上転障害以外に眼所見が乏しかった甲状腺眼症の2例

Two cases of thyroid-associated ophthalmopathy with impaired upward gaze as the chief ocular finding

要約　目的：上転障害を主な眼症状とする甲状腺眼症の2症例の報告。症例と所見：それぞれ65歳と67歳男性で，1例には1か月前から複視があり，左眼上転障害のみがあった。眼窩の磁気共鳴画像検査（MRI）で下直筋と内直筋の腫大があり，甲状腺眼症と診断された。他の1例は4年前に他医で右眼の動眼神経麻痺と診断されていた。右眼の上転障害のみがあり，MRIで右下直筋の腫大があり，甲状腺眼症と診断された。結論：甲状腺眼症には眼球運動障害が主症状である症例がある。眼球運動障害の原因精査では，MRIを含む眼窩の画像診断が重要である。

Abstract.　Purpose：To report two cases of thyroid-associated ophthalmopathy with restricted upward gaze as the chief ocular manifestation. Cases and Findings：Both were males aged 65 and 67 years respectively. One case had diplopia since one month before with restricted upward gaze as the sole ocular symptom. Magnetic resonance imaging（MRI）showed swelling of medial and inferior rectus muscles,leading to the diagnosis of thyroid ophthalmopathy. The other case had been diagnosed with oculomotor palsy 4 years before. He showed restricted upward gaze as the sole ocular symptom. MRI showed swelling of right inferior rectus muscle. He was diagnosed with thyroid ophthalmopathy. Conclusion：These cases illustrate that impaired ocular movement may be the sole ocular finding in thyroid ophthalmopathy. Diagnostic imaging,including MRI of the orbit,may be crucial in the identification of the underlying cause.