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Objective:To explore the value of 70 keV virtual monoenergetic images(VMI) on dual-layer spectral detector CT in improving abdominal arterial phase images quality.Methods:The arterial phase images of patients who underwent abdominal enhanced scan on the Philips IQon dual-layer spectral detector CT in Shengjing Hospital of China Medical University from January to May 2019 were retrospectively analyzed. Fifty patients (12 males, 38 females) were included with age of 26-74 （53±12） years. Objective and subjective evaluation was performed in 120 kVp polychromatic conventional images (group CI) which derived from iterative reconstruction algorithm and group 70 keV VMI which derived from spectral reconstruction algorithm. The attenuation, noise, signal to noise ratio and contrast to noise ratio of abdominal aorta, celiac trunk, superior mesenteric artery, left kidney artery, right kidney artery, liver, spleen, pancreas, left and right kidney were compared between group 70 keV VMI and CI by using paired t test. Image quality of group 70 keV VMI and CI was evaluated by two radiologists independently with a 5-point scale and compared by Wilcoxon rank test. The inter-agreement of subjective scoring between the two radiologists was evaluated by Kappa test. Results:Except for pancreas, the attenuation of abdominal arteries and solid organs in group 70 keV VMI were higher than that of group CI and the difference was statistically significant ( Pall<0.05). The attenuation of pancreas was lower than that of group CI ( t=-3.097， P=0.003). The noise of abdominal arteries and solid organs in group 70 keV VMI showed lower values compared to group CI and the difference was statistically significant ( Pall<0.001). The signal to noise ratio as well as contrast to noise ratio of abdominal arteries and solid organs in group 70 keV VMI was higher than that of group CI and the difference was statistically significant ( Pall<0.001). Subjective image quality scores in group 70 keV VMI were higher than that of group CI and scores of group 70 keV VMI and CI were 5 (4,5) and 4 (4,5), respectively. The difference was statistically significant ( Z=-4.131, P<0.001). There was a good consistency of subjective image quality scores between two radiologists, which Kappa values of group 70 keV VMI and CI were 0.79 and 0.69, respectively. Conclusions:Compared to CI, 70 keV VMI derived from dual-layer spectral detector CT can optimize abdominal arterial phase image quality by decreasing the noise, improving the signal to noise ratio and contrast to noise ratio.
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Objective To evaluate the efficacy of superselective renal artery embolization in the treatment of iatrogenic renal hemorrhage. Methods The clinical data of 31 iatrogenic renal hemorrhage patients who had underwent superselective renal artery embolization were retrospectively analyzed. Results All patients were found to have bleeding site by contrast examination, including pseudoaneurysm in 21 cases, renal arteriovenous fistula in 3 cases, extravasation of contrast media in 4 cases, and pseudoaneurysm and renal arteriovenous fistula in 3 cases. Microcoil embolization was used in 20 patients, and microcoil embolization combined with gelatin sponge was used in 12 patients. Thirty patients got successful embolization once, and success rate was 96.8%(30/31). One patient got successful embolization in the second time. There were no serious complications and no recurrence of renal hemorrhage. Conclusions Superselective renal artery embolization in the treatment of iatrogenic renal hemorrhage has the advantages of exact hemostasis, less trauma and fewer complication, and can retain the normal renal tissue maximumly.
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Purpose To analyze the differences of CT manifestations, and to explore the disparity of drainage volume in early drainage between Klebsiella pneumoniae induced liver abscess and non-Klebsiella pneumoniae induced liver abscess. Materials and Methods 337 cases of patients whose blood culture or drainage fluid culture results were positive were divided into Klebsiella pneumoniae group (219 cases) and non-Klebsiella pneumoniae group (118 cases). CT characteristics of the two groups were analyzed, including lesion distribution, quantity, structure, texture, abscess wall thickness, enhancement character around the lesion, whether or not concurrent with thrombophlebitis or migratory infection and so on. Early drainage volume in interventional puncture drainage was observed in both groups. Results Chest CT showed that solitary, multi-room, solid, thin-walled abscesses with concurrent thrombophlebitis, migratory infection and no enhancement around tend to occur in Klebsiella pneumoniae group (χ2=4.065, 3.834, 4.682, 5.689, 5.215, 8.362, 8.407, P<0.01). Early drainage volume of Klebsiella pneumoniae group was significantly lower than that of non-Klebsiella pneumoniae group (χ2=5.863, P<0.01). Conclusion CT manifestations of Klebsiella pneumoniae induced liver abscess are solitary, multi-room, solid, thin-walled abscesses without enhancement around them, thrombophlebitis and migratory infection are common seen and drainage volume is less in early stage after interventional operation.
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Objective To systematically assess the diagnostic performance of CTA for lower extremity peripheral arterial disease (PAD) using a Meta analysis method. Methods Studies were located through electronic searching of the PubMed, EBSCO, Springer, Ovid, CNKI, Cochrane library (from the date of establishment of the databases to October 2009 ). Bibliographies of the retrieved articles were also checked. All the studies concerning the diagnosis of PAD using CTA had been searched and reviewed, and the studies with the DSA as the gold standard were adopted as eligible. Subsequently, the characteristics of the included articles were appraised and extracted. Data on accuracy of included studies were extracted for further heterogeneity exploring, statistical pooling and SROC ( summary receiver operating characteristics)analyzing using the Meta Disc 1.4 software. Results Totally 24 studies met the inclusion criteria with a total of 1096 patients. The heterogeneity was found in these studies. The pooled accuracy indicators like sensitivity, specificity, and diagnostic odds ratio (DOR) were 0.95 ( 95% CI:0.94-0.95 ), 0.96 ( 95% CI:0.95-0.96), and 471.13 (95% CI:242. 92-913.71 ), respectively. The area under of SROC curve was 0.9888 and the Q index was 0.9555. Subgroup analysis demonstrated significant difference on diagnostic performance for various CT slices (P ＜ 0.05 ). Conclusion CTA can be regarded as an effective and feasible method for PAD diagnosis and screening, based on the results of this systematic review. However,more rigorous evaluations of CTA in patients with critical limb ischemia are needed.
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Objective To assess the value of MSCT in the follow-up of patients with small hepatocelluar carcinoma(sHCC) treated with RFA. Methods Twenty-eight patients with sHCC underwent MSCT scanning 1, 3 and 6 months after RFA. Results One month after RFA, 25 tumors were completely necrotized, among which 19 presented no enhancement on dual-phase contrast CT scans and 6 showed thin ring-shaped enhancement on artery-phase contrast. Three cases with residual tumor manifested as nodular enhancement in margin of lesion. Three and 6 months after RFA, all 25 tumors, which were completely necrotized, became small and presented no enhancement. New tumors were found in the liver in 2 cases six months after RFA. Conclusion RFA is an effective therapeutic method for sHCC, and MSCT dual-phase enhanced scanning is a good way for evaluating the curative effect and follow-up.