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.

Upper Eyelid Retraction in Graves' Ophthalmopathy: Our Surgical Experience on 153 Cases of Full-Thickness Anterior Blepharotomy with Mullerectomy.

BACKGROUND: We present our experience on 153 cases of full-thickness anterior blepharotomy with mullerectomy (FTABM) in the treatment of upper eyelid retraction (UER) related to Graves' ophthalmopathy (GO). METHODS: We included all the patients who underwent a graded FTABM between 1st January 2015 and 30th June 2020 for UER GO-related. The analysis included: pre-/post-operative conjunctival symptoms, epiphora, GO-Quality of Life Questionnaire (QoL), lagophthalmos, marginal reflex distance (MRD-1) index, eyelid symmetry within 1mm. The statistical analysis was designed to detect postoperative improvement in objective and subjective clinical features. Outcomes were analysed through Chi-squared test for dichotomous variables and through Wilcoxon-Mann-Whitney test for continuous variables. RESULTS: Of the 111 patients, 42 underwent a bilateral procedure, while 69 a monolateral. Conjunctival symptoms were reported in 32% of cases before surgery and in 12.4% after FTABM (p < 0.001). Epiphora was complained by 29.6% of patients preoperatively and in 12.4% postoperatively (p < 0.001). Preoperative lagophthalmos was found in 12.4% (mean value of 0.34 ± 0.76 mm) of eyelids, and in 2.6% (mean value 0.05 ± 0.19 mm) eyelids (p = not significant) postoperatively. Pre-operative GO-QoL was 24.9 ± 4.4 mm; while post-operative GO-QoL was 35.3 ± 5.5 mm (p < 0.001). The MRD-1 varied from 10.12 ± 2.1 mm preoperatively, to 4.3 ± 0.6 mm (p < 0.001) after surgery. Asymmetric palpebral fissure was noted in 94 (84.7%) patients before surgery and in 7 (6.3%) after the procedure (p < 0.001). CONCLUSION: FTABM is an effective procedure to treat UER GO-related. The technique manages to prevent complications of UER and determine good aesthetics. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 . Level IV, therapeutic study.

Management of upper retropharyngeal abscesses in children: Two case reports of a troublesome situation.

Management of upper retropharyngeal abscesses in children is challenging. In surgical cases, ultrasound-assisted intra-operative procedures may be helpful to reach peculiar locations, thus reducing surgical morbidity and complications rate.

The "Parachute" Technique for the Endoscopic Repair of High-Flow Anterior Skull-Base CSF Leaks.

OBJECTIVE: This study aims to assess the feasibility and reliability of our endoscopic trans-nasal technique for the repair of cribriform and sellar high-flow cerebrospinal fluid (CSF) leaks. METHODS: A comparison between patients suffering from high-flow rhinorrhea and treated through a free grafting endoscopic technique or the "parachute" technique, our nasal packing proposal, was performed. RESULTS: Thirty-three patients were included. The mean age was 52 years (range: 36-68 years). The etiology of the CSF leaks was iatrogenic in 16 cases (48.5%), traumatic in 5 cases (15.2%), spontaneous in 11 cases (33.3%), and related to anterior skull base tumors in 1 case (3%). The bone defect affected the sphenoidal sinus in 20 cases (60.6%), the cribriform plate of the ethmoid in 10 cases (30.3%), and both the sphenoid and ethmoid in 3 cases (9.1%). The mean size of bone defects was 8.5 ± 3.9 mm. The median follow-up was 28 (64) months. A CSF leak recurrence occurred in no cases treated with the parachute technique and in 3 cases that underwent conventional endoscopic treatments. The CSF leak recurrences were associated with 2 iatrogenic and 1 post-traumatic fistula. All the CSF leak recurrences underwent the parachute technique, not showing second recurrences. CONCLUSIONS: Our results suggest that the parachute technique is simple, safe, and effective. We recommend it as an alternative treatment to vascular flaps for the treatment of high-flow and recurrent fistulas.

Efficacy Profile and Safety of Very Low-Dose Rituximab in Patients with Graves' Orbitopathy.

Background: Rituximab (RTX), a chimeric human-murine anti-CD20 monoclonal antibody, has been used for treatment of active moderate-severe Graves' orbitopathy (GO) since 2004 as second-line therapy in patients unresponsive to intravenous steroids. We conducted an open-label prospective study (EUDRACT 2012-001980-53) in which patients were treated with a single infusion of only 100 mg RTX to analyze the efficacy and safety of this low dose. Methods: Seventeen patients, of whom nine had disease that was unresponsive to intravenous methylprednisolone and eight with newly diagnosed GO, were enrolled. Disease activity was assessed with the clinical activity score (CAS) and severity with a composite ophthalmic score. Long-term surgical treatment and quality of life were also assessed, as well as treatment-related adverse events. Results: Mean baseline CAS was 4.56 ± 0.96 and decreased to 1.25 ± 1.14 at 24 weeks (p = 0.001). Disease inactivation occurred within 24 weeks in >90% of patients and was unrelated to disease duration. Severity improved in about 60% of patients, with no relapses. All patients showed peripheral depletion of CD20+ and CD19+ cells at the end of RTX infusion (60 minutes). Two patients required surgical orbital decompression because of optic neuropathy (ON). Among adverse events observed, there was one patient who developed a cytokine release syndrome. Conclusions: A dose of 100 mg RTX is effective in patients with active moderate-severe GO. Low doses are better tolerated, expose patients to immune suppression for a shorter period of time, and are extremely cost effective, compared with higher doses. This dose, consistently with all other immunosuppressants, does not prevent the progression of GO to dysthyroid ON.

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.

Therapy With Different Dose Regimens of Rituximab in Patients With Active Moderate-To-Severe Graves' Orbitopathy.

Background: Immunosuppressive therapy of Graves' orbitopathy (GO) is indicated during the active phase of disease. Intravenous steroids (IVGC) are effective in about 70% of patients, although unresponsiveness or relapse are observed. In previous studies, rituximab (RTX) has been shown to be effective in inactivating moderate-to-severe GO when used early in the disease, but its optimal dosage has never been studied in randomized clinical trials. Aim of this study was to compare the efficacy and safety of different doses of RTX, based on a post-hoc analysis of two open label studies and one prospective trial randomized to IVGC. Methods: of 40 patients (35 women, 5 men), with active moderate-to-severe GO treated with RTX, 14 received a single dose of 100 mg (Group 1), 15 a single dose of 500 mg (Group 2) and 11 two 1000 mg doses, administered one week apart (Group 3). Thyroid function, TSH-receptor antibodies (TRAb) and peripheral CD19+ cells were measured. Primary endpoint was disease inactivation, measured as a decrease of the Clinical Activity Score (CAS) of at least two points. Secondary endpoints were improvement of proptosis, diplopia, quality of life and safety. Results: Baseline CAS decreased significantly in all groups (P<0.0001), independently of GO duration or whether patients had newly occurring or relapsing GO after IVGC. Proptosis did not significantly change. There was an inverse correlation between the Gorman score for diplopia and RTX dose (P<0.01). The appearance score of the GO-QoL improved in Group 1 (P=0.015), and the visual function score, in Group 2 (P=0.04). A reduction of serum TRAb was observed in Group 1 (P=0.002) and Group 2 (P<0.0002), but not in Group 3. CD19+ cell decreased in all groups (P<0.01), independently of the dose. Conclusions: We studied the optimal dosage of RTX in the treatment of active moderate-to-severe GO. In this analysis, we considered the efficacy of RTX in inactivating GO, in changing its natural course, its effect on disease severity and on the patients' quality of life. Based on our clinical findings, and balancing the cost of therapy, a single 500 mg dose regimen is suggested in the majority of patients.

Abscess of the clivus in an adolescent with complicated acute rhinosinusitis: a case report.

BACKGROUND: Complications of acute sinusitis affecting multiple sites are very uncommon, and generally develop for a delayed diagnosis of the primary infection, with possible severe and life-threatening evolution. Patients can have variable presentations according to the site and extent of the infection. Multiple forms generally include the coexistence of orbital manifestations and intracranial infections. We here present a case with unusual multiple sites locations (i.e.: intraorbital intraconic abscess, sigmoid sinus thrombosis, preclival abscess, multiple splanchnocranium osteomyelitic processes). CASE PRESENTATION: A 13-year-old male presented at our hospital with right progressive orbital oedema with eyesight worsening and signs of meningitis. Computed tomography and magnetic resonance (MRI) demonstrated right intraorbital intraconic abscess, left sphenoidal sinusitis, transverse and sigmoid sinus thrombosis. Ophthalmologic evaluation documented a right optic nerve sufferance. Endoscopic and superior right trans-palpebral surgical decompression was performed, and the abscess was drained. Microbiological analysis revealed the presence of multi-sensitive Streptococcus Intermedius. Subsequent prolonged antibiotic and anti-thrombotic treatments were started. In the following two-weeks the sinusal and ophthalmologic clinical conditions improved, whereas the patients complained of mild to moderate cervical pain and suffered from intermittent pyrexia. Control MRI documented clival abscess extending up to preclival soft tissues posterior to the nasopharynx, associated with mandible osteomyelitis, occipital condyles and anterior part of the temporal bone hyper intensity. Endoscopic trans-nasal surgical approach to the clival compartment with neurosurgery navigation-guided achieved preclival abscess drainage. Complete clinical and radiological recovery was achieved after 45 days of medical treatment. CONCLUSIONS: Multiple sites complicated rhinosinusitis is uncommon, and its management is challenging. A proper history and thorough clinical examination along with a radiological evaluation are key factors in the final diagnosis of patients with complicated multiple sites acute rhinosinusitis. A quick multidisciplinary approach is always necessary to avoid unwanted life-threatening complications.

The suprasellar volume of nonfunctioning pituitary adenomas: a useful tool for predicting visual field deficits.

PURPOSE: The aim of the present study is to assess the predictive value of the suprasellar volume (SSV) of nonfunctioning pituitary adenomas (NFPAs) for visual field (VF) impairment in order to guide clinical decision-making and improve neurosurgical management. METHODS: Two independent samples of patients with NFPAs (exploratory population N = 50, testing population N = 98) were included in the present study. In the first phase, we determined the optimal cut-off value of the SSV correlating with VF deficits in the exploratory population. In the second phase, we then studied the accuracy of identified cut-off in predicting a VF deficit in the testing population. RESULTS: In the exploratory population, the optimal cut-off value of the SSV to determine the presence of a VF deficit was 1.5 mL. Sensitivity and specificity of the cut-off were 81.3 and 100%, respectively. The positive predictive value (PPV) and the negative predictive value (NPV) were 100 and 75%, respectively. When we checked the identified cut-off score on the testing population, we found a sensitivity of 71% and a specificity of 100%. The PPV and NPV were 100 and 59.2%, respectively. In six cases with VF defects and SSV inferior to 1.5 mL, the displacement of optic chiasm was in superior position. CONCLUSION: The SSV may represent an accurate method in routinely clinical practice for predicting VF deficit in patients affected by NFPA.

Prevention of Orbitopathy by Oral or Intravenous Steroid Prophylaxis in Short Duration Graves' Disease Patients Undergoing Radioiodine Ablation: A Prospective Randomized Control Trial Study.

Background: Radioiodine (RAI) is a known risk factor for activation or de novo occurrence of Graves' orbitopathy (GO). Several studies demonstrated that GO can be prevented by glucocorticoids (GCs) in patients with pre-existing GO. We have previously shown that Graves' disease duration (GDd) <5 years is a risk factor for RAI-induced GO. We studied the effect of prophylaxis with either oral GCs (OGCs) or intravenous GCs (IVGCs) on GO activation in patients with GDd. Methods: In total, 99 hyperthyroid patients without GO or with pre-existing inactive GO with GDd <5 years were randomized to receive IVGCs (N = 49) or OGCs (N = 50) before RAI; 22 patients with GDd >5 did not receive steroids and were studied as controls. All patients underwent ophthalmological assessment before and 45, 90, 180 days and for a 5-year follow-up after RAI. Serum thyrotropin (TSH) receptor antibodies (TRAbs), thyroid hormones, and thyroid volume (TV) were also measured in response to RAI therapy and steroid prophylaxis. Results: No patient on prophylaxis developed GO after RAI. One woman of the control group, without steroid prophylaxis, and who had a marked elevation of her TSH, showed transient reactivation of GO, which spontaneously improved after restoring euthyroidism. On follow-up at 12 and 20 months after RAI, two patients developed overt optic neuropathy. A smaller TV was associated with a higher prevalence of RAI-induced hypothyroidism. Serum TRAbs increased significantly after RAI (p < 0.0001) but less in patients receiving steroids than in those without prophylaxis at 45 days (p < 0.01). Conclusions: The risk of RAI-induced GO can be prevented in all patients with GDd <5 years by steroids. Such treatment may not be necessary in patients with GDd >5 years. The blunting of TRAb elevation after RAI may be related to the prophylactic effect of steroids.

Review of Systemic Antibiotic Treatments in Children with Rhinosinusitis.

Antibiotic treatment in paediatric rhinosinusitis is still a matter of debate, as the current guidelines have been drafted mainly based on clinical studies published before 2013. Recent modifications in the epidemiological basis of the disease might mean that current treatments are not completely adequate considering the evolving microbiological profile of the disease. The present paper reviews the role of systemic antibiotics in children with acute (ARS), chronic (CRS), recurrent (RARS), and complicated acute (CoARS) rhinosinusitis. A total of 14 studies (including 3 prospective non-randomised studies, 8 retrospective studies, and 3 prospective randomised studies) of the 115 initially identified papers were included in this review, corresponding to 13,425 patients. Five papers dealt with ARS, four papers with RARS or CRS, and five papers with CoARS; the remaining papers included patients with either ARS or CRS. Data about the effectiveness of antibiotic treatment in children with ARC, CRS, and CoARS is scarce, as only three randomised controlled trials have been published in the last decade, with contrasting results. There is an urgent need for dedicated controlled trials not only to test the actual clinical benefits deriving from the routine use of systemic antibiotics in different categories of patients but also to compare the effectiveness of various therapeutic protocols in terms of the type of antibacterial molecules and the duration of treatment.

Surgical Treatment of Paediatric Chronic Rhinosinusitis.

Rhinosinusitis (RS) is a common disease in children, significantly affecting their quality of life. Chronic rhinosinusitis (CRS) is frequently linked to other respiratory diseases, including asthma. Children affected by CRS may be candidates for surgery in the case of failure of maximal medical therapy comprising three to six weeks of broad-spectrum systemic antibiotics with adjunctive therapies. Although endoscopic sinus surgery (ESS) is the surgical treatment of choice in adult patients with CRS, different surgical procedures are scheduled for refractory paediatric CRS and include adenoidectomy, paediatric ESS (PESS), and balloon catheter sinuplasty (BCS). The present paper discusses the indications and limitations of each treatment option in children with CRS. Given the amount of current evidence, it is reasonable to suggest that, in young and otherwise healthy children with refractory CRS, an adenoidectomy (eventually combined with BCS) should be offered as the first-line surgical treatment. Nevertheless, this approach may be considered ineffective in some patients who should be candidates for traditional ESS. In older children, those with asthma, or in the case of peculiar conditions, traditional ESS should be considered as the primary treatment.

Sinonasal-Related Orbital Infections in Children: A Clinical and Therapeutic Overview.

Sinonasal-related orbital infections (SROIs) are typically pediatric diseases that occur in 3⁻4% of children with acute rhinosinusitis. They are characterised by various clinical manifestations, such as peri-orbital and orbital cellulitis or orbital and sub-periosteal abscesses that may develop anteriorly or posteriorly to the orbital septum. Posterior septal complications are particularly dangerous, as they may lead to visual loss and life-threatening events, such as an intracranial abscess and cavernous sinus thrombosis. Given the possible risk of permanent visual loss due to optic neuritis or orbital nerve ischemia, SROIs are considered ophthalmic emergencies that need to be promptly recognised and treated in an urgent-care setting. The key to obtaining better clinical outcomes in children with SROIs is a multi-disciplinary assessment by pediatricians, otolaryngologists, ophthalmologists, radiologists, and in selected cases, neurosurgeons, neurologists, and infectious disease specialists. The aim of this paper is to provide an overview of the pathogenesis, clinical manifestations, diagnosis, and treatment of pediatric SROIs, and to make some practical recommendations for attending clinicians.

Aneurysmal bone cyst in the inferior nasal turbinate in a pediatric patient: A case report.

Torretta S, Di Pasquale D, Carioli D, Guastella C, Ibba T, Marchision P, Pignataro L. Aneurysmal bone cyst in the inferior nasal turbinate in a pediatric patient: A case report. Turk J Pediatr 2018; 60: 747-750. Aneurysmal bone cysts (ABCs) are non-neoplastic, highly vascularised bone lesions that rarely involve the craniofacial complex. We describe the first case of an ABC involving the inferior turbinate in a 17-month-old boy who attended our Pediatric Emergency Department because of recurrent epistaxis, and discuss the diagnostic and therapeutic work-up in children with nasal masses.

Is Complex Sphenoidal Sinus Anatomy a Contraindication to a Transsphenoidal Approach for Resection of Sellar Lesions? Case Series and Review of the Literature.

BACKGROUND: The transsphenoidal approach is considered the gold standard for resection of pituitary adenomas and other sellar region lesions. This approach is guided by a few fundamental anatomic landmarks that conduct the surgeon toward the sellar floor. Some anatomic structures may vary a lot (e.g., intrasphenoidal septa, intercarotid distance) and may be difficult to identify. Pneumatization and conformation of the sphenoidal sinus (SS) plays a key role in accessing the floor of the sella and other skull base structures. A poorly pneumatized SS may be a relative contraindication to the transsphenoidal approach. We analyzed outcome and complications in transsphenoidal surgery for sellar lesions with a difficult SS. METHODS: We analyzed 243 consecutive patients who underwent a transsphenoidal approach for sellar lesions. Patients with poor pneumatization of the SS were included. Neurosurgical and endocrinologic outcomes were reported. RESULTS: Successful treatment using a transsphenoidal approach with neuronavigation and Doppler ultrasound was achieved in 15 patients with a low degree of pneumatization of the SS. A pituitary adenoma was present in 13 of 15 patients. Endocrinologic and neurosurgical outcomes were similar to patients with normal pneumatization of the SS, showing a cure of disease in 6 of 9 patients with functioning adenomas and an improvement of symptoms in cases of nonfunctioning adenomas. CONCLUSIONS: Patients with a poorly pneumatized SS can be treated safely with a transsphenoidal approach using image guidance techniques to avoid major neurovascular complications.

Efficacy of B-cell targeted therapy with rituximab in patients with active moderate to severe Graves' orbitopathy: a randomized controlled study.

BACKGROUND: Preliminary studies have shown that rituximab (RTX) is effective in the treatment of active Graves' orbitopathy (GO). METHODS: We conducted a double-blind, randomized trial (European Clinical Trials Database [EudraCT] 2007-003910-33) to compare RTX with iv methylprednisolone (ivMP) in patients with active moderate to severe GO. Thirty-two patients were randomized to receive either ivMP (7.5 g) or RTX (2000 or 500 mg). The primary end point was the decrease of the clinical activity score of 2 points or to less than 3 at week 24. Changes of proptosis, lid fissure, diplopia and eye muscle motility, and quality of life score were secondary end points. The number of therapeutic responses, disease reactivation, and surgical procedures required during follow-up and the patients' quality of life were also assessed. RESULTS: The clinical activity score decreased with both treatments but more after RTX at 16, 20, and 24 weeks (P < .04, P < .02, P < .006, respectively), whether 1000 mg RTX twice or 500 mg RTX once was used (P = NS). At 24 weeks 100% of RTX patients improved compared with 69% after ivMP (P < .001). Disease reactivation was never observed in RTX patients but was observed in five after ivMP. Patients treated with RTX scored better motility at 52 weeks in both the right (P = .014) and the left eye (P = .026). Overall rehabilitative surgical procedures carried out during follow-up (at 76 wk) were 12 in 16 ivMP patients and 5 in 15 RTX patients (P = .049). CONCLUSIONS: The results of this trial confirm preliminary reports on a better therapeutic outcome of RTX in active moderate to severe GO, when compared with ivMP, even after a lower RTX dose. The better eye motility outcome, visual functioning of the quality of life assessment, and the reduced number of surgical procedures in patients after RTX seem to suggest a disease-modifying effect of the drug.

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.