The analysis of doses and image at chest radiography using an Active Breathing Coordinator (ABC) system

Abstract

In this study, we attempted a comparative analysis of the dose and imaging difference between the deep inhalation (DI) and deep exhalation (DE) chest radiography of the same region. Healthy volunteers (n $$=$$= 30; 27 men and 3 women) free of chest disease in their 20s, 30s, and 40s were selected as the subjects of this study. We employed an X-ray generator (Philips) with a built-in ion chamber and an Active Breathing Coordinator (ABC) system Version 1.02 (Elekta) with embedded software (Aktina Medical Co., USA) that produces graphs following breathing cycles. Significant differences (p $$<$$< 0.05) in statistical processing were analyzed with a $$t$$t test using SPSS version 18.0. The measurements of vital capacities using ABC during chest radiography resulted in overall mean air volumes of 2,220 and 1,507 ml during DI and DE, respectively, which yielded a vital capacity of 3,727 ml. The radiation doses of 30 volunteers during chest radiography were 8.50 $$\pm $$± 1.85 $$\upmu $$μGym$$^{2}$$2 and 11.29 $$\pm $$± 4.71 $$\upmu $$μGym$$^{2}$$2 during DI and DE, respectively, thereby demonstrating a 32 % increase during DE compared to DI. The 95 % confidence interval of the difference between X-ray doses during DI and DE was 1.89---3.89 and showed a statistically significant difference (p $$=$$= 0.009). It was thereby verified that images with the same degree of sensitivity could be obtained with a lower dose during DI. The Cardiothoracic ratio in the DI and DE were 43.05 $$\pm $$± 3.70 and 54.53 $$\pm $$± 5.48 %. The 95 % confidence interval of the difference between Cardiothoracic ratio during DI and DE was 10.14---12.66 and showed a statistically significant difference (p $$=$$= 0.001). Histogram of gray values of chest image in the DI and DE were 144.67 $$\pm $$± 75.50 and 125.27 $$\pm $$± 75.46. Accurate chest radiography image can be obtained during DI examination than DE. Chest radiography during DI can reduce the patient's exposure from radiation dose.