Clinical and Visual Outcomes of Dysthyroid Optic Neuropathy After Surgical Orbital Decompression.

Background: Current guidelines suggest high-dose steroids as first-line treatment for dysthyroid optic neuropathy (DON). When steroids fail, decompressive surgery is mandatory. Methods: We conducted a single-center, retrospective cohort study in a tertiary care combined Thyroid-Eye clinic in Milan, Italy. We studied 88 orbits of 56 patients that were submitted to surgical orbital decompression to treat DON from 2005 to 2020. Of these, 33 orbits (37.5%) underwent surgery as first-line treatment for DON whereas the other 55 (62.5%) were decompressed after being unresponsive to very high-dose steroids. Previous orbital surgery, concurrent neurological or ophthalmologic diseases, or incomplete follow-up were considered as exclusion criteria from this study. Surgery was considered successful if no further decompression was needed to preserve vision. Pinhole best corrected visual acuity (p-BCVA), color sensitivity, automated visual field, pupil reflexes, optic disk and fundus appearance, exophtalmometry, and ocular motility were studied before and after surgery (1 week, 1, 3, 6, and 12 months). Activity of Graves' Orbitopathy (GO) was graded using a clinical activity score (CAS). Results: Surgery was successful in 77 orbits (87.5%). The remaining 11 orbits (12.5%) needed further surgery to treat DON definitively. All parameters of visual function improved significantly at follow-up and GO inactivated (CAS <3) within 1 month. At 3 months, all 77 responding orbits had p-BCVA >0.63 whereas all of the 11 non-responding orbits had p-BCVA ≤0.63. Visual field parameters and color sensitivity were not associated with response to surgery. High-dose steroid treatment before surgery was associated with a better response rate (96% vs. 73%; p = 0.004). Balanced decompression was associated with a higher response rate compared with medial wall decompression (96% vs. 80%; p = 0.04). A significant inverse correlation was observed between final p-BCVA and the patient's age (r = -0.42; p = 0.0003). Conclusions: Surgical decompression was found to be a very effective treatment for DON. In this study, all clinical parameters improved after surgery and further intervention was rarely needed.

Quantification of Global Ocular Motility Impairment in Graves' Orbitopathy by Measuring Eye Muscle Ductions.

Background: The overall changes of ocular motility in Graves' orbitopathy (GO) are not easily quantifiable with the methods currently available, especially in clinical studies. The aim of the present study was to calculate parameters that quantify the changes of ocular motility in GO in relation to the Gorman score for diplopia. Methods: We studied 100 GO patients (Group 1) and 100 controls (Group 2). We also included 30 patients treated with intravenous methylprednisolone (iv-MP), assessed at baseline and after 12 and 24 weeks (Group 3), and 66 patients submitted to squint surgery, assessed at baseline and after 12 weeks (Group 4). Ocular ductions were measured in four gaze directions by a perimeter arc and were used to calculate a total motility score (TMS) as the sum of ductions in each direction; a biocular TMS (b-TMS) as the sum of the TMS of two eyes; and an asymmetry ratio (AR) as the sum of the differences of the corresponding ductions between the two fellow eyes divided by the mean difference found in controls. Quality of life was accessed by a specific questionnaire (Graves' orbitopathy quality of life [GO-QoL] questionnaire). Results: TMS and b-TMS were lower, while AR was higher, in Group 1 compared with controls (p < 0.001). In Group 1, TMS and b-TMS were inversely correlated with the Gorman score (p < 0.001) and AR was higher in patients with constant diplopia compared with the others (p < 0.001). In Group 3, TMS and b-TMS increased after treatment in responders to iv-MP (p < 0.001). In Group 4, TMS and b-TMS improved in all patients after surgery (p < 0.01), while AR and GO-QoL score improved only in those without residual constant diplopia (p < 0.001). Conclusion: We describe a quantitative method to assess eye motility dysfunction in any stage of GO to be used as an outcome measure in clinical studies.

Therapeutic outcomes of high-dose intravenous steroids in the treatment of dysthyroid optic neuropathy.

BACKGROUND: While pulsed intravenous methylprednisolone (iv-MP) has been shown to be effective and well tolerated in moderate to severe Graves' orbitopathy (GO), limited data are available on dysthyroid optic neuropathy (DON). The objective of this retrospective study was to investigate the efficacy of iv-MP in the treatment of DON and to seek parameters predictive of response. METHODS: Twenty-four DON patients (40 eyes) treated with iv-MP from 2007 to 2012 were included in the study. Concurrent neurological or ophthalmologic diseases or signs of corneal exposure were considered as exclusion criteria. Iv-MP was administered daily for three consecutive days and repeated the following week. At six months, eyes not requiring surgery to preserve visual function were considered as responsive to treatment. Visual acuity, color sensitivity, visual field, and optic discs were analyzed at two and four weeks, and at 3, 6, and 12 months after treatment. Activity of GO was graded using a clinical activity score (CAS). Visual and clinical characteristics of the eyes responsive to iv-MP were studied by comparison to those of nonresponsive eyes. RESULTS: At six months, 17 of 40 (42.5%) eyes had complete visual recovery and were spared from surgical decompression. At two weeks, visual acuity, color sensitivity, and visual field improved significantly in almost all eyes, but GO inactivated (CAS<4) only in the eyes that permanently responded to iv-MP (p<0.01). The CAS at two weeks was a good predictor of response (cutoff ≥4; 66.7% sensitivity, 76.9% specificity). Optic disc swelling at diagnosis was highly predictive for unresponsiveness to iv-MP (34% sensitivity, 100% specificity). At baseline, high CAS (cutoff >5; 40.2% sensitivity, 94.1% specificity) and severely altered visual field mean defect (cutoff ≤6.31 dB; 73.9% sensitivity, 58.8% specificity) were associated with unresponsiveness to steroids. No major side effects were observed. CONCLUSIONS: High-dose iv-MP was effective in permanently restoring visual function in about 40% of the eyes treated. When successful, it generally induced inactivation of the orbital disease within two weeks and normalization of visual function within one month. The presence of optic disc swelling at diagnosis and persistent active disease at two weeks were good predictors of unresponsiveness to steroids.

Efficacy of rituximab treatment for thyroid-associated ophthalmopathy as a result of intraorbital B-cell depletion in one patient unresponsive to steroid immunosuppression.

One patient with Graves' hyperthyroidism and ophthalmopathy in its active phase and unresponsive to steroid, was treated with the anti-CD20 monoclonal antibody, rituximab (RTX), as part of an open study. The effect of RTX in the thyroid and the orbital tissues was studied. The ophthalmopathy responded to RTX therapy by ameliorating the eye signs with a decrease in the clinical activity score from 5 to 2 in 3 months, while the patient had peripheral B-cell depletion. Hyperthyroidism did not improve during the 6 months of B-cell depletion and serum TSH-receptor antibodies (TRAb) levels did not significantly change after RTX therapy. Therefore, the patient underwent total thyroidectomy and few B-cells were found in the thyroid tissue specimens. While the patient eye disease remained stable (clinical activity score = 2), we performed corrective orbital decompression and we found absence of lymphocytes in the orbital tissue specimens. We believe that RTX treatment in Graves' disease may cause amelioration of ophthalmopathy by depleting total lymphocytes population in the orbit. The persistence of Graves' hyperthyroidism suggests that a single cycle of RTX does not result in complete lymphocyte depletion in thyroid tissue and thus no decline in serum TRAb was observed.