tailieunhanh - Evidence-Based Imaging - part 7

liều lượng bức xạ tích lũy vú là 10,8 CGY (từ 0-170). Tử vong do ung thư vú bảy mươi bảy đã được quan sát so với 45,6 ca tử vong dự kiến sẽ trên cơ sở tỷ lệ tử vong Hoa Kỳ. Phụ nữ với chứng vẹo cột sống có nguy cơ chết vì ung thư vú | 344 . Medina et al. cumulative radiation dose to the breast was cGy range 0-170 . Seventy-seven breast cancer deaths were observed compared with expected deaths on the basis of United States mortality rates. Women with scoliosis had a risk of dying of breast cancer 95 CI when compared with the general population. The data suggested that radiation was the causative factor with risk increasing significantly with the number of radiographic exposures and the cumulative radiation dose moderate evidence . Potential confounding was noted because the severity of disease was related to radiation exposure and reproductive history patients with more severe disease were less likely to become pregnant and had a greater risk of breast cancer. In a large retrospective cohort study of 2039 patients Levy and colleagues 75 found an excess lifetime cancer risk of 1 to 2 12 to 25 cases per 1000 population among women moderate evidence . The same group suggested that supplanting the anteroposterior AP view with the pos-teroanterior PA view would result in a three- to sevenfold reduction in cumulative doses to the thyroid gland and the female breast three- to fourfold reductions in the lifetime risk of breast cancer and a halving of the lifetime risk of thyroid cancer 76 . The same cohort of women was evaluated for adverse reproductive outcomes 77 . Of the initial group of 1793 young women evaluated for scoliosis between 1960 and 1979 1292 women returned questionnaires in 1990. This cohort was compared with a reference group of 1134 women selected randomly from the general population. The adolescent idiopathic scoliosis cohort had a higher risk of spontaneous abortions odds ratio OR 95 CI moderate evidence . The odds of unsuccessful attempts at pregnancy OR 95 CI and of congenital malformations OR 95 CI were also higher but not statistically significant moderate evidence . Digital radiography seems to reduce .