Methylprednisolone and Graves' ophthalmopathy

Future Projections in Thyroid Eye Disease

BACKGROUND AND AIMS

This review aims to summarize current and emerging therapies for treatment of thyroid eye disease (TED), in the light of novel understanding of pathogenetic mechanisms, leading to new treatment options and clinical trials.

METHODS

We reviewed and analyzed peer-reviewed literature reporting recent translational studies and clinical trials in the treatment of TED. Searches were made at www.pubmed.gov with keywords "thyroid eye disease," "Graves' ophthalmopathy," "thyroid orbitopathy," and "Graves' orbitopathy."

RESULTS

Surgery is reserved for rehabilitation in chronic TED or for emergent compressive optic neuropathy. Oral and intravenous glucocorticoid therapy has been used for decades with variable efficacy in acute TED, but results may be temporary and side effects significant. Nonsteroidal oral immunosuppressive agents offer modest benefit in TED. Several immunomodulatory monoclonal antibodies, including rituximab and tocilizumab, have shown efficacy for inactivating TED. Recently, teprotumumab, an insulin-like growth factor 1 receptor (IGF-1R) inhibitor, has demonstrated significant improvement in proptosis, clinical activity score, diplopia, and quality of life in patients with active TED, with good tolerability. Newly proposed TED therapies, currently in preclinical and clinical trial phases, include thyroid-stimulating hormone (TSH) receptor inhibitory drugs, RVT-1401, local anti-vascular endothelial growth factor therapy, IGF-1R drugs delivered subcutaneously and orally, and desensitization to the TSH receptor with modified TSH receptor peptides.

CONCLUSION

New, albeit incomplete, understanding of the molecular mechanisms of TED has led to new promising therapies and offered improved outcomes in TED patients. Their full role and their relationship to classical immune suppression should be clarified over the next few years.

Thyroid eye disease

Thyroid eye disease (TED) is the most common cause of proptosis in adults, and should always be a consideration in patients with unexplained diplopia, pain, or optic nerve dysfunction. At least 80% of TED is associated with Graves disease (GD), and at least 50% of patients with GD develop clinically evident symptomatic TED. The most confusing patients for doctors of all subspecialties are the patients with eye symptoms and signs that precede serum evidence of a thyroid imbalance. Management of TED may include immunosuppressive medications, radiation, or surgery. Although the prognosis for optic nerve function is excellent, the restrictive dysmotility can result in permanent disability. Orbit and eyelid reconstruction are reserved for stable, inactive patients and are the final steps in minimizing facial alterations and enhancing the patient's daily functioning.

Efficacy of corticosteroids and external beam radiation in the management of moderate to severe thyroid eye disease

Thyroid Eye Disease (TED, Graves ophthalmopathy, thyroid ophthalmopathy) is the most common cause of orbital inflammation and proptosis in adults. There is no agreement on its management although corticosteroids and external beam orbital radiation (XRT) have traditionally been believed to provide benefit in active inflammation. Our review of the published literature in English disclosed an overall corticosteroid-mediated treatment response of 66.9% in a total of 834 treated patients who had moderate or severe TED. Intravenous corticosteroids used in repeated weekly pulses were more effective (overall favorable response = 74.6%, n = 177) and had fewer side effects than daily oral corticosteroids (overall favorable response = 55.5%, n = 265). A combination of corticosteroid and radiation therapy seemed to be more effective than corticosteroids alone. Our conclusions are tempered by a notable lack of standardization within and between study designs, treatment protocols, and outcome measures. Accordingly, the North American Neuro-Ophthalmology Society (NANOS), American Society of Ophthalmic Plastic and Reconstructive Surgery (ASOPRS) and the Orbital Society, in conjunction with Neuro-Ophthalmology Research and Development Consortium (NORDIC), will investigate the design and funding of a multi-center controlled trial.

Comparison of the effectiveness and tolerability of intravenous or oral glucocorticoids associated with orbital radiotherapy in the management of severe Graves' ophthalmopathy: results of a prospective, single-blind, randomized study

Eighty-two consecutive patients with moderate-to-severe and active Graves' ophthalmopathy were randomly treated with orbital radiotherapy combined with either oral (prednisone; starting dose, 100 mg/d; withdrawal after 5 months) or iv (methylprednisolone; 15 mg/kg for four cycles and then 7.5 mg/kg for four cycles; each cycle consisted of two infusions on alternate days at 2-wk intervals) glucocorticoids. The two groups did not differ for age, gender, duration of hyperthyroidism and ophthalmopathy, prevalence of smokers, thyroid volume, and pretreatment ocular conditions. Both groups of patients received radioiodine therapy shortly before treatment for Graves' ophthalmopathy. Follow-up lasted for 12 months. A significant reduction in proptosis (from 23.2 +/- 3.0 to 21.6 +/- 1.2 mm in the iv glucocorticoid group, P < 0.0001; and from 23 +/- 1.8 to 21.7 +/- 1.8 mm in oral glucocorticoid group, P < 0.0001) and in lid width (from 13.3 +/- 2.5 to 11.8 +/- 2.2 mm, and from 13.6 +/- 2.0 to 11.5 +/- 1.9 mm, respectively; P < 0.001 in both cases) occurred, with no difference between the two groups. Diplopia significantly improved in both groups: it disappeared in 13 of 27 (48.1%) iv glucocorticoid patients (P < 0.005) and in 12 of 33 (36.4%) oral glucocorticoid patients (P < 0.03). The degree of amelioration of diplopia did not significantly differ between the two groups (P = 0.82). Optic neuropathy improved in 11 of 14 iv glucocorticoid (P < 0.01) and only in 3 of 9 oral glucocorticoid (P = 0.57) patients, with no significant difference in these outcomes. The Clinical Activity Score decreased from 4.5 +/- 1.2 to 1.7 +/- 1.0 (P < 0.0001) in the iv glucocorticoid group and from 4.2 +/- 1.1 to 2.2 +/- 1.2 (P < 0.0001) in the oral glucocorticoid group; final Clinical Activity Score was significantly lower in iv glucocorticoid than in oral glucocorticoid patients (P < 0.01). By self-assessment evaluation, 35 (85.3%) iv glucocorticoid and 30 (73.2%) oral glucocorticoid patients reported an improvement of ocular conditions (P = 0.27). Overall, both treatments produced favorable effects in most patients, but responders in the iv glucocorticoid group (36 of 41, 87.8%) were more than in the oral glucocorticoid group (26 of 41, 63.4%) (P < 0.02). Moreover, iv glucocorticoid treatment was better tolerated than oral glucocorticoid treatment. Side effects occurred in 23 (56.1%) iv glucocorticoid and 35 (85.4%) oral glucocorticoid patients (P < 0.01); in particular, cushingoid features developed in 5 of the former and 35 of the latter patients. One iv glucocorticoid patient had severe hepatitis of undetermined origin at the end of glucocorticoid treatment, followed by spontaneous recovery. In conclusion, high-dose iv glucocorticoid and oral glucocorticoid (associated with orbital radiotherapy) are effective in the management of severe Graves' ophthalmopathy, but the iv route seems to be more effective and better tolerated than the oral route and associated with a lower rate of side effects.

Role of magnetic resonance imaging in thyroid-associated ophthalmopathy: its predictive value for therapeutic outcome of immunosuppressive therapy

To investigate the efficacy of magnetic resonance imaging (MRI) in the assessment of thyroid-associated ophthalmopathy (TAO), 51 patients with TAO were evaluated by ophthalmologic examinations and MRI at 0.5 T. Thickness of extraocular muscles (EM) was measured by T1-weighted image. Signal intensities of EM and orbital connective tissue (OCT) were measured by short inversion time inversion recovery (STIR) image and expressed as a ratio by comparison to the signal intensity of cerebral substantia alba (SI, signal intensity ratio). Significant enlargement of one or more EM was observed in 86% of patients with TAO, and SI of EM (2.15 +/- 0.63, mean +/- SD) was significantly increased compared with control values (n = 16; 1.35 +/- 0.33; t test, p < 0.01). SI of OCT tended to be greater than that in the control group, although the difference was not significant. There was a significant positive correlation between thickness of EM and severity of ophthalmopathy, assessed as an ophthalmopathy index (p < 0.05). SI of neither EM nor OCT correlated with the severity of the eye disease. To investigate whether MRI findings could predict the outcome of methylprednisolone pulse therapy, we studied 23 patients with TAO who received this treatment. SI of EM and OCT in the 12 patients giving favorable responses were significantly greater than those in the 11 patients without good response (t test, p < 0.01). On the other hand, the thickness of eye muscles did not correlate with the outcome of treatment except for that of medial rectus muscle. There was a significant correlation between SI of EM and that of OCT (r = 0.78, p < 0.01), suggesting possible similar pathologic processes in these tissues in TAO.(ABSTRACT TRUNCATED AT 250 WORDS)