Previous experiments by one of us (P. J. L.) in 19531 have demonstrated that the irradiation of one quadrant of the lens with x-rays results in opacity limited to the area of exposure. In our original work low doses were used and incomplete cataract resulted. More recently, in an attempt to produce rapidly an overwhelming effect in one sector of the lens, considerably larger doses of radiation were utilized.
EXPERIMENTAL STUDY
Albino rabbits of approximately 2 kg. were used in the experiments. X-ray exposure factors were 200 kv., 5 ma., 27 cm. distance, 150 r per minute, and 1 mm. Al filtration. Single exposures measured in air with a Victoreen r-meter were employed. Exposure of the lens was limited by lead shield (Fig. 1), sutured to the sclera of the anesthetized rabbit. Further shielding was obtained by covering the remainder of the animal with sheet lead. One quadrant of