Objective： This study investigated the capability of dual-energy spectral computed tomography （CT） to quantitatively evaluate lung perfusion defects that are induced by central lung cancer. Methods： Thirty-two pat...Objective： This study investigated the capability of dual-energy spectral computed tomography （CT） to quantitatively evaluate lung perfusion defects that are induced by central lung cancer. Methods： Thirty-two patients with central lung cancer underwent CT angiography using spectral imaging. A univariate general linear model was conducted to analyze the variance of iodine concentration/CT value with three factors of lung fields. A paired t-test was used to compare iodine concentrations and CT values between the distal end of lung cancer and the corresponding area in the contralateral normal lung. Results： Iodine concentrations increased progressively in the far, intermediate and near ground sides in the normal lung fields at 0.60±0.28, 0.93±0.27 and 1.25±0.38 mg/mL, respectively （P〈0.001）. The same trend was observed for the CT values [-（840.64±49.08）, -（812.66±50.85） and -（760.83±89.17） HU, P〈0.001]. The iodine concentration （0.70±0.42 mg/mL） of the lung field in the distal end of lung cancer was significantly lower than the corresponding area in the contralateral normal lung （1.19±0.62 mg/mL） （t=-7.23, P〈0.001）. However, the CT value of lung field in the distal end of lung cancer was significantly higher than the corresponding area in the contralateral normal lung [-（765.29±93.34） HU vs. -（800.07±76.18） HU, t=3.564, P=0.001]. Conclusions： Spectral CT imaging based on the spectral differentiation of iodine is feasible and can quantitatively evaluate pulmonary perfusion and identify perfusion defects that are induced by central lung cancer. Spectral CT seems to be a promising technique for the simultaneous evaluation of both morphological and functional lung information.展开更多
Currently,18F-FDG coincidence SPECT(Co-SPECT)/CT scan still serves as an important tool for diagnosis,staging,and evaluation of cancer treatment in developing countries.We implemented full physical corrections(FPC) to...Currently,18F-FDG coincidence SPECT(Co-SPECT)/CT scan still serves as an important tool for diagnosis,staging,and evaluation of cancer treatment in developing countries.We implemented full physical corrections(FPC) to Co-SPECT(quantitative Co-SPECT) to improve the image resolution and contrast along with the capability for image quantitation.FPC included attenuation,scatter,resolution recovery,and noise reduction.A standard NEMA phantom filled with 10:1 F-18 activity concentration ratio in spheres and background was utilized to evaluate image performance.Subsequently,15 patients with histologically confirmed thoracic carcinomas were included to undergo a 18 F-FDG Co-SPECT/CT scan followed by a 18 F-FDG PET/CT scan.Functional parameters as SUVmax,SUVmean,SULpeak,and MTV from both quantitative Co-SPECT and PET were analyzed.Image resolution of Co-SPECT for NEMA phantom was improved to reveal the smallest sphere from a diameter of 28 mm to 22 mm(17 mm for PET).The image contrast was enhanced from 1.7 to 6.32(6.69 for PET) with slightly degraded uniformity in background(3.1% vs.6.7%)(5.6% for PET).Patients’ SUVmax,SUVmean,SULpeak,and MTV measured from quantitative Co-SPECT were overall highly correlated with those from PET(r=0.82-0.88).Adjustment of the threshold of SUVmax and SUV to determine SUVmean and MTV did not further change the correlations with PET(r=0.81-0.88).Adding full physical corrections to Co-SPECT images can significantly improve image resolution and contrast to reveal smaller tumor lesions along with the capability to quantify functional parameters like PET/CT.展开更多
To the best of our knowledge no multicenter studies have been published using standardized semi-quantitative evaluation of [123I]FP-CIT scan (DAT-SPECT). The aims of this study were: 1) to cross-compare semi-quantitat...To the best of our knowledge no multicenter studies have been published using standardized semi-quantitative evaluation of [123I]FP-CIT scan (DAT-SPECT). The aims of this study were: 1) to cross-compare semi-quantitative software-assisted evaluations of DAT-SPECTs performed in three centers with different equipments;2) to assess the accuracy of semi-quantitative evaluations of DAT-SPECT and 3) to identify the threshold with the best accuracy, sensitivity and specificity in a patient population with suspected parkinsonian syndrome. Materials and Methods: Two hundred twenty patients (mean age at the time of SPECT acquisition, 67.4 ± 9.5 yy) acquired in three centers (Ospedale San Luigi Gonzaga;Ospedale San Giovanni Battista Molinette;Ospedale Mauriziano Umberto I) were included. All of them underwent DAT-SPECT from January 2006 to July 2010. All exams were analyzed with the freely available software BASGAN and semi-quantitative data were used to predict disease. In particular, analyses were based on the values from the most deteriorated putamen and caudate, normalized for age and corrected for equipment. ROC analysis was performed and area under the curve (AUC) was estimated. Results: Analysis showed high AUCs (0.898, 0.864, 0.900 and 0.891 for each center and for the multicenter setting, respectively) confirming the very good accuracies reached. The best cut-off were 0.72 and 0.82 for putamen and caudate respectively. These thresholds allowed sensitivities and specificities in each center and in the multicenter setting of 76% and 96%, 91% and 82%, 93% and 90%, 86% and 89% respectively. No significant differences were observed between sensibility and specificity in each center. Conclusion: A unique threshold useful for all centers with high and similar sensitivities and specificities is possible after correction for age and equipments. The high accuracy reached in this multicenter trial by the semi-quantitative analysis seems similar to accuracies from qualitative analysis in other multicenter studies.展开更多
基金supported by National Natural Science Foundation of China(Grant No.81071129,30970825)the National Basic Research Program of China(973 Program)(Grant No.2011CB707705)
文摘Objective： This study investigated the capability of dual-energy spectral computed tomography （CT） to quantitatively evaluate lung perfusion defects that are induced by central lung cancer. Methods： Thirty-two patients with central lung cancer underwent CT angiography using spectral imaging. A univariate general linear model was conducted to analyze the variance of iodine concentration/CT value with three factors of lung fields. A paired t-test was used to compare iodine concentrations and CT values between the distal end of lung cancer and the corresponding area in the contralateral normal lung. Results： Iodine concentrations increased progressively in the far, intermediate and near ground sides in the normal lung fields at 0.60±0.28, 0.93±0.27 and 1.25±0.38 mg/mL, respectively （P〈0.001）. The same trend was observed for the CT values [-（840.64±49.08）, -（812.66±50.85） and -（760.83±89.17） HU, P〈0.001]. The iodine concentration （0.70±0.42 mg/mL） of the lung field in the distal end of lung cancer was significantly lower than the corresponding area in the contralateral normal lung （1.19±0.62 mg/mL） （t=-7.23, P〈0.001）. However, the CT value of lung field in the distal end of lung cancer was significantly higher than the corresponding area in the contralateral normal lung [-（765.29±93.34） HU vs. -（800.07±76.18） HU, t=3.564, P=0.001]. Conclusions： Spectral CT imaging based on the spectral differentiation of iodine is feasible and can quantitatively evaluate pulmonary perfusion and identify perfusion defects that are induced by central lung cancer. Spectral CT seems to be a promising technique for the simultaneous evaluation of both morphological and functional lung information.
基金supported by the internal research grant from China-Japan Friendship Hospital,Beijing,China(Grant No.2016-1QN-9)。
文摘Currently,18F-FDG coincidence SPECT(Co-SPECT)/CT scan still serves as an important tool for diagnosis,staging,and evaluation of cancer treatment in developing countries.We implemented full physical corrections(FPC) to Co-SPECT(quantitative Co-SPECT) to improve the image resolution and contrast along with the capability for image quantitation.FPC included attenuation,scatter,resolution recovery,and noise reduction.A standard NEMA phantom filled with 10:1 F-18 activity concentration ratio in spheres and background was utilized to evaluate image performance.Subsequently,15 patients with histologically confirmed thoracic carcinomas were included to undergo a 18 F-FDG Co-SPECT/CT scan followed by a 18 F-FDG PET/CT scan.Functional parameters as SUVmax,SUVmean,SULpeak,and MTV from both quantitative Co-SPECT and PET were analyzed.Image resolution of Co-SPECT for NEMA phantom was improved to reveal the smallest sphere from a diameter of 28 mm to 22 mm(17 mm for PET).The image contrast was enhanced from 1.7 to 6.32(6.69 for PET) with slightly degraded uniformity in background(3.1% vs.6.7%)(5.6% for PET).Patients’ SUVmax,SUVmean,SULpeak,and MTV measured from quantitative Co-SPECT were overall highly correlated with those from PET(r=0.82-0.88).Adjustment of the threshold of SUVmax and SUV to determine SUVmean and MTV did not further change the correlations with PET(r=0.81-0.88).Adding full physical corrections to Co-SPECT images can significantly improve image resolution and contrast to reveal smaller tumor lesions along with the capability to quantify functional parameters like PET/CT.
文摘To the best of our knowledge no multicenter studies have been published using standardized semi-quantitative evaluation of [123I]FP-CIT scan (DAT-SPECT). The aims of this study were: 1) to cross-compare semi-quantitative software-assisted evaluations of DAT-SPECTs performed in three centers with different equipments;2) to assess the accuracy of semi-quantitative evaluations of DAT-SPECT and 3) to identify the threshold with the best accuracy, sensitivity and specificity in a patient population with suspected parkinsonian syndrome. Materials and Methods: Two hundred twenty patients (mean age at the time of SPECT acquisition, 67.4 ± 9.5 yy) acquired in three centers (Ospedale San Luigi Gonzaga;Ospedale San Giovanni Battista Molinette;Ospedale Mauriziano Umberto I) were included. All of them underwent DAT-SPECT from January 2006 to July 2010. All exams were analyzed with the freely available software BASGAN and semi-quantitative data were used to predict disease. In particular, analyses were based on the values from the most deteriorated putamen and caudate, normalized for age and corrected for equipment. ROC analysis was performed and area under the curve (AUC) was estimated. Results: Analysis showed high AUCs (0.898, 0.864, 0.900 and 0.891 for each center and for the multicenter setting, respectively) confirming the very good accuracies reached. The best cut-off were 0.72 and 0.82 for putamen and caudate respectively. These thresholds allowed sensitivities and specificities in each center and in the multicenter setting of 76% and 96%, 91% and 82%, 93% and 90%, 86% and 89% respectively. No significant differences were observed between sensibility and specificity in each center. Conclusion: A unique threshold useful for all centers with high and similar sensitivities and specificities is possible after correction for age and equipments. The high accuracy reached in this multicenter trial by the semi-quantitative analysis seems similar to accuracies from qualitative analysis in other multicenter studies.
