Grave’s ophthalmopathy is thought to be an autoimmune disease associated with Grave’s goiter.The pathogenesis of Grave’s ophthalmopathy is less clear, but it is generally believed that the eye may share a common antigenic determinant cluster with the thyroid gland, and that when self-reactive thymus-dependent cells ( When T cells are activated by these antigen recognition, T cells and macrophages infiltrate and secrete a variety of cytokines. These cytokines act on fibroblasts in the retrobulbar tissue and extraocular muscle myofilaments, causing them to add value and secrete large amounts of glycosaminoglycans, leading to an increase in retrobulbar adipocytes and swelling of the retrobulbar tissue and extraocular muscle. The mechanism of radiation therapy for Grave’s ophthalmopathy is still unclear, and the effector target cells of radiation therapy still need to be determined. The possible mechanism is that the radiation kills the lymphocytes infiltrating the retrobulbar and extraocular muscles and acts on the fibroblasts and the process of glycosaminoglycan production. In the 1980s, it was recognized that orbital radiotherapy could produce considerable therapeutic effects, and the soft tissue behind the globe became the target area. After the 1980s, half-field irradiation was used, with the central axis of the beam located at the posterior edge of the lateral orbit, 9mm-15mm from the cornea, and the front half-field blocking the lead to maximize the protection of the crystal, reducing the crystal dose to 4% of the prescribed dose. Donaldson [2] showed that routine segmentation, 2Gy five times a week for a total of 20Gy, is an appropriate dose. The efficacy of radiation therapy for Grave’s ophthalmopathy has been confirmed in randomized controlled studies.The Mourits [3] randomized controlled study showed that 60% of patients treated with radiation were effective and 31% of blank control patients showed spontaneous improvement.The Prummel [4] randomized study showed that 52% of the radiation treatment group was effective and 27% of control patients showed spontaneous improvement. The same retrospective study also showed that radiation therapy was effective in 52% of the patients and 27% of the control patients. Bartalena [5] summarized the published literature on the treatment of Grave’s ophthalmopathy, showing that radiation therapy was effective in 59% of the 624 patients treated.Marquez [6] showed that 98% of patients Beckendore [7] analyzed the results of radiation therapy and showed 95% control and 5% disease progression. 99%. A stratified summary of the efficacy of radiation therapy for soft tissue changes, proptosis, visual acuity changes, eye movements, and corneal involvement is presented in the literature as follows. Soft tissue involvement Tsujino [8] treated 115 patients with combined soft tissue symptoms with radiation, 49% complete remission, 36% partial remission, and 15% no change. beckendore [7] treated 161 of the same patients with radiation, 86% effective, 11% stable, and 3% progressive. marquez [6] treated 177 patients showing 89% effective, 11% Stable. The results of Beckendore’s [7] analysis of changes in proptosis with radiation therapy showed that 91% of patients had control and 9% had worsening proptosis. 98 proptometer measurements showed that 36 patients were stable, 56 patients had a median improvement of 2 mm, only 4 patients had an improvement of more than 4 mm, and 6 patients had a median progression of 2 mm. Tsujino [8] reported the results of 115 patients with proptosis, 13% had complete remission, 31% had partial remission, 51% had no change, and 5% had worsening of symptoms. Visual acuity Tsujino [8] treated 57 patients with altered visual acuity with radiation therapy, 51% completely normalized, 12% improved, 32% unchanged, and 3% regressed. beckendore [7] reported the results of treatment in 24 patients with 83% control and 17% regression. marquez [6] showed results of radiation therapy in 49 patients, 67% improved, 25% unchanged, and 8 % regression. Oculomotor Tsujino [8] treated 114 patients with limited oculomotor activity with 21% complete remission, 60% partial remission, and 19% stable. 121 patients treated by Beckendore [7] showed 67% effective, 29% stable, and 4% progressive. 16 patients treated with radiation by Marquez [6] showed 85% effective, 13% stable, and 2% progressive. and 2% progression. Corneal involvement Marquez [6] radiotherapy of patients with corneal involvement showed complete remission in 21 (96%) patients and stable in 1 (4%) patient.Tsujino [8] results of 66 patients treated showed 47% complete remission, 6% partial remission, 42% stable and 5% progression.Beckendore [7] results of 25 patients treated with radiation showed 76% were effective, 12% were stable, and 12% progressed. III. Prognostic factors Disease course Grave’s ophthalmopathy goes through three typical periods, namely progressive, stable, and partial improvement, which last from about 6 months to 2 years. Radiation therapy is effective in reducing the patient’s early inflammatory symptoms, while other symptoms are less likely to achieve complete remission and the degree of remission is more variable. Once the inflammatory infiltrate is replaced by fibrotic changes, radiation therapy is hardly effective. Studies have shown that the earlier radiation therapy is started in the active phase of the disease, the more effective it is [7-8]. Dose Pfluger [9] compared the efficacy of irradiation doses of 10 Gy versus 16 Gy, and the authors concluded that a dose of 10 Gy was not sufficient.Kahaly [10] compared the efficacy of different irradiation doses in a randomized study and showed that the 10 Gy and 20 Gy groups were 55% and 67% effective, respectively.Petersen [11] compared the dose effect of conventional splitting of 30 Gy versus 20 Gy The results showed that the higher dose did not improve the therapeutic effect. Combined hormone therapy Most authors have observed that hormone therapy provides better relief of soft tissue swelling in Grave’s ophthalmopathy and that radiation therapy is effective in improving eye muscle movement. Hormones provide rapid relief of soft tissue changes, however, symptoms tend to recur when the dose of hormones is reduced, and the same prolongation of hormone therapy brings many associated side effects. In contrast, radiotherapy has a relatively delayed response but a long-lasting effect with no significant associated complications. Friedrich [12] compared the therapeutic effect of 26 Gy of radiotherapy with 13 Gy of radiotherapy combined with hormone and found that low-dose radiotherapy combined with hormone therapy could achieve the same therapeutic effect as high-dose radiotherapy, with an efficiency of 78% and 79.5%, respectively, and 5% and 5.5% for progressives. Tsujino [8] retrospectively analyzed the treatment results of 121 patients, and the efficacy was graded according to very good, good, fair, unresponsive, and exacerbated. 14 patients were treated with radiotherapy alone, and the efficacy was 0%, 36%, 43%, 14%, and 7%, respectively; 21 patients were treated with radiotherapy combined with oral low-dose hormone therapy, and the efficacy was 9.5%, 48%, 33%, 9.5%, and 0%, respectively; 50 patients The efficacy of radiotherapy combined with high-dose oral hormone therapy was 16%, 66%, 18%, 0% and 0%, respectively; the efficacy of radiotherapy combined with hormone shock therapy in 36 patients was 20%, 47%, 25%, 8% and 0%, respectively. Those who combined with oral high-dose hormone or shock therapy obtained better response than those who combined with radiotherapy alone and low-dose hormone (P = 0.0042). Radiation cataracts Radiation cataracts tend to develop in the posterior part of the lens and then to the periphery. The cloudy manifestation of the lens is often multi-lobed and clearly defined from the periphery. The single tolerated dose of the lens is 5 Gy, with a split dose of 10 Gy-15 Gy at different ages, and the latency period is from 6 months to several years, with an average of 2-3 years. With the correct radiotherapy technique, the dose to the lens can be ensured in the tolerated range. The appearance of radiation cataracts is often caused by irrational radiation techniques and excessive exposure doses [13]. Radiation retinopathy Radiation retinopathy mostly develops within 3 years after radiotherapy, with a peak incidence of 1 to 1.5 years. Clinical manifestations include a painless and dramatic decrease in visual acuity to blindness, a pale optic papilla with hemorrhage and exudation on fundus examination, visual field defects that are mostly quadrantal or D-side partial blindness and central dark spot, capillary nonperfused areas on the optic disc and in the retina on fundus fluorescence angiography, visual evoked potentials The amplitude was reduced and the latency was prolonged. The combination of diabetic and hypertensive retinal changes and concomitant chemotherapy often increases the incidence of radiation retinopathy [13]. Radiation-induced tumors The risk of radiation therapy-induced malignancy is of concern due to the benign nature of Grave’s ophthalmopathy. Theoretical calculations have shown that radiation therapy increases the risk of malignant tumor development. However, to date, no radiation-associated malignancies have been reported clinically in the orbital irradiated area [14]. To avoid radiation-induced tumors, it is recommended that radiation therapy be used with caution in patients with Grave’s ophthalmopathy aged <35 years, while minimizing the volume of irradiation. Radiation therapy for Grave's ophthalmopathy is safe and effective. Radiation therapy is the first-line treatment of choice for patients with active disease, and combined hormonal therapy may be considered for patients with severe disease. The correct application of radiation therapy techniques can avoid the occurrence of radiographic cataracts. Radiotherapy is relatively contraindicated in patients with combined diabetic and hypertensive retinal changes, and the possibility of radiation-induced malignancy still requires long-term clinical observation.