Wilson-Costello D, Rao P S, Morrison S, Hack M
Department of Pediatrics and Radiology, Case Western Reserve University, Cleveland, Ohio, USA.
Pediatrics. 1996 Mar;97(3):369-74.
We sought to examine radiation doses received by infants of less than 750 g birth weight from radiographs.
We examined the radiology records, including radiograph films, of all 25 surviving infants with birth weight less than 750 g admitted to our center during 1991. The standard method of neonatal radiation dose calculation was modified to consider the body size, postnatal growth, and extramedullary hematopoiesis of the extremely low birth weight infant. To determine overall radiation exposure, we calculated an effective dose equivalent, which is the sum of weighed organ dose equivalents.
The infants had a mean of 31 radiographys performed, including 17 chest radiographs, 5 babygrams, and 9 abdominal radiographs. The majority of chest radiographs and babygrams were performed in the first month, whereas abdominal radiographs increased during the second month of life. Total-body radiation dose and total effective dose equivalent by the standard and modified methods, respectively, for single exposures ranged from 0.01 to 0.02 millisieverts (mSv) for a chest radiograph, from 0.02 to 0.04 mSv for a babygram, and from 0.02 to 0.03 mSv for an abdominal radiograph. Surface organs icluding the skin, breast, and thyroid received the largest radiation doses. The effective dose equivalent per infant for all radiographs was 0.72 mSv according to the modified method, compared to a total-body dose of 0.40 mSv using the standard method. However, infants with chronic lung disease or necrotizing enterocolitis received up to 1.5 mSv total-body dose, including 3.3 mSv to the breast, 2.5 mSv to the thyroid, and 2.3 mSv to the testes.
Radiation doses received by infants of less than 750 g birth weight are small in comparison with the range of doses that form the basis of risk estimates for cancer.
我们试图检测出生体重小于750克的婴儿因X光检查所接受的辐射剂量。
我们检查了1991年期间入住我们中心的所有25名存活的出生体重小于750克婴儿的放射学记录，包括X光片。对新生儿辐射剂量计算的标准方法进行了修改，以考虑极低出生体重婴儿的身体大小、出生后生长情况和髓外造血。为确定总体辐射暴露情况，我们计算了有效剂量当量，即加权器官剂量当量之和。
这些婴儿平均接受了31次X光检查，包括17次胸部X光检查、5次婴儿全身X光检查和9次腹部X光检查。大多数胸部X光检查和婴儿全身X光检查在出生后的第一个月进行，而腹部X光检查在出生后的第二个月有所增加。单次照射时，按照标准方法和修改后的方法计算的全身辐射剂量和总有效剂量当量，胸部X光检查的范围分别为0.01至0.02毫希沃特（mSv），婴儿全身X光检查为0.02至0.04 mSv，腹部X光检查为0.02至0.03 mSv。包括皮肤、乳房和甲状腺在内的体表器官接受的辐射剂量最大。根据修改后的方法，所有X光检查中每名婴儿的有效剂量当量为0.72 mSv，而使用标准方法时的全身剂量为0.40 mSv。然而，患有慢性肺病或坏死性小肠结肠炎的婴儿接受的全身剂量高达1.5 mSv，其中乳房接受3.3 mSv，甲状腺接受2.5 mSv，睾丸接受2.3 mSv。
与构成癌症风险估计基础的剂量范围相比，出生体重小于750克的婴儿所接受的辐射剂量较小。
