Lens opacities among physicians occupationally exposed to ionizing radiation – a pilot study in Finland

Abstract

Mrena S, Kivelä T, Kurttio P, Auvinen A. Lens opacities among physicians occupationally exposed to ionizing radiation-a pilot study in Finland. Scand J Work Environ Health. 2011;37(3):237-243. doi:10.5271/sjweh.3152.Objectives The aim of this study was to estimate the prevalence of lens opacities among physicians occupationally exposed to radiation overall and by occupational factors and to assess the feasibility of a large-scale study for risk assessment.Methods Based on a nationwide registry of 1312 physicians, mostly radiologists with occupational exposure to ionizing radiation, 120 subjects were invited to participate, of which 59 (49%) consented. The inclusion criteria included (i) age 45-70 years, (ii) cumulative recorded radiation dose >10 mSv, and (iii) duration of work with dose monitoring >15 years. The participants completed a questionnaire regarding occupational history and other risk factors for lens opacities. A full ophthalmological examination was performed. Lenticular changes were graded using the Lens Opacities Classification System, version II (LOCS II), and the Nidek EAS-1000 Scheimpflug slit-imaging videophotography system.Results Lens opacities were detected in 42% [95% confidence interval (95% CI) 29-55] of the 57 physicians without prior cataract surgery. Nuclear opacities were found in 14% (95% CI 6-26), cortical in 7% (95% CI 2-17), and posterior subcapsular in 5% (95% CI 1-15) of the subjects. The prevalence of lens opacities increased with age, smoking, and cumulative recorded radiation dose. After controlling for age, gender, and smoking, the excess odds ratio for any lens opacity was 0.13 (95% CI -0.02-0.28) per 10 mSv of cumulative radiation dose. ConclusionsOur preliminary results show cortical and posterior subcapsular lens opacities among physicians exposed to occupational radiation, consistent with recent studies on low-dose radiation exposure. A full study with an unexposed reference group for risk estimation is warranted.

Use of personal radiation protection tools and individual dosimetric monitoring in a sample of interventional cardiologists in France, 2005–2009

“…In Finland, however, a study of radiation-induced cataracts considered measurements from chest dosimeters worn outside the lead apron as indicators of the eye dose (Mrena et al, 2011). The validity of this study depends on two assumptions: that individual dosimeters were always worn and that chest dosimeters are a good indicator of eye exposure.…”

Ionizing Radiation as a Risk Factor for Cataract: What about Low-Dose Effects?

“…In Worgul et al [12], uncertainties on the estimated doses remain an important limit of the paper, even if the impact of dose uncertainty on the results was assessed. In medical staff studies, doses were either based on passive dosimetry (chest badge) [28] which may not be a good index for eye lens exposure, especially when radiation protection eyewear is used, or based on description of workload in terms of procedures and mean doses per procedure, which may suffer from memory bias [29][30][31]. However, radiation-induced cataracts have been globally observed in different exposed populations at lower doses (< 1 Gy) than the expected dose threshold of 2 Gy.…”

“…Interventional radiologists and cardiologists: Mrena et al [28] studied the prevalence of lens opacities among 57 physicians from Helsinki, occupationally exposed to radiation (including some interventional radiologists). They all had an eye examination and LOCS 2 was used to grade nuclear, cortical and posterior subcapsular lens opacities.…”

Radiation Protection from the Point of View of Patients of the Radiology Department at the University Clinical Hospital in Białystok

“…W literaturze przedmiotu zwraca się uwagę, że w badaniach prowadzonych w Skandynawii i Francji stwierdzono korelację między występowaniem zaćmy a pracą związaną z narażeniem na promieniowanie jonizujące [28][29][30]. Badania amerykań-skie Doody et al dotyczące ryzyka wystąpienia raka piersi u kobiet zatrudnionych w placówkach, gdzie istnieje ryzyko narażenia na promieniowanie, wykazały, że rak piersi jest skorelowany z okresem zatrudnienia [31].…”

“…Polega ona na tym, że badania radiologiczne powinny być wykonywane u kobiet miesiączkujących jedynie w pierwszych 10 dniach cyklu menstruacyjnego. Pacjentki będące w cią-ży są zobligowane do powiadomienia lekarza lub pracownika wykonującego badanie o swoim stanie przed wykonaniem badania rentgenowskiego [28]. Także matki karmiące piersią powinny unikać zwiększonej ekspozycji na szkodliwe działanie promieniowania.…”