Diagnostic value of the third generation Force dual energy CT in contusion and occult fracture of sacral pterygoid bone
XIA Haihong, GAO Yang, XIAO Yangrui, LIU Weiwen, YE Yongjun, CHEN Tao, ZHANG Wenwei, JI Jiansong.
Department of Radiology, Key Laboratory of Imaging Diagnosis and Minimally Invasive Intervention Research, the Fifth Affiliated Hospital of Wenzhou Medical University, Lishui 323000, China
XIA Haihong,GAO Yang,XIAO Yangrui, et al. Diagnostic value of the third generation Force dual energy CT in contusion and occult fracture of sacral pterygoid bone[J]. JOURNAL OF WEZHOU MEDICAL UNIVERSITY, 2021, 51(1): 30-34.
Abstract：Objective: To explore the value of the third generation Force dual energy CT virtual non-calcium (DECT-VNCa) map in the diagnosis of contusion and occult fracture of sacral alar under the condition of different relative contrast material ratio (RCMR). Methods: Totally 35 patients with definite history of pelvic trauma or lumbosacral pain in the past 3 years were prospectively collected for dual source CT dual energy scan and MRI examination. The RCMR values were 1.59, 1.79, 1.89, respectively. Three groups of DE-VNCa images were reconstructed. Taking MRI diagnosis as the gold standard, the efficacy of three groups of images was
calculated in the diagnosis of sacral pterygoid bone contusion and occult fracture, and the optimal RCMR value was obtained. Under this optimal condition, the CT values of sacral alar bone marrow edema area and contralateral normal area were measured and compared, and then the diagnostic efficacy of CT value in sacral alar occult fracture was evaluated by ROC curve. Results: When the RCMR values was 1.59, 1.79 and 1.89, the diagnostic efficacy of DE-VNCa was the highest, when Yoden index for the diagnosis of sacral alar bone marrow edema was 0.40, 0.81 and 0.71 respectively. Using RCMR=1.79 to reconstruct DE-VNCa map, the average CT value of bone marrow edema area was (-20.21±18.81) Hu, and the average CT value of contralateral normal bone marrow area was (-74.19±27.94) Hu. There was significant difference between sacral alar bone marrow edema area and contralateral normal area (P<0.001). Taking CT=-43.45 Hu as the critical value, the AUC for diagnosis of sacral alar bone marrow edema was 0.947 (P<0.001). Conclusion: Dual source CT DE-VNCa is of high clinical value in the diagnosis of sacral pterygoid bone contusion and occult fracture when RCMR is 1.79, and CT value is helpful in the diagnosis of sacral pterygoid bone contusion and bone marrow edema of occult fracture.
