[Dose distribution during irradiation of the retrobulbar space--results of measurements on a phantom].
The transverse dose distribution in case of X-ray and cobalt irradiation of the retrobulbar space was measured in a water phantom. As expected, the crystalline lens receives a smaller dose by cobalt irradiation with lead shielding in front of the eye than by X-irradiation. In case of cobalt irradiation, the dorsal portions lying within the hypophyseal region can only be sufficiently protected by a special block cast by us in a divergent form and surrounding the irradiation field. If X-ray irradiation is performed with a field size of 2 X 4 cm2, the 50% isodose encloses just the complete retrobulbar space. Taking into consideration a second contralateral field, the crystalline lens is exposed to less than 10% of the maximum dose. Thus the doses applied usually in radiotherapy of endocrine ophthalmopathy, i.e. 15 to 20 Gy, lead to an unproblematic crystalline lens exposure of 150 to 200 rad.
D003037:Cobalt Radioisotopes / Q000008:administration & dosage; D005128:Eye Diseases / Q000532:radiotherapy*; D006801:Humans; D007908:Lens, Crystalline / Q000528:radiation effects; D008953:Models, Anatomic; D011835:Radiation Protection; D011879:Radiotherapy Dosage
D003037:Cobalt Radioisotopes
Die Dosisverteilung bei Bestrahlung des Retrobulbärraumes--Messergebnisse am Phantom.