ABSTRACT
Objective To evaluate the characteristics of 99Tcm-ciprofloxacin and explore its feasibility in early detection of secondary infectious foci of severe acute pancreatitis (SAP).Methods Ciprofloxacin was labeled with 99Tcm.The labeling efficiency and radiochemical purity of 99Tcm-ciprofloxacin were calculated and its biodistribution in normal pigs was measured.The recruited baby pigs were divided into three groups:normal control group (6), non-infected group (6) and infected group (16).370-400 MBq of 99Tcm-ciprofloxacin was injected into each pig intravenously.SPECT scanning was performed at 0.5, 1,2, 3, 4 and 6 h after administration.The differences of 99Tcm-ciprofloxacin uptake among groups were calculated and the tracer activity ratio of lesion-to-background was recorded at each time point.The diagnostic value of 99Tcm-ciprofloxacin SPECT imaging for the dectection of secondary infection of SAP was assessed using histopathological results as the gold standard.Variance analysis and least significant difference test were used to analyze the data.Results Both the labehing efficiency and radiochemical purity of 99Tcm-ciprofloxacin were over 90% within 6 h.Organs with rich blood supply, such as kidney, liver and spleen were the target organs for the accumulation of 99Tcm-ciprofloxacin; while no significant uptake was found in gastrointestinal tract or normal pancreas tissue of SAP.Rapid plasma clearance and renal excretion were observed.In the infected group, the lesion was visualized at 1 h after administration.The highest radioactivity ratio of lesion-to-background (3.36 ± 0.33) was at 3 h after administration, which was significantly higher than that of the other time point ( F =99.570, P ＜0.001 ).The sensitivity, specificity, positive and negative predictive values, Youden's index (YI) and Kappa value of 99Tc%ciprofloxacin imaging were 88.2% (15/17), 83.3% (5/6), 93.8% ( 15/16), 71.4% (5/7), 0.715 and 0.667 respectively.Conclusions The biodistribution of99Tcm-ciprofloxacin is suitable for imaging infectious focus of SAP.The optimal imaging time for the detection of secondary infection of SAP is 3 h after administration, with high sensitivity and specificity.
ABSTRACT
Objective To investigate the influence of CT-guided thermochemotherapy for pig's healthy pancreas and in turn to discuss the feasibility and efficacy on pancreatic tumors.Methods 9 healthy pigs were undergone CT-guided 80℃themochemotherapy with 18 G fine meedle injecting individually of 5-Fu 750mg(10 ml)into the pancreatic tail within 2min.CT,MRI and serum analyses test were carried out as the follow up study at 1h,3rd,7th and 14th day after the procedure;since the 3rd day,3 pigs were sacrificed right after every follow up and together with comparative study between diagnostic imagings and pathologic changes. Results The pig pancreatic tail necrotic lesions appeared to be most conspicuous at the 3rd day after thermochemotherapy and shrank gradually from 7th day to 14th day.Serum amylase level reached the highest at 3rd day after the treatment and lowered down at 7th day;and near approximately normal at 14th day.The outcomings of diagnostic imagings and macroscopic pathology were in accordance.Obvious pancreatitis occurred only in one pig and all others were nearly uneventful without serious complications of pancreatitis,intestinal adhesion and mortaligy.Conclusion CT-guided themochemotherapy can induce pancreatic,focal necrosis in healthy pig but with no serious complications;and these can further more establish the foundation for clinical practiee.(J Intervent Radiol,2007,16:844-846)