加齢に関連した斜視の非典型例4例

Four cases of atypical age-related strabismus

要約　目的：加齢に関連して発症した斜視（加齢関連斜視）の非典型例を通して，本疾患の病態を考察する。

症例：側臥位にて複視を自覚する高齢者3症例と，外方回旋斜視のため精確な両眼性融像はできていないが複視を自覚しない1症例。

所見：側臥位で複視を自覚した76，83，85歳の3症例には，1〜3°の上下斜位があった。上斜位側に頭部を傾斜すると複視が出現したが，他の注視・頭位状態では複視は自覚していない。外方回旋斜視の症例は81歳。自覚的外方回旋偏位角は右6°，左4°であり，眼底写真から測定した他覚的回旋偏位角は両眼とも19°であった。比較的良好な近見立体視を保っているが，Bagolini線条レンズで周辺視野は融像できていないことがわかった。

結論：高齢者の小角度上下斜位患者には，頭部傾斜時のみ複視を自覚する例がある。高齢者の純粋回旋斜視患者は複視を自覚しないであろう。

Abstract　Purpose：To discuss about the process of developing age-related strabismus through data from atypical cases.

Case：3 aged patients who notice diplopia only when they lie on one side. 1 aged patient who does not have enough binocular fusion due to excyclotropia and does not notice diplopia.

Findings：76-, 83-, 85-year-old patients noticed diplopia in a recumbent position. They had hyperphoria of 1 to 3 degrees. They all noticed diplopia on lying to the side of hypertropic eye. They had no diplopia in other gaze or head-tilt conditions.

　An 81-year-old lady showed excyclodeviation in both eyes. Angle of subjective excyclotorsion was 6 degrees and 4 degrees in the right and left eye, respectively. Angle of objective excyclotorsion measured from fundus photos was 19 degrees in both eyes. She enjoyed relatively good stereo acuity at near vision, however, Bagolini striated glass test revealed that the peripheral visual field of each eye did not fuse.

Conclusion：Some of the age-related hypertropia patients notice diplopia only when they tilt the head. Aged patient with pure cyclotropia may not notice diplopia.