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Updated: Jan 15, 2026
Transoral Endoscopic Thyroidectomy Vestibular Approach for Thyroid Lobectomy
Published on: May 12, 2023
A comparative study of the characteristics and prognosis of orbital myositis versus thyroid-associated orbitopathy
Augustin Lecler1, Alistair Baber2, Marie Callet3
1Neuroradiology Department, Hopital Fondation Adolphe de Rothschild, Paris, France.
Purpose:
To compare the clinical presentation, imaging features and outcomes of patients with orbital myositis (OM) and thyroid associated orbitopathy (TAO).
Methods:
A retrospective and comparative study of 60 patients diagnosed with OM in a tertiary Eye Clinic between 2012 and 2023. Cases were matched with 60 TAO controls by sex and age.
Results:
Clinical presentation of OM differs from TAO with a unilateral involvement and an acute onset of symptoms in 93% and 65% of cases, respectively. OM usually affect a single extraocular muscle (63%), typically the medial rectus, whereas TAO affect multiple and several EOM, with higher incidence of increased orbital fat volume. Tendon sparing on MRI was not discriminant between both conditions. Patients with OM had a better remission rate at 12 months (48% vs 14%, p < 0.001). Optic neuritis occurred in only one patient with OM vs. 11 patients with TAO (p < 0.001) and 12 patients had a relapse of OM with a contralateral involvement in 3/12 patients (25%).
Conclusions:
This comparative study highlights key clinical and imaging features that distinguish OM from TAO. OM is associated with a better clinical outcome and prognosis with a reduced risk of optic neuritis and relapse compared with TAO patients.
