Application of full-field organ dose modulation on cervical- thoraco-abdominopelvic contrast-enhanced computed tomography.

BACKGROUND AND OBJECTIVE To study the radiation dose and image quality on the use of full-field organ dose modulation (ODM) on cervical-thoracic-abdominal-pelvic contrast-enhanced computed tomography (CT) scanning on female chemotherapy patients. METHODS Eighty female chemotherapy patients undergoing cervical-thoracic-abdominal-pelvic contrast-enhanced CT were prospectively enrolled and randomly divided into two groups: group A and group B, each with 40 patients. Full-field ODM technique was used on group A and regular scanning patterns were used on group B. We calculated and recorded the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), subjective scores, mean tube currents of the anterior, left, posterior, and right aspects of the thyroid, breast, and ovary layers of all the images. The CT dose index volume (CTDIvol) and dose-length product (DLP) of each patient were recorded and the effective radiation dose (ED) was calculated. The above data were statistically analyzed. RESULTS There were no statistically significant differences in the SNR, CNR, and image quality scores of the thyroid, breast, and ovary layers of groups A and B during the arterial and venous phases (P > 0.05). The tube current on the anterior, left, posterior, and right aspects of the thyroid, breast, and ovary layers during the arterial and venous phases (thyroid: 324.46 ± 53.2 and 327.97 ± 61.34; breast: 243.13 ± 50.04 and 248.32 ± 60.33; ovary: 332.28 ± 71.50 and 339.78 ± 76.69; respectively) of group A were (statistically) significantly lower than those of group B (thyroid: 407.60 ± 96.81 and 402.73 ± 90.15; breast: 313.00 ± 106.68 and 315.20 ± 106.73; ovary: 457.78 ± 106.56 and 459.63 ± 106.27; respectively) (P < 0.05). The respective mean CTDIvol and DLP in group A were 22% and 24% lower than those of group B. The mean EDs of the neck, chest, and abdominal-pelvic region in group A were 19.3%, 21.4%, and 26.4% lower than those of group B, respectively (P < 0.05). CONCLUSION The use of ODM can reduce radiation dose of female chemotherapy patients undergoing cervical-thoracic-abdominal-pelvic contrast-enhanced CT, especially radiation-sensitive organs, while maintaining overall image quality.