Cobalt-60조사가 백서악골에 미치는 영향에 관한 실험적 연구

Abstract

[한글]

악골에 방사선을 조사하면 악골조직의 손상과 기능상의 이상이 초래된다는 것은 이미 잘 알려진 사실이나 저자는 Cobalt-60을 단일화 및 분활조사시 악골조직에 미치는 영향을 규명코자 60마리의 백서(체중 200gr 내외)를 각 15마리씩 4개군으로 나누어 제1군은 대

조군으로, 나머지 3군은 실험군으로 사용되었다.

실험군은 조사거리 100cm 매분당 72.6rad로 단회 및 분활 조사하였는데 제2군은 1,500rad (21.19분)를 단회조사 하였고, 제3군은 2,400rad를 800rad (11.29분)씩 24시간 간격으로 3회 분활 조사하였으며, 제4군은 2,650rad를 530rad (7.21분)씩 24시간 간격으로 5회 분활조사 하였다.

조사후 3일, 1, 2, 3, 4 주의 간격으로 실험동물을 회생시켜 악골조직을 절취하여 10% formalin에 고정 한후 5% 질산요액에 탈회한다음 악골조직편을 paraffin에 몰하여 표본을 7μ 두께로 박편을 만들어 H-E중 염색한후 조직표본을 검경하여 다음과 같은 유외할만한 결론을 얻었다.

1. 골수내에 울혈, 출혈 및 염증성세포 침윤(거대핵세포 및 임파구)과 지방변성이 나타났다.

2. 조골세포와 섬유아세포의 감소를 보였다.

3. 골 자체의 파괴는 볼 수 없었다.

4. Cobalt-60을 단일회 조사시 보다도 분활조사시가 골수내 변화가 심했으며 이중 800rad 조사군이 가장 심했고 시간이 경과함에 따라 그 정도가 더 뚜렷했다.

[영문]

It is a well known fact that x-ray irradiation brings about damage to the jaw bone tissue and cause functional abnormalities. To clarify the effects of irradiation on the jaw bone tissues, the changes of blood vessels in bone and bone cells were compared with a single dose and fractionated dose by the following exposure schedule.

Sixty white rats, about 200 gram body weight, were divided into four subgroups of fifteen animals, and the first subgroup served as an unirradiated control group. A total of 1,500 rad was given in a single dose to subgroup 2 with 100cm SFD (72.6rad/min. for 21.19 min.). Subgroup 3 and 4 received a fractionated dose within

the interval of 24 hours.

Subgroup 3 was subjected to a dose divided into three fractions for a total dose of 2,400 rad (800rad/fraction) and subgroup 4 was subjected to a dose divided into five fractions for a total dose of divided into five fraction for a total dose of 2,650 rad (530rad/fraction) with 100cm SFD.

The animals were sacrified at 3 days, 1, 2, 3, and 4 weeks after the last irradiation. The jaw bone tissues were fixed in 10% formalin, decalcified with 5% nitric acid, and embeded in paraffin. The specimens were sectioned to 7μm in thickness and were stained with homatoxlin-cosin for histological observation.

The results are as follows;

1. The changes in bone marrow showed congestion and hemorrhage of blood vessels, and megakaryotic cells and the chronic inflammatory cell, lymphocytes were present.

2. Osteblasts and fibroblasts were decreased in jaw bone tissues.

3. General features of jaw bone itself showed little change.

4. The above results demonstrate that fractionated doses are more damaging than a single dose and that three fractionated doses have a stronger effect than five. Moreover, jaw bone tissues were remarkably changed by time summation.