Huanhuan Liu1, Fuhua Yan2, Zilai Pan2, Xiaozhu Lin2, Xianfu Luo2, Cen Shi2, Xiaoyan Chen3, Baisong Wang4, Huan Zhang5. 1. Department of Radiology, Ruijin Hospital Affiliated to Shanghai Jiaotong University, School of Medicine, Shanghai 200025, China; Department of Radiology, Xinhua Hospital affiliated to Shanghai Jiaotong University School of Medicine. 2. Department of Radiology, Ruijin Hospital Affiliated to Shanghai Jiaotong University, School of Medicine, Shanghai 200025, China. 3. Department of Pathology, Ruijin Hospital Affiliated to Shanghai Jiaotong University, School of Medicine, Shanghai 200025, China. 4. Department of Biomedical Statistics, Shanghai Jiaotong University, School of Medicine, Shanghai 200025, China. 5. Department of Radiology, Ruijin Hospital Affiliated to Shanghai Jiaotong University, School of Medicine, Shanghai 200025, China. Electronic address: huanzhangy@126.com.
Abstract
OBJECTIVES: To investigate the value of dual energy spectral CT (DEsCT) imaging in differentiating metastatic from non-metastatic lymph nodes in rectal cancer. METHODS: Fifty-five patients with rectal cancer underwent the arterial phase (AP) and portal venous phase (PP) contrast-enhanced DEsCT imaging. The virtual monochromatic images and iodine-based material decomposition images derived from DEsCT imaging were interpreted for lymph nodes (LNs) measurement. The short axis diameter and the normalized iodine concentration (nIC) of metastatic and non-metastatic LNs were measured. The two-sample t test was used to compare the short axis diameters and nIC values of metastatic and non-metastatic LNs. ROC analysis was performed to assess the diagnostic performance. RESULTS: One hundred and fifty two LNs including 92 non-metastatic LNs and 60 metastatic LNs were matched using the radiological-pathological correlation. The mean short axis diameter of metastatic LNs was significantly larger than that of the non-metastatic LNs (7.28±2.28mm vs. 4.90±1.64mm, P<0.001). The mean nIC value for metastatic LNs was significantly lower than that of non-metastatic LNs (0.24±0.08 vs. 0.34±0.21, P=0.001 in AP; 0.47±0.18 vs. 0.64±0.17, P<0.001 in PP). Combining nIC (PP) with the short axis diameter, the overall accuracy could be improved to 82.9%. CONCLUSIONS: With the combination of nIC value in PP and conventional size criterion, dual energy spectral imaging may be used to differentiate metastatic from non-metastatic lymph nodes in rectal cancer.
OBJECTIVES: To investigate the value of dual energy spectral CT (DEsCT) imaging in differentiating metastatic from non-metastatic lymph nodes in rectal cancer. METHODS: Fifty-five patients with rectal cancer underwent the arterial phase (AP) and portal venous phase (PP) contrast-enhanced DEsCT imaging. The virtual monochromatic images and iodine-based material decomposition images derived from DEsCT imaging were interpreted for lymph nodes (LNs) measurement. The short axis diameter and the normalized iodine concentration (nIC) of metastatic and non-metastatic LNs were measured. The two-sample t test was used to compare the short axis diameters and nIC values of metastatic and non-metastatic LNs. ROC analysis was performed to assess the diagnostic performance. RESULTS: One hundred and fifty two LNs including 92 non-metastatic LNs and 60 metastatic LNs were matched using the radiological-pathological correlation. The mean short axis diameter of metastatic LNs was significantly larger than that of the non-metastatic LNs (7.28±2.28mm vs. 4.90±1.64mm, P<0.001). The mean nIC value for metastatic LNs was significantly lower than that of non-metastatic LNs (0.24±0.08 vs. 0.34±0.21, P=0.001 in AP; 0.47±0.18 vs. 0.64±0.17, P<0.001 in PP). Combining nIC (PP) with the short axis diameter, the overall accuracy could be improved to 82.9%. CONCLUSIONS: With the combination of nIC value in PP and conventional size criterion, dual energy spectral imaging may be used to differentiate metastatic from non-metastatic lymph nodes in rectal cancer.
Authors: Roberto García-Figueiras; Sandra Baleato-González; Anwar R Padhani; Ana Marhuenda; Antonio Luna; Lidia Alcalá; Ana Carballo-Castro; Ana Álvarez-Castro Journal: Insights Imaging Date: 2016-04-30