Dysthyroid optic neuropathy: emerging treatment strategies

Abstract

Purpose Dysthyroid optic neuropathy (DON) is a rare sight-threatening complication of Graves’ disease. First-line treatment for DON consists of high-dose intravenous methylprednisolone (ivMP), followed by immediate orbital decompression (OD) if the response is poor or absent as recommended by the 2021 European Group on Graves’ orbitopathy guidelines. The safety and efficacy of the proposed therapy have been proven. However, consensus regarding possible therapeutic options for patients with contraindications to ivMP/OD or resistant form of disease is missing. This paper aims to provide and summarize all available data regarding possible alternative treatment strategies for DON. Methods A comprehensive literature search within an electronic database was performed including data published until December 2022. Results Overall, 52 articles describing use of emerging therapeutic strategies for DON were identified. Collected evidence indicates that biologics, including teprotumumab and tocilizumab, may be considered as an important possible treatment option for DON patients. Rituximab should be avoided in DON due to conflicting data and risk of adverse events. Orbital radiotherapy could be beneficial for patients with restricted ocular motility classified as poor surgical candidates. Conclusion Only a limited number of studies have been dedicated to the therapy of DON, mostly retrospective with a small sample size. Clear criteria regarding diagnosis and resolution of DON do not exist, which restricts comparison of therapeutic outcomes. Randomized clinical trials and comparison studies with long-term follow-ups are necessary to verify the safety and efficacy of each therapeutic option for DON.

Ophthalmology and oculoplastics for the rhinologist

“…Advancement in surgical instrumentation has benefited both oculoplastic surgeons and rhinologists. In particular, the adoption of endoscopic surgery techniques has expanded the surgical access of both specialties ], or provide decompression of the orbital apex in thyroid eye disease orbitopathy [16,17], either for volume expansion or for improvement in optic nerve function. Recently, the advent of transorbital neuroendoscopic surgery (TONES) has provided pathways to intraorbital, sinonasal, and intracranial regions previously inaccessible through external, or even endonasal endoscopic routes [18].…”

“…Thyroid eye disease is a debilitating complication of autoimmune thyroid disease, with a wide range of functional and cosmetic effects. Orbital soft tissue expansion may result proptosis, diplopia, lid retraction, and compressive optic neuropathy [17,25]. Orbital decompression has been the gold standard for orbit expansion/proptosis reduction in affected patients, with endoscopic approaches giving an "invisible" approach to the medial wall [26].…”

“…Orbital decompression has been the gold standard for orbit expansion/proptosis reduction in affected patients, with endoscopic approaches giving an "invisible" approach to the medial wall [26]. In cases of optic nerve compromise, steroids are used concurrently [17]. In almost all cases except for the most fulminant, surgery should only proceed when the disease is no longer in an active inflammatory phase, usually 2-3 years after symptom onset.…”

“…Access to deep structures such as the orbital apex have become commonplace via endoscopic endonasal approach and endoscopic transorbital approaches [15 ▪▪ ]. Endoscopic endonasal surgery may access medial orbit pathology [15 ▪▪ ], or provide decompression of the orbital apex in thyroid eye disease orbitopathy [16,17], either for volume expansion or for improvement in optic nerve function. Recently, the advent of transorbital neuroendoscopic surgery (TONES) has provided pathways to intraorbital, sinonasal, and intracranial regions previously inaccessible through external, or even endonasal endoscopic routes [18].…”

“…Teprotumumab has been considered by some as a “medical” orbital decompression [25]; if possible its effect should be maximized before considering surgery. Currently teprotumumab is being investigated as a treatment modality for chronic thyroid eye disease [28 ▪ ], and dysthyroid optic neuropathy [17]. Adverse effects include hearing loss, hyperglycemia, and fatigue, among others, though treatments are generally well tolerated.…”