Inflammation of the eye muscle is called myositis and is associated with a entitiy known as idiopathic inflammatory disease. The cause is typically unknown in most cases and is frustrating for the patient and the physician. Treatment is oral steroid. I haven't tried topical before. Anyway I work these up for other possible causes such and sarcoidosis, lymphoma, wegeners, polyarteritis nodosa, lupus, rheumatoid arthritis, herpes zoster, herpes simplex, thyroid eye disease, other tumors. Recommend blood work, orbital imaging such as a CT and/or MRI. Blood work such as: ana, ace, lysozyme, rpr, vdrl, cbc, bun/cr, renal, lft, thyroid panel, anca). If all negative then consider a muscle biopsy. I offer this to patient who have recurrences or those who initially just want to know. Most cases of myositis responded rapidly to oral steroids and are less likely to have recurrence if the taper of the steroid is slow over 6-8 weeks.