J Korean Ophthalmol Soc.  1975 Mar;16(1):16-23.

Effect of Strontium 90 Beta-Irradiation, In Vitro on the Distensibility of the Cornea and Sclera of the Rabbit

• Choi SG

Abstract

Many methods have been proposed to measure the distensibility of the cornea and sclera, which is ecsential in tonography and tonometry of the eye ball, but little has been reported on the distensibility of the cornea and sclera expressed as Young Modulus, and the changes of the distensibility by beta-irradiation. In the present study, an attempt was made to elucidate the distensibility of the strip of the cornea or sclera, which was placed in the tension-length measuring apparatus immediately after removing from the apparently healthy normal rabbit without anesthesia. Young Modulus of the strip was calculated from the tension-length curve of each sample. Aho strontium 90 beta-irradiation was applied to the cornea and sclera in vitro, and the change of Young Modulus at 1,3,6,12 and 24 hours after beta-irradiation was compared with the normal and control. The results thus obtained are summarized as follows: 1. Young Modulus of the cornea and sclera in the normal rabbit was 2.25 X 10(7) dyne/cm2 and 6.60 X 10(7) dyne/cm2, respectively. 2. When 2,000 Rad of beta-ray was irradiated to the cornea and sclera in vitro, Young Modulus was similar to the control value at one hour, but beta-irraidiaton with 4,000 and 6,000 Rad produced decreased Young Modulus from the control at one hour after the irradiation. The tendency of the decrease was more noticeable in the cornea than in the sclera. 3. Young Modulus of the cornea at 6 hrs after beta-irradiation with 6,000 Rad in vitro did not change from the normal, but the decreased values were observed at 12 and 24 hrs after the irradiation while Young Modulus of the control group showed continuously elevated value from the normal up to 24 post-beta irradiation hour. 4. When 6,000 Rad of beta-ray was irradiated, Young Modulus of the sclera did not change greately from the normal value throughout the entire experiment. In the control group, however, the gradually elevated Young Modulus was observed up to 24 experimental hour.

MeSH Terms

Anesthesia
Cornea*
Elastic Modulus
Manometry
Reference Values
Sclera*
Strontium*
Strontium