Objective： To investigate the enhancement basis and the mechanisms of solitary pulmonary nodules （SPNs） by comparing the differences in microvascular structure between benign and malignant lesions. Methods： Dynami...Objective： To investigate the enhancement basis and the mechanisms of solitary pulmonary nodules （SPNs） by comparing the differences in microvascular structure between benign and malignant lesions. Methods： Dynamic contrast-enhanced CT scan was performed on 53 patients with SPNs （diameter〈3 cm, 38 peripheral lung cancers, 5 hamartomas, 10 inflammatory lesions） using a Siemens Plus S or a Marconi MX8000 multi slices spiral CT scanner. The time-attenuation curves were interpreted. The microvascular density （MVD） and the continuity of the microvessels＇ basemental membrane in the dissected specimens were observed with the ABC （avldin-biotin complex） immuno-histochemical method in all patients. Results ：The CT enhancement values of lung cancer （49.05± 16.08 HU） and inflammatory lesions （49.59±21.30 HU） were significantly higher than those of hamartoma （8.98±4.56 HU） t=7.48, P〈0.051 t=8.35, P〈0.05）. But the enhancement of lung cancer was similar to that of inflammatory lesions （t=0.76, P±0. 05）. The time attenuation curve of inflammatory lesions tended to increase faster and reached a higher peak compared to the lung cancer, and both of them maintained a high plateau after crossing. The hamartoma showed a slight increase in the time-attenuation curve and demonstrated a lowplateau curve. The MVD of SPNs was positively correlated with CT enhancement （r=0. 8051）. The microvascular counts of peripheral lung cancer （48.45±10. 09） and inflammatory lesions （49. 60±19. 94） were significantly higher than those of hamartoma （8.70±7. 30） （t=11. 64, P〈0.001, t=6. 09, P〈0. 001 ）, but no significant difference was found between lung cancer and inflammatory lesions （t= -0.26, P=0.799）. There was no difference in the continuity of basement membrane between nodules with anen haneement less than 30 HU and those with an enhancement higher than 30HU （X^2=3. 13, P〉0.05 ）. Conclusion： The microvascular counts mainly contribute to the enhancement value of SPNs. The basement membrane is not related to nodule enhancement, but it might influence the pattern of the time-attenuation curve.展开更多
Objective: To design and test the accuracy and efficiency of our lung segmentation algorithm on thoracic CT image in computer-aided diagnostic (CAD) system, especially on the segmentation between left and right lungs....Objective: To design and test the accuracy and efficiency of our lung segmentation algorithm on thoracic CT image in computer-aided diagnostic (CAD) system, especially on the segmentation between left and right lungs. Methods: We put forward the base frame of our lung segmentation firstly. Then, using optimal thresholding and mathematical morphologic methods, we acquired the rough image of lung segmentation. Finally, we presented a fast self-fit segmentation refinement algorithm, adapting to the unsuccessful left-right lung segmentation of thredsholding. Then our algorithm was used to CT scan images of 30 patients and the results were compared with those made by experts. Results: Experiments on clinical 2-D pulmonary images showed the results of our algorithm were very close to the expert’s manual outlines, and it was very effective for the separation of left and right lungs with a successful segmentation ratio 94.8%. Conclusion: It is a practicable fast lung segmentation algorithm for CAD system on thoracic CT image.展开更多
The CT including HRCT appearances of six patients with histopathologically confirmed pulmonary alveolar proteinosis(PAP) were evaluated and compared with those of chest radiographs In all pati...The CT including HRCT appearances of six patients with histopathologically confirmed pulmonary alveolar proteinosis(PAP) were evaluated and compared with those of chest radiographs In all patients the CT manifestations were quite similar: bilateral and diffuse airspace consolidation was usually patchy or confluent with sharply defined margins, intermingled with normal lung tissue The configuration of lung lesions was “geographical” in outline with angulate, strait and curved margins There were white branching linear opacities within the ground glass background Although various pulmonary diseases may mimic PAP in some way, a full awareness of the characteristic CT appearances of PAP is helpful in achieving a correct diagnosis CT may provide more accurate evidence than chest radiograph for the evaluation of the extent and delineation of PAP展开更多
文摘Objective： To investigate the enhancement basis and the mechanisms of solitary pulmonary nodules （SPNs） by comparing the differences in microvascular structure between benign and malignant lesions. Methods： Dynamic contrast-enhanced CT scan was performed on 53 patients with SPNs （diameter〈3 cm, 38 peripheral lung cancers, 5 hamartomas, 10 inflammatory lesions） using a Siemens Plus S or a Marconi MX8000 multi slices spiral CT scanner. The time-attenuation curves were interpreted. The microvascular density （MVD） and the continuity of the microvessels＇ basemental membrane in the dissected specimens were observed with the ABC （avldin-biotin complex） immuno-histochemical method in all patients. Results ：The CT enhancement values of lung cancer （49.05± 16.08 HU） and inflammatory lesions （49.59±21.30 HU） were significantly higher than those of hamartoma （8.98±4.56 HU） t=7.48, P〈0.051 t=8.35, P〈0.05）. But the enhancement of lung cancer was similar to that of inflammatory lesions （t=0.76, P±0. 05）. The time attenuation curve of inflammatory lesions tended to increase faster and reached a higher peak compared to the lung cancer, and both of them maintained a high plateau after crossing. The hamartoma showed a slight increase in the time-attenuation curve and demonstrated a lowplateau curve. The MVD of SPNs was positively correlated with CT enhancement （r=0. 8051）. The microvascular counts of peripheral lung cancer （48.45±10. 09） and inflammatory lesions （49. 60±19. 94） were significantly higher than those of hamartoma （8.70±7. 30） （t=11. 64, P〈0.001, t=6. 09, P〈0. 001 ）, but no significant difference was found between lung cancer and inflammatory lesions （t= -0.26, P=0.799）. There was no difference in the continuity of basement membrane between nodules with anen haneement less than 30 HU and those with an enhancement higher than 30HU （X^2=3. 13, P〉0.05 ）. Conclusion： The microvascular counts mainly contribute to the enhancement value of SPNs. The basement membrane is not related to nodule enhancement, but it might influence the pattern of the time-attenuation curve.
基金the National Key Basic Research and Development Plan of China ("973" Projects, 2003CB716104)the Key Program of the National Natural Science Foundation of China (30730036)+1 种基金the Sci & Tech Planning Program of Guangdong Province (2007B010400058)the Sci & Tech Project Foundation of Guangzhou City (2007Z3-E0031)
文摘Objective: To design and test the accuracy and efficiency of our lung segmentation algorithm on thoracic CT image in computer-aided diagnostic (CAD) system, especially on the segmentation between left and right lungs. Methods: We put forward the base frame of our lung segmentation firstly. Then, using optimal thresholding and mathematical morphologic methods, we acquired the rough image of lung segmentation. Finally, we presented a fast self-fit segmentation refinement algorithm, adapting to the unsuccessful left-right lung segmentation of thredsholding. Then our algorithm was used to CT scan images of 30 patients and the results were compared with those made by experts. Results: Experiments on clinical 2-D pulmonary images showed the results of our algorithm were very close to the expert’s manual outlines, and it was very effective for the separation of left and right lungs with a successful segmentation ratio 94.8%. Conclusion: It is a practicable fast lung segmentation algorithm for CAD system on thoracic CT image.
文摘The CT including HRCT appearances of six patients with histopathologically confirmed pulmonary alveolar proteinosis(PAP) were evaluated and compared with those of chest radiographs In all patients the CT manifestations were quite similar: bilateral and diffuse airspace consolidation was usually patchy or confluent with sharply defined margins, intermingled with normal lung tissue The configuration of lung lesions was “geographical” in outline with angulate, strait and curved margins There were white branching linear opacities within the ground glass background Although various pulmonary diseases may mimic PAP in some way, a full awareness of the characteristic CT appearances of PAP is helpful in achieving a correct diagnosis CT may provide more accurate evidence than chest radiograph for the evaluation of the extent and delineation of PAP
