Cumulative Radiation Dose from Radiography in Preterm Infants during Hospitalisation

Full Article

KYK Lau, SCN Hui, HM Cheung, PC Ng, WCW Chu

Hong Kong J Radiol 2016;19:183-91

DOI: 10.12809/hkjr1615349

Objectives: Preterm infants with low gestational age (GA) and very low birth weight experience high morbidity and mortality. Chest and abdominal radiographs are commonly performed in this group. The aim of this study was to estimate the trend of radiation exposure from radiographs in preterm infants.

Methods: In this retrospective study, 210 surviving infants were systematically reviewed. The entrance skin air kerma was measured followed by estimation of effective dose (ED) using the Monte Carlo simulation software (PCXMC 2.0). We estimated the risk of radiation-induced cancers based on referenced risk factors from the International Commission on Radiological Protection Publication 103.

Results: The median (interquartile range) GA, birth weight, and hospital stay of the infants was 29.2 (27.9-31.1) weeks, 1.2 (1.0-1.5) kg, and 68.5 (47.0-100.0) days, respectively. The median ED per chest and abdomen radiograph was 0.021 mSv and 0.026 mSv, respectively. Preterm infants with GA of <28 weeks received a median cumulative ED (cED) of 1.47 mSv, those of 28 to <30 weeks received a median cED of 0.84 mSv, and those of 30 to <32 weeks received a median cED of 0.39 mSv. Preterm babies with lower GA and longer hospital stay were at higher radiation risk from diagnostic radiography. Preterm infants with GA of <28 weeks and those who required surgery due to necrotising enterocolitis had the highest dose of cED.

Conclusion: Preterm infants were not exposed to excessive radiation during hospitalisation; dose risk for development of cancer was negligible. Nonetheless, the principle of ALARA (as low as reasonably achievable) should be applied.








方法:本研究為210名存活嬰兒進行系統性回顧。利用Monte Carlo模擬軟件(PCXMC 2.0)估計有效劑量然後量度入射皮膚劑量。根據國際放射防護委員會第103號出版物中的參考風險因素估計因輻射誘發癌症的風險。

結果:本研究中嬰兒的胎齡、出生體重和住院時間的中位數(四分位距)分別為29.2(27.9-31.1)週、1.2(1.0-1.5)千克和68.5(47.0-100.0)天。胸部和腹部X光檢查的有效劑量中位數分別為0.021 mSv和0.026 mSv。胎齡少於28週的早產嬰兒所接觸到的累計有效劑量中位數為1.47 mSv,28至少於30週的嬰兒為0.84 mSv,30至少於32週的嬰兒則為0.39 mSv。低胎齡和住院時間較長的早產嬰兒從放射診斷中接觸到較高輻射風險。胎齡少於28週以及因壞死性小腸結腸炎而需接受手術的早產嬰兒有最高的累計有效劑量。