Cataract formation after incorporation of radioactive iodine

• Published in: Acta ophthalmologica (Oxford, England) Vol. 88; no. s246
• Main Authors: DALKE, C, ROSEMANN, M, PUK, O, GRAW, J
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.09.2010
• ISSN: 1755-375X; 1755-3768
• DOI: 10.1111/j.1755-3768.2010.3144.x

Purpose The ocular lens is one of the most radiosensitive organs in mammals and a pathological sign after exposure to ionising radiation is the formation of cataracts. We generated a mouse model to mimic the situation after the accident in the Chernobyl power plant. Methods Pregnant and nursing FBV‐mice were treated with iodine131 for diaplacentar and galactogen transfer to the litter. The offspring which incorporated the radioiodine were examined for lens opacities at the age of 6 and 12 months. Iodine131 is a beta radiation emitting nuclide with a short half live of 8 days. Mothers were injected twice with 100 kBq I‐131, on day 14 post conception and day 6 post natal. Cataracts were investigated at 6 and 12 months of age using a slit lamp. Results Depending on the litter size and weight, a single progeny incorporates between 8 to 14 % of entire activity. More than 50% of the injected activity is transmitted from the mother to the entire offspring. Iodine is accumulated in the thyroid and an average thyroid dose of 3.7 Gy was calculated. Because of the short distance between the thyroid and the eye, a lens dose of 0.5 Gy was estimated. In the FBV mice, we observed at the age of 6 months two cataracts among 15 irradiated lenses (13%), but none among 7 unirradiated controls. At the age of 12 months, almost all lenses showed cortical cataracts in both groups. However, there were 17 nuclear cataracts among 66 irradiated lenses (25%), but only 1 among 16 controls (6%). Conclusion These preliminary data indicate that this method is sensitive enough to detect the cataract‐causing potential of low‐dose ionizing radiation in the mouse. However, for detailed analysis larger cohorts and quantification of the data are necessary.