Background The global outbreak of influenza A （H1N1） has led to the Ministry of Health of China listing it as one of the A-class infectious diseases. Pneumonia is the most serious complication of influenza A, common...Background The global outbreak of influenza A （H1N1） has led to the Ministry of Health of China listing it as one of the A-class infectious diseases. Pneumonia is the most serious complication of influenza A, commonly causing death. Populations are ordinarily susceptible to influenza A. This study aimed to investigate the imaging manifestation features of critical influenza A （H1 N1 ） pneumonia and to improve its diagnostic techniques. Methods A total of seven death cases from critical influenza A （H1N1） pneumonia were retrospectively analyzed on their imaging manifestations and autopsy data. Pulmonary CT scanning was performed for five cases, with one receiving additional chest X-ray and chest CT scanning, and chest postero-anterior position X-ray examination was performed for other two. Autopsy was performed for five cases and postmortem examinations were performed for other two cases. Results The seven cases of influenza A showed critical manifestations in 4-7 days after symptoms onset, with two having basic diseases of diabetes and one being pregnant. Extensive blurry high-density shadows of bilateral lungs were found in three cases, which were most obvious in middle and inferior parts of lungs. Pulmonary CT scanning revealed bilateral flaky parenchymal shadows in peripheral, dorsal and fundus segments of the middle-inferior parts of lungs, with one case of complicated pneumothorax, atelectasis and pleural effusion and another case of thin-walled cavity and dilated bronchi shadows in the superior parts of lungs. Conclusions Diagnostic imaging is an important assessing tool for critical influenza A （H1N1） pneumonia. The imaging manifestations are characteristic instead of being specific. The definitive diagnosis can be made in combination with clinical examinations and laboratory tests.展开更多
Background Colonic polyps are frequently encountered in clinics. Computed tomographic colonography （CTC）, as a painless and quick detection, has high values in clinics. In this study, we evaluated the application va...Background Colonic polyps are frequently encountered in clinics. Computed tomographic colonography （CTC）, as a painless and quick detection, has high values in clinics. In this study, we evaluated the application value of computer-aided detection （CAD） in CTC detection of colonic polyps in the Chinese population.Methods CTC was performed with a GE 64-row multidetector computed tomography （MDCT） scanner. Data of 50 CTC patients （39 patients positive for at least one polyp of ≥0.5 cm in size and the other 11 patients negative by endoscopic detection） were retrospectively reviewed first without computer-aided detection （CAD） and then with CAD by four radiologists （two were experienced and another two inexperienced） blinded to colonoscopy findings. The sensitivity,specificity, positive predictive value, negative predictive value, and accuracy of detected colonic polyps, as well as the areas under the ROC curves （Az value） with and without CAD were calculated.Results CAD increased the overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the colonic polyps detected by experienced and inexperienced readers. The sensitivity in detecting small polyps （5-9 mm） with CAD in experienced and inexperienced readers increased from 82% and 44% to 93% and 82%,respectively （P 〉0.05 and P 〈0.001）. With the use of CAD, the overall false positive rate and false negative rate for the detection of polyps by experienced and inexperienced readers decreased in different degrees. Among 13 sessile polyps not detected by CAD, two were 〉1.0 cm, eleven were 5-9 mm in diameter, and nine were fiat-shaped lesions.Conclusions The application of CAD in combination with CTC can increase the ability to detect colonic polyps,particularly for inexperienced readers. However, CAD is of limited value for the detection of flat polyps.展开更多
文摘Background The global outbreak of influenza A （H1N1） has led to the Ministry of Health of China listing it as one of the A-class infectious diseases. Pneumonia is the most serious complication of influenza A, commonly causing death. Populations are ordinarily susceptible to influenza A. This study aimed to investigate the imaging manifestation features of critical influenza A （H1 N1 ） pneumonia and to improve its diagnostic techniques. Methods A total of seven death cases from critical influenza A （H1N1） pneumonia were retrospectively analyzed on their imaging manifestations and autopsy data. Pulmonary CT scanning was performed for five cases, with one receiving additional chest X-ray and chest CT scanning, and chest postero-anterior position X-ray examination was performed for other two. Autopsy was performed for five cases and postmortem examinations were performed for other two cases. Results The seven cases of influenza A showed critical manifestations in 4-7 days after symptoms onset, with two having basic diseases of diabetes and one being pregnant. Extensive blurry high-density shadows of bilateral lungs were found in three cases, which were most obvious in middle and inferior parts of lungs. Pulmonary CT scanning revealed bilateral flaky parenchymal shadows in peripheral, dorsal and fundus segments of the middle-inferior parts of lungs, with one case of complicated pneumothorax, atelectasis and pleural effusion and another case of thin-walled cavity and dilated bronchi shadows in the superior parts of lungs. Conclusions Diagnostic imaging is an important assessing tool for critical influenza A （H1N1） pneumonia. The imaging manifestations are characteristic instead of being specific. The definitive diagnosis can be made in combination with clinical examinations and laboratory tests.
文摘Background Colonic polyps are frequently encountered in clinics. Computed tomographic colonography （CTC）, as a painless and quick detection, has high values in clinics. In this study, we evaluated the application value of computer-aided detection （CAD） in CTC detection of colonic polyps in the Chinese population.Methods CTC was performed with a GE 64-row multidetector computed tomography （MDCT） scanner. Data of 50 CTC patients （39 patients positive for at least one polyp of ≥0.5 cm in size and the other 11 patients negative by endoscopic detection） were retrospectively reviewed first without computer-aided detection （CAD） and then with CAD by four radiologists （two were experienced and another two inexperienced） blinded to colonoscopy findings. The sensitivity,specificity, positive predictive value, negative predictive value, and accuracy of detected colonic polyps, as well as the areas under the ROC curves （Az value） with and without CAD were calculated.Results CAD increased the overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the colonic polyps detected by experienced and inexperienced readers. The sensitivity in detecting small polyps （5-9 mm） with CAD in experienced and inexperienced readers increased from 82% and 44% to 93% and 82%,respectively （P 〉0.05 and P 〈0.001）. With the use of CAD, the overall false positive rate and false negative rate for the detection of polyps by experienced and inexperienced readers decreased in different degrees. Among 13 sessile polyps not detected by CAD, two were 〉1.0 cm, eleven were 5-9 mm in diameter, and nine were fiat-shaped lesions.Conclusions The application of CAD in combination with CTC can increase the ability to detect colonic polyps,particularly for inexperienced readers. However, CAD is of limited value for the detection of flat polyps.
