An analysis of the dose and the therapeutic effect of 131I in treating youngsters with Graves disease

Objective To analyses the clinical data of 131I in treating youngsters with Graves disease,and to explore the effective dose range which is appropriate for Chinese youngsters with Graves disease.Methods Two hundred and thirty-four youngsters with Graves disease were selected in this study, their ages were between 8 and 17, the average quality of their thyroids was(59.0±16.5)g. According to the absorbed dose of 131I per gram of thyroid gland, 234 patients were divided into five groups: A: 1.11-＜1.48 MBq/g, B: 1.48-＜1.85 MBq/g,C: 1.85-＜2.22 MBq/g,D: 2.22-2.59 MBq/g, E: ＞2.59 MBq/g. The therapeutic effect was evaluated by observing after treatment. And calculate the recovery rate, the improvement rate and the incidence rate of hypothyroidism. Results (①One hundred and fifty-two (64.95%) patients were cured, 56 (23.93%) were much better than before and 26 (11.11%) were hypothyroid. The therapeutic effect of group B was the best in all groups. ②The recovery rate: there was no significant difference between group B, group C and group D(χ2 =2.68, P＞0.05 ). The recovery rate of group B was better than group A and group E (χ2 = 10.20 and χ2 =5.49,P＜0.05 ). The recovery rate of group A was the lowest. ③The improvement rate: There was no significant difference between group B, group C, group D and group E(χ2 =1.94, P＞0.05 ). The improvement rate of group A was the highest(χ2 =8.74,χ2 =6.68,χ2 =7.01 and χ2 =11.12, P＜0.05 ). ④The incidence rate of hypothyroidism: There was no significant difference between group A, group B, group C and group D (χ2 =2.71, P＞0.05 ). Group E had the highest incidence rate of hypothyroidism(χ2 =12.36, χ2 =11.58,χ2=9.37 and χ2=4.36, P＜0.05 ). Conclusions Using 131I is a safe and effective therapeutic approach for youngsters with Graves disease. We suggest the absorbed dose range of 131I per gram of thyroid gland is 1.48-2.59 MBq/g,which can obtain the better therapeutic effect and can't increase the incidence rate of hypothyroidism. Key words: Graves disease ;  Brachytherapy ;  Iodine radioisotopes ;  Adolescent ;