Dose Reduction Of A Full-field Organ Dose Modulation On Cervical-thoraco-abdominopelvic Contrast Enhanced CT Of Female Chemotherapy Patients

Objective: To investigate the use of Organ Dose Modulation on cervical thoracic abdominal pelvic contrast enhanced CT of female chemotherapy patients to assess the radiation dose and image quality.Methods: 80 female chemotherapy patients undergoing cervical-thoracic-abdominal-pelvic enhanced CT were randomly divided into two groups: group A(Full-field ODM group)and group B(conventional group),each with 40 patients.We compared the tube current of the anterior,left,posterior and right aspects of the thyroid,breast and ovary layers.The average tube current of arterial and venous phases were also compared.We recorded the CTDIvol and the DLP,calculated the ED,measured the SNR and CNR of the thyroid,breast and ovary layers at arterial and venous phases.Two radiologists scored the image quality of all the images according to the five-point scale.Statistical analyze was made.Results: There were no statistically significant difference in SNR and CNR between group A and group B at arterial and venous phases of the thyroid,breast and ovary layers.The subjective scores of image quality between the two groups were of no significant difference,both of which were ≥ 3 points,all of the images were satisfying the clinical requirement(P>0.05).In group A,the tube current on anterior,left,posterior and right aspects of the thyroid,breast and ovary layers at both arterial and venous phases [324.46±53.2,327.97±61.34(thyroid),243.13±50.04,248.32±60.33(breast),332.28±71.50,339.78±76.69(ovary)] were lower than group B[407.60±96.81,402.73±90.15(thyroid),313.00±106.68,315.20±106.73(breast),457.78±106.56,459.63±106.27(ovary)].The difference was statistically significant.The use of ODM reduced the mean CTDIvol for 22%,the mean DLP for 24%.The mean ED of the neck,chest and abdominal-pelvic was decreased by 19.3%,21.4% and 26.4%,respectively(P<0.05).Conclusion:The use of ODM can reduce the radiation dose of female chemotherapy patients undergoing cervical-thoracic-abdominal-pelvic contrast enhanced CT,especially radiation sensitive organs,while maintaining the image quality.