A retrospective study on the efficacy of total absorbed orbital doses of 12, 16 and 20 Gy combined with systemic steroid treatment in patients with Graves' orbitopathy

Management of Graves' ophthalmopathy by radiotherapy: A literature review

Orbital radiotherapy for Graves' ophthalmopathy is an example of non-oncological radiotherapy. First introduced in the 1930s, this treatment has become widely used since the 1980s with several studies showing proof of both effectiveness and safety: a decrease of soft tissue involvement in 70 to 80% of patients and an improvement of ocular mobility in 30 to 80% of patients. Nowadays, it's one of the second line treatment options recognized by the European Group on Graves' orbitopathy in the management of a moderate to severe and active disease after failure of glucocorticoids. In that setting, orbital radiotherapy should be combined with glucocorticoids. To our knowledge, there are no practical recommendations on how orbital radiotherapy should be planned and conducted for Graves' ophthalmopathy. Optimal dose is not defined however the most frequent regimen consists of 20Gy in ten fractions of 2Gy, though other options may yield better results. Lastly, the use of modern technique of radiotherapy such as intensity-modulated radiation therapy may allow a better sparing of organs at risk compared to three-dimensional radiotherapy using lateral opposing fields.

[Interdisciplinary Management of Orbital Diseases]

Diagnosis and therapy of orbital diseases is an interdisciplinary challenge, in which i.e. otorhinolaryngologists, ophthalmologists, radiologists, radiation therapists, maxillo-facial surgeons, endocrinologists, and pediatricians are involved. This review article describes frequent diseases which both, otolaryngologists and ophthalmologists are concerned with in interdisciplinary settings. In particular the inflammatory diseases of the orbit including orbital complications, autoimmunological diseases of the orbit including Grave´s orbitopathy, and primary and secondary tumors of the orbit are discussed. Beside describing the clinical characteristics and diagnostic steps the article focusses on the interdisciplinary therapy. The review is completed by the presentation of most important surgical approaches to the orbit, their indications and possible complications. The authors tried to highlight the relevant facts despite the shortness of the text.

Current Therapeutic Approaches for Graves' Orbitopathy - are Targeted Therapies the Future?

Graves' orbitopathy is an autoimmune disease of the orbit that most frequently occurs with Graves' hyperthyroidism. The occurrence of autoantibodies directed against the TSH receptor (TRAb) is of central importance for the diagnosis and pathogenesis. These autoantibodies are mostly stimulating, and induce uncontrolled hyperthyroidism and tissue remodelling in the orbit and more or less pronounced inflammation. Consequently, patients suffer to a variable extent from periocular swelling, exophthalmos, and fibrosis of the eye muscles and thus restrictive motility impairment with double vision. In recent decades, therapeutic approaches have mainly comprised immunosuppressive treatments and antithyroid drug therapy for hyperthyroidism to inhibit thyroid hormone production. With the recognition that TRAb also activates an important growth factor receptor, IGF1R (insulin-like growth factor 1 receptor), biological agents have been developed. Teprotumumab (an inhibitory IGF1R antibody) has already been approved in the USA and the therapeutic effects are enormous, especially with regard to the reduction of exophthalmos. Side effects are to be considered, especially hyperglycaemia and hearing loss. It is not yet clear whether the autoimmune reaction (development of the TRAb/attraction of immunocompetent cells) is also influenced by anti-IGF1R inhibiting agents. Recurrences after therapy show that the inhibition of antibody development must be included in the therapeutic concept, especially in severe cases.

[Graves' orbitopathy: Current concepts for medical treatment]

BACKGROUND

The therapy of severe manifestations of Graves' orbitopathy (GO) is still a challenge and requires good interdisciplinary cooperation. It is especially important to use stage-adapted anti-inflammatory therapy to avoid irreversible damage.

MATERIAL AND METHODS

Discussion of the latest results of multicentre randomised therapy studies on anti-inflammatory treatments for Graves' orbitopathy, as well as new therapeutic concepts.

RESULTS

Mild cases of GO can be treated with only selenium supplementation and a watchful waiting strategy. In the moderate-to-severe active form of GO, primary therapy consists of i. v. steroids (cumulative 4-5 g) in combination with orbital irradiation in patients with impaired motility. In patients with insufficient therapeutic response after 6 weeks, treatment should be switched to other immunosuppressive agents. In severe sight-threatening disease, bony orbital decompression is usually necessary. As basic research has improved our understanding of the underlying pathophysiology of GO, it has been possible to develop targeted therapies for GO. Teprotumumab, an IGF-1 receptor antibody, was effective in treating GO patients in a phase III trial and should soon be awarded approval for Europe.

CONCLUSION

The current therapy concept for Graves' orbitopathy is as follows: first anti-inflammatory therapy then surgical correction of the permanent defects. This may soon be modified, due to the use of targeted therapies.

Orbital Radiation for Thyroid Eye Disease: A Report by the American Academy of Ophthalmology

PURPOSE

To review the current literature on the safety and efficacy of orbital radiation for the management of thyroid eye disease (TED).

METHODS

A literature search was conducted last in February 2021 of the PubMed database to identify all articles published in the English language on original research that assessed the effect of orbital radiation on TED. The search identified 55 articles, and 18 met the inclusion criteria for this assessment. A panel methodologist then assigned a level of evidence rating for each study, and all of them were rated level III.

RESULTS

Two large retrospective studies demonstrated the efficacy of radiation treatment, with or without corticosteroid use, in preventing or treating compressive optic neuropathy (CON). Three studies highlighted the role of orbital radiation therapy (RT) to facilitate the tapering of corticosteroids. Several other studies showed a possible role for RT to improve diplopia and soft tissue signs.

CONCLUSIONS

Although no level I or level II evidence exists, the best available evidence suggests that orbital radiation, used with or without corticosteroids, is efficacious in preventing CON, improving motility restriction, and decreasing clinical activity in TED. Orbital radiation also may facilitate a corticosteroid taper. Together, these studies show that RT seems to modify the active phase of TED. Short-term risks of orbital radiation are minor, but long-term outcome data are lacking.

Teprotumumab: The Dawn of Therapies in Moderate-to-Severe Thyroid-Associated Ophthalmopathy

Thyroid-associated ophthalmopathy (TAO) is a potentially sight-threatening ocular disease. About 3-5% of patients with TAO have severe disease with intense pain, inflammation, and sight-threatening corneal ulceration or compressive optic neuropathy. The current treatments of TAO are often suboptimal, mainly because the existing therapies do not target the pathogenesis of the disease. TAO mechanism is unclear. Ocular fibrocytes express relatively high levels of the functional TSH receptor (TSHR), and many indirect evidences support its participation. Over expression of insulin-like growth factor-1 receptor (IGF-IR) in fibroblasts, leading to inappropriate expression of inflammatory factors, production of hyaluronic acid and cell activation in orbital fibroblasts are also possible mechanisms. IGF-1R and TSHR form a physical and functional signaling complex. Inhibition of IGF-IR activity leads to the attenuation of signaling initiated at either receptor. Teprotumumab (TMB) is a human immunoglobulin G1 monoclonal antibody, binding to IGF-IR. Recently two TMB clinical trials had been implemented in TAO patients, indicating dramatic reductions in disease activity and severity, which approved its use for the treatment of TAO in the US. This review summarizes the treatments of TAO, focusing on the pathogenesis of IGF-1R in TAO and its application prospects.

Graves' orbitopathy: a multidisciplinary approach

Orbitopathy is the main extra thyroidal manifestation of Graves' disease. It is a very challenging condition, which requires a cooperation between many specialists (endocrinologists, ophthalmologists, radiologists, radiotherapeutic, orbital surgeons) for an optimal clinical management. An accurate diagnostic assessment is required, in order to plan an adequate treatment of Graves' orbitopathy. Medical therapy, radiotherapy or surgery may be necessary to control the disease. In this review, the authors analyze the various therapeutic strategies, as well the more recent therapies based on pharmacologic immunomodulation.

Comparison of 2-wall versus 3-wall orbital decompression against dysthyroid optic neuropathy in visual function: A retrospective study in a Chinese population

To compare visual function of 2-wall (medial and lateral) versus 3-wall (medial, lateral, and inferior) orbital decompression in patients with dysthyroid optic neuropathy (DON).A total of 52 eyes of 37 patients underwent orbital decompression for DON between 2013 and 2019 were retrospectively reviewed. Two- or 3-wall decompression was performed in 31 eyes of 23 patients and 21 eyes of 14 patients, respectively. We examined best-corrected visual acuity (BCVA), visual field mean deviation (MD) and pattern standard deviation (PSD), pattern-reversed visual evoked potential (PVEP) for P100 latency and amplitude at 60 and 15 arcmin stimulation checkerboard size, as well as proptosis using Hertel exophthalmometry.Whether 2-wall or 3-wall decompression, all parameters of visual function were improved after surgery (all P < .05). The improvement in BCVA, MD, and PSD was not statistically significant between groups (all P > .05). Proptosis reduction was higher after 3-wall decompression (P = .011). Mean increase in P100 amplitude after 3-wall decompression was statistically higher than that of after 2-wall decompression at 60 and 15 arcmin (P = .045 and .020, respectively), while the mean decrease in P100 latency was similar between the groups (P = .821 and .655, respectively). Six patients (66.67%) had persistent postoperative diplopia and 1 patient (20%) had new-onset diplopia in 3-wall decompression group, which were higher than in 2-wall decompression group (46.15% persistent postoperative diplopia and no new-onset diplopia).Both 2-wall and 3-wall decompression can effectively improve visual function of patients with DON. Three-wall decompression provides better improvement in P100 amplitude and proptosis, however new-onset diplopia is more common with this surgical technique.

Graves' Orbitopathy: Current Concepts for Medical Treatment

BACKGROUND

The therapy of severe manifestations of Graves' orbitopathy (GO) is still a challenge and requires good interdisciplinary cooperation. It is especially important to use stage-adapted anti-inflammatory therapy to avoid irreversible damage.

MATERIAL AND METHODS

Discussion of the latest results of multicentre randomised therapy studies on anti-inflammatory treatments for Graves' orbitopathy, as well as new therapeutic concepts.

RESULTS

Mild cases of GO can be treated with only selenium supplementation and a watchful waiting strategy. In the moderate-to-severe active form of GO, primary therapy consists of i. v. steroids (cumulative 4 - 5 g) in combination with orbital irradiation in patients with impaired motility. In patients with insufficient therapeutic response after 6 weeks, treatment should be switched to other immunosuppressive agents. In severe sight-threatening disease, bony orbital decompression is usually necessary. As basic research has improved our understanding of the underlying pathophysiology of GO, it has been possible to develop targeted therapies for GO. Teprotumumab, an IGF-1 receptor antibody, was effective in treating GO patients in a phase III trial and should soon be awarded approval for Europe.

CONCLUSION

The current therapy concept for Graves' orbitopathy is as follows: first anti-inflammatory therapy then surgical correction of the permanent defects. This may soon be modified, due to the use of targeted therapies.

Clinical outcomes of hypofractionated radiotherapy for thyroid-associated ophthalmopathy

Objective

To evaluate the safety and effectiveness of hypofractionated orbital radiotherapy applied in the treatment of thyroid-associated ophthalmopathy (TAO) patients.

Methods

Between 2014 and 2018, we retrospectively reviewed the cases of 28 patients with TAO. All patients underwent radiotherapy on both retroocular tissues and received an oral steroid. Patients were divided into two treatment groups: 14 patients received conventional fractionated radiotherapy (20 Gy in 10 fractions), and the second group of 14 patients received hypofractionated radiotherapy (20 Gy in five fractions). The clinical activity score (CAS), NOSPECS (No physical signs or symptoms, Only signs, Soft tissue involvement, Proptosis, Extraocular muscle signs, Corneal involvement, and Sight loss) classification, Hess screen test and binocular single vision (BSV) were evaluated to determine the response to treatment before and at 1 month after radiotherapy.

Results

There were no significant differences in any of the variables between the two treatment groups. In both groups, the CAS and NOSPECS score decreased significantly, and the range of extraocular muscle motility in Hess screen test and BSV improved significantly after radiotherapy (p < 0.05). There were no significant differences in CAS, NOSPECS score, Hess screen test or BSV between the two groups. No radiation-related, acute severe toxicity was observed.

Conclusion

Hypofractionated radiotherapy for TAO produced a comparable clinical outcome to that of conventional fractionated radiotherapy. Further case accumulation and long-term follow-up are required to determine if late toxicity occurs and to confirm efficacy.

Advances in knowledge

This is the first study to show that the efficacy and risk of adverse events are comparable between hypofractionated radiotherapy and conventional radiotherapy in the treatment of TAO.

Contour Variability in Thyroid Eye Disease with Compressive Optic Neuropathy Treated with Radiation Therapy

Purpose

Few studies have evaluated the methodology by which radiation therapy (RT) for thyroid eye disease and compressive optic neuropathy is performed. The objective of this study was to retrospectively review our experience from a radiation planning standpoint and to determine whether current treatment methods provide adequate dose to target and collateral structures.

Methods

A retrospective review of 52 patients (104 orbits) with bilateral thyroid eye disease and compressive optic neuropathy treated with RT (20 Gy in 10 fractions) at our institution. RT plans were analyzed for target volumes and doses. Visual fields, color plates, and visual acuity were assessed pretreatment and at last available follow-up post RT. A standardized, anatomic contour of the retro-orbital space was applied to these retrospective plans to determine dose to the entire space, rather than the self-selected target structure.

Results

Compared with the anatomic retro-orbital space, the original contour overlapped by only 68%. Maximum and mean dose was 2134 cGy and 1910 cGy to the anatomic retro-orbital space. Consequently, 39.8% of the orbits had a mean dose <19 Gy (<17 Gy 16.4%, <18 Gy 27.6% <19 Gy 37.8%, <20 Gy 59.2%, 20-21 Gy 35.8%, >21 Gy 5%). There was no significant association of improvement in color plates (P = .07), visual fields (P = .77), and visual acuity (P = .62), based on these dose differences. When beam placement was retrospectively adjusted to include a space of 0.5 cm between the lens and the anterior beam edge, there was a 39.4% and 20.3% decrease in max and mean dose to the lens.

Conclusions

Without a standardized protocol for contouring in thyroid eye disease, target delineation was found to be rather varied, even among the same practitioner. Differences in dose to the anatomic retro-orbital space did not affect outcomes in the follow-up period. Although precise contouring of the retro-orbital space may be of little clinical consequence overall, a >0.5 cm space from the lens may significantly reduce or delay cataractogenesis.

Influence of orbital morphology on proptosis reduction and ocular motility after decompression surgery in patients with Graves' orbitopathy

PURPOSE

Orbital decompression surgery is performed in patients with Graves' orbitopathy to treat dysthyroid optical neuropathy (DON) and reduce disfiguring proptosis. The intended proptosis reduction can deviate from the postoperative result and changes of motility with consecutive diplopia can occur. We performed a retrospective study to identify anatomical factors in computed tomography (CT), which influence the surgical effect and postoperative ocular motility and diplopia.

METHODS

Pre- and postoperative CT-scans of 125 eyes of 68 patients, who mainly underwent a balanced orbital decompression for disfiguring proptosis (≥18mm Hertel Index), have been analyzed. Proptosis, ductions, misalignment and diplopia were assessed before and after surgery. Medial and lateral orbital wall length, conus angle, depth of ethmoidal sinus, orbital surface, length of medial and orbital defect, depth of tissue prolapse and horizontal muscle diameters were analyzed in CT scans before and after surgery. With linear regression and multivariate analyses these parameters have been correlated with postoperative proptosis, abduction deficit, deviation and binocular single vision (BSV).

RESULTS

Proptosis could be reduced by 5.3±2mm. Patients with <5mm proptosis reduction had significantly less often new onset of diplopia compared to patients with >5mm reduction (13% vs. 56%, p = 0.02). Multiple linear regression showed a significant correlation between tissue prolapse and depth of the ethmoidal sinus as well as age (p<0.001, r = 0.71). Proptosis reduction could not be predicted by tissue prolapse, defect length or depth of ethmoidal sinus. The abduction deficit correlated significantly with tissue prolapse and orbital surface area (p<0.001, r = 0.37) but not with the horizontal muscle diameter.

CONCLUSION

We were able to show that orbital morphology influences the outcome of balanced orbital decompression surgery in terms of proptosis reduction and motility. However, the rather low coefficients of correlation show that the surgical outcome cannot be predicted with simple CT measurements, although risk factors for postoperative abduction deficit could be found. Therefore, preoperative planning should consider especially the orbital surface area and depth of ethmoidal sinus. Patients should be informed about the higher risk of diplopia with higher proptosis reduction.

Radiotherapy for Active Thyroid Eye Disease

PURPOSE

To critically review the published literature on orbital radiotherapy as a treatment modality for thyroid eye disease (TED).

METHODS

A systematic review and analysis of the relevant published literature was performed.

RESULTS

Thyroid eye disease is an autoimmune condition that is amenable to treatments that modulate the immune response, including orbital radiotherapy (ORT). Ideal candidates for ORT are patients in the early, active phase of TED with moderate to severe, or rapidly progressive, disease, including patients with significant motility deficits and compressive optic neuropathy. Patients with progressive strabismus may also benefit. Patients with mild or inactive disease will not benefit from ORT when compared with the natural history of the disease. Orbital radiotherapy should generally be used in conjunction with corticosteroid therapy, with response to corticosteroids demonstrating the immunomodulatory therapeutic potential of ORT. When treating TED-compressive optic neuropathy, ORT may help obviate the need for urgent surgical decompression, or postpone it until the stable, inactive phase of the disease. Orbital radiotherapy treatment doses should approach 20 Gy in most cases, but lower doses may be considered in younger patients without significant dysmotility. The safety profile of ORT is well established, and side effects are minimal in appropriately selected patients.

CONCLUSIONS

Radiotherapy is a safe and effective treatment for active TED in appropriately selected patients.

Orbital Radiotherapy Combined With Corticosteroid Treatment for Thyroid Eye Disease-Compressive Optic Neuropathy

PURPOSE

To evaluate the effectiveness of orbital radiotherapy (ORT) in the treatment of thyroid eye disease (TED)-compressive optic neuropathy.

METHODS

A retrospective review of patients with corticosteroid-responsive compressive optic neuropathy due to TED treated with ORT. Study was conducted in compliance with Health Insurance Portability and Accountability Act. One hundred four patients (163 orbits) with a mean age of 61.7 years met inclusion criteria. Seventy-four percent (77/104) were female, and 32.7% (34/104) were current or previous smokers. A total absorbed dose of 2000 cGy fractionated in 10 treatment doses over the course of 2 weeks was administered to the retroocular tissues according to a standard protocol. The primary end point was failure of ORT, defined as persistent optic neuropathy following completion of radiotherapy that mandated urgent orbital decompression surgery.

RESULTS

Ninety-eight of 104 (94%) patients or 152 of 163 (93.3%) orbits did not require orbital decompression surgery during the acute phase. Patients who responded successfully to ORT had similar improvements in visual acuity, color vision, Humphrey threshold visual field testing, and afferent pupillary defects compared with patients who failed ORT and underwent urgent decompression surgery. Only 36.7% of successfully treated patients ultimately underwent elective surgery, including orbital decompression, strabismus, or eyelid surgery, during the inactive phase of TED.

CONCLUSIONS

The data from this study, the largest retrospective review reported to date, supports the use of ORT in eyes with corticosteroid-responsive TED-compressive optic neuropathy. ORT may favorably alter the natural history of active-phase TED by preventing recurrent compressive optic neuropathy after withdrawal of corticosteroids.

Active Moderate-to-Severe Graves' Orbitopathy in a Patient With Type 2 Diabetes Mellitus and Vascular Complications

Background: Graves' orbitopathy (GO) is the main extrathyroidal manifestation of Graves' disease (GD). Diabetes mellitus (DM) has been reported to be a risk factor in patients with GO. Moreover, GO can be more frequent and severe in type 2 diabetes patients. High doses of intravenous glucocorticoids represent the first line treatment of moderate-to-severe and active GO according to the international guidelines. However, this therapy is contraindicated in uncontrolled diabetes and in patients with increased cardiovascular risk. Some anti-diabetic drugs can exacerbate GO. We reported the clinical case of an active and moderate-to-severe GO in a patient with uncontrolled type 2 DM and vascular complications. Case Report: A 61-years-old patient came to our ambulatory for a recurrence of GD and a moderate-to-severe bilateral GO. The patient had uncontrolled type 2 DM during insulin therapy and a history of micro and macrovascular complications. At the physical examination, the clinical activity score was 5 and the severity of GO was moderate-to-severe. A blood sample showed overt hyperthyroidism and the persistence of anti-TSH receptor antibodies (TRAb) during treatment with methimazole. A computed tomography scan showed a moderate-to-severe bilateral exophthalmos. We discuss the benefit/risk of treatment of GO in our patient. Conclusion: The available guidelines do not focus on the treatment of diabetic patients with uncontrolled diabetes and severe vascular complications, therefore our patient represents a difficult therapeutic challenge. The screening of thyroid function and the evaluation of GO could be useful in diabetic patients with autoimmune thyroid disease to perform a correct treatment of these disorders.

Combination Therapy of Intravenous Steroids and Orbital Irradiation is More Effective Than Intravenous Steroids Alone in Patients with Graves' Orbitopathy

The aim of this study was to evaluate and compare the efficacy of intravenous (iv) glucocorticoids (GCs) with and without orbital radiotherapy (ORT) in a retrospective analysis of patients with active, moderate-to-severe Graves' orbitopathy (GO). Since diplopia has the strongest impact on quality of life, a careful work up of motility and binocular single vision (BSV) has been performed. The Essen-EUGOGO-Center database (n=3655) was screened for patients with untreated moderate-to-severe, active GO, onset ≤12 months. The inclusion criteria were met by 148 patients (n=76 ivGC, n=72 ivGC + ORT). We analyzed CAS (inactivation: ≤2), NOSPECS, lid-width, proptosis, motility, and field of BSV. To score the overall ophthalmic outcome, a severity-weighted-score (SOS) was compared with an established EUGOGO inflammation-weighted-score (IOS). Cumulative ivGCs dosages and duration of GO did not differ between the groups. Patients with combination therapy had a significantly more severe GO at baseline. Therefore, a subgroup with matched severity was additionally compared. In the IOS, both groups reached similar improvement rates (55.2 vs. 63.9%; p=0.31). However, in the SOS, the rates differed significantly (46.1 vs. 61.1%; p=0.03- unmatched and p=0.03 matched), despite similar rates of inactivation (65.8 vs. 63.8%). Impaired motility improved significantly more often after combination therapy (p=0.01 matched, p=0.004 unmatched). Treatment responders showed only partial improvement (proptosis: 2.5±0.5 mm; motility: 11.3±10.9°). In our retrospective analysis, combination therapy (ivGCs + ORT) was significantly more effective in reduction of severity and should therefore always be considered in moderate-to-severe GO stages, especially in the presence of motility disorders. However, the limited improvement in clinical parameters, despite the promising effect on inactivation of inflammation, has to be outlined to the patients.

Radiotherapy for Graves' disease. The possible role of low-dose radiotherapy

Immunomodulatory effects of low-dose radiotherapy (LD-RT) have been used for the treatment of several benign diseases, including arthrodegenerative and inflammatory pathologies. Graves' disease is an autoimmune disease and radiotherapy (RT) is a therapeutic option for ocular complications. The dose recommended in the clinical practice is 20 Gy (2 Gy/day). We hypothesized that lower doses (<10 Gy total dose, <1 Gy/day) could results in higher efficacy if we achieved anti-inflammatory and immunomodulatory effects of LD-RT. We review current evidence on the effects of RT in the treatment of Graves' disease and the possible use of LD-RT treatment strategy.

The 2016 European Thyroid Association/European Group on Graves' Orbitopathy Guidelines for the Management of Graves' Orbitopathy

Graves' orbitopathy (GO) is the main extrathyroidal manifestation of Graves' disease, though severe forms are rare. Management of GO is often suboptimal, largely because available treatments do not target pathogenic mechanisms of the disease. Treatment should rely on a thorough assessment of the activity and severity of GO and its impact on the patient's quality of life. Local measures (artificial tears, ointments and dark glasses) and control of risk factors for progression (smoking and thyroid dysfunction) are recommended for all patients. In mild GO, a watchful strategy is usually sufficient, but a 6-month course of selenium supplementation is effective in improving mild manifestations and preventing progression to more severe forms. High-dose glucocorticoids (GCs), preferably via the intravenous route, are the first line of treatment for moderate-to-severe and active GO. The optimal cumulative dose appears to be 4.5-5 g of methylprednisolone, but higher doses (up to 8 g) can be used for more severe forms. Shared decision-making is recommended for selecting second-line treatments, including a second course of intravenous GCs, oral GCs combined with orbital radiotherapy or cyclosporine, rituximab or watchful waiting. Rehabilitative treatment (orbital decompression surgery, squint surgery or eyelid surgery) is needed in the majority of patients when GO has been conservatively managed and inactivated by immunosuppressive treatment.