Patient Dose Reduction for Chest Examination in Hospitals along Andaman Coast - การลดปริมาณรังสีให้กับผู้ป่วยที่มาใช้บริการถ่ายภาพรังสีทรวงอกของโรงพยาบาลชายฝั่งทะเลอันดามัน

Abstract

          High radiation dose can induce radiation hazard for patient, the dose justification and optimization shall be considered in hospital. In 2010, Regional Medical Science Center 1 and Bureau of Radiation and Medical Devices provided a training course for radiation worker on the technique for patient dose reduction while undergoing radiograph. The training course had been operated for radiation workers from Central and Southern Thailand in March 2010. The entrance surface doses before and after training program, for chest posteroanterior examination of patients with thickness between 22 ± 5 centimeters in 14 hospitals in Trang, Krabi, Phangnga and Phuket were compared. It was found that the doses were significantly different at level of significance 0.05. The doses were reduced in 12 hospitals (85.7%); the third quartile value was down from 0.56 to 0.38 milliGreymGy, or reduced by 0.18 mGy (32.1%). The doses reportedly varied less among those in the group showing negative trend of max/min ratio from 20.19 down to 19.38. When the exposure factor had been considered as measured in terms of differnce in kilovolt, an increase by 3.3 kilovolt (4.3%) was reported, yet the milliampere-sec (mAs) decreased to 7.2 mAs (39.2%). It could be concluded that the patient dose has been reduced after the training program, so it should be replicated in other hospitals in Thailand.
Key words: entrance surface dose, chest examination, exposure factor