tissue and a small amount of fibrous connective tissue, as well as somenecrotic tissue. In 1 case, no enhancement was seen on all three phases and pathological changes showed cystic changes, hemorrhage, necrosis, with survival tumor cells seen between cyst and normal liver tissue. Conclusions MRI scanning of peripheral small cholangiocarcinoma lacked characteristic features, but dynamic contrast-enhanced MR had certain specific findings. Due to different pathology, the fibrous tissue, necrotic tissue and survival tumor tissue components were exhibited different imaging findings.

Objective:To investigate the brain characteristics of chronic schizophrenia by voxel-mirrored homotopic connectivity (VMHC).Methods:Forty seven patients with chronic schizophrenia from Tianjin Anding Hospital and 31 healthy controls from nearby communities were included in the study. The MRI data of the subjects were collected by Siemens Skyra 3.0 T MRI.Positive and negative symptoms scale (PANSS) was used to assess the illness severity of patients with chronic schizophrenia.SPM12 was used to process the collected MRI data. DPARSF was used to calculate the VMHC values of subjects in the two groups. The independent sample t test based on SPM12 was used to compare the VMHC values of the two groups. The significant brain regions in VMHC were regarded as regions of interest (ROI), and VBM8 was used to further analyze the gray matter volume of the ROI of the two groups. Results:Compared with healthy controls, the patients with chronic schizophrenia demonstrated decreased VMHC mainly located in lingual gyrus(voxel=208, T=4.98), occipital middle occipital gyrus(voxel=156, T=3.75) and postcentral gyrus(voxel=237, T=4.36) (FDR correction, q=0.05). Compared with healthy controls, the gray matter volumes in bilateral lingual gyrus(left(0.0034±0.0008), (0.0028±0.0013), t=-2.141, P=0.037; right(0.0025±0.0006), (0.0020±0.0011), t=2.268, P=0.028) and postcentral gyrus((0.0432±0.0051), (0.0372±0.0162), t=-2.070, P=0.045) increased, but non-significant change in postcentral gyrus of the patients with chronic schizophrenia. Conclusion:The abnormal VMHC mainly locate in lingual gyrus, middle occipital gyrus and postcentral gyrus in patients with chronic schizophrenia.

Objective:To investigate the magnetic resonance imaging (MRI) features of Cryptococcus infection in central nervous system patients with acquired immune deficiency syndrome (AIDS).Methods:The retrospective study on magnetic resonance imaging (MRI) and clinical data of cryptococcal meningitis (CM) was carried out between July 2011 and March 2017.These patients had not received anti-retroviral treatment.Patients with other specific or suspicious diseases in the central nervous system were not included in the analysis.Results:A total of 39 patients were included in the analysis,with CD4 cell counts of 13.0×106/L [(0-205)×106/L],and 94.9％ (37/39) of patients with CD4 cell count ＜100×106/L.Of the 39 patients,26 patients showed abnormal MRI signals in the brain,which were most frequently involved in the basal ganglia (20/26,76.9％).The basal ganglia lesions showed dilated VirchowRobin space (VRS)/gelatinous spseudocysts (18/20,90％).Postcontrast T 1-weighted MRI revealed no significant enhancement (3/5,60％) and mild enhancement (2/5,40％).The incidence of cerebral cryptococcal granuloma were 35％ (7/20).Nineteen of 26 patients with lesions outside the basal ganglia,of which 13 patients also complicated with basal ganglia lesions.Postcontrast T1-weighted MRI revealed no significant enhancement.The incidence of cryptococcal granuloma and meningeal thickening were 15.7％ (3/19) and 26.3％ (5/19),respectively.Postcontrast T1-weighted MRI meningeal thickening revealed enhancement (5/5,100％).Conclusion:The incidence of brain MRI abnormality in AIDS complicated with central nervous system Cryptococcus infection may not be low,and the lesions are mostly located in the basal ganglia.It most frequently displays the dilated VRS/gelatinous spseudocysts.It can also be showed cryptococcal granuloma.Postcontrast T1-weighted MRI often reveals no enhancement or mild enhancement.

This study introduced a time-delay exposure system independent of the mobile digital radiography equipment. The system consisted of lithium battery, delay control circuit, micro electric motor and related auxiliary facilities. When the starting time was reached through the delay circuit, the motor pushed out the rod to squeeze the exposure button and completed the exposure. The accessories used in this system were easy to purchase and cheap. At the same time, the technology was mature and had good compatibility. The exposure success rate was high and the exposure effect was satisfactory. This time-delay exposure system had good practicability and popularization value.
Radiographic Image Enhancement ; Technology ; Electric Power Supplies