[Absorbed dose by the crystalline in middle ear tomography (author's transl)]

Measurements of the incident dose on the eye have been taken during the tomographic examinations of the middle ear. These measurements have been effectuated without any protection of the eye, and with a Pb-diaphragm protection, thickness 2mm. The tomograph which has been used is an Italian one (Eurostrator-Zuder, Genoa) provided with complex radiation movements (circular, spiral) and which gives technical resutlts such as the Polytom (generally used for these researches) but which has a focus film distance of 1m instead of 1.40 m. The average incident dose on the erystalline lens is high (11.7 R): the use of the Pb-diaphragm reduces the dose considerably (0.65 R) without any significant imperfections on the radiological image.