Consecutive cyclic esotropiaの3症例

Three cases of consecutive cyclic esotropia

　間歇性外斜視術後に，周期性内斜視となったconsecutive cyclic esotropia 3症例の臨床所見，手術方法，術後経過について述べ，"primary cyclic esotropia"との比較検討を行った．

　Consecutive cyclic esotropiaの特徴は近視傾向を示し，手術眼の外転抑制を伴うことであり，原因として外直筋の不全麻痺と，手術を契機として生じた外直筋のtonusの変化と，「生物時計」biological clockの関係が考えられた．

We proposed, in 1977, the term consecutive cy-clic esotropia to describe cyclic esotropia after sur-gery for intermittent exotropia. The present paper describes 3 cases with this condition.

Consecutive cyclic esotropia is characterized by myopia and underaction of lateral rectus muscle which was earlier recessed for intermittent exotropia. It is different, therefore, from hypermetropia and primary cyclic esotropia. While its exact cause has not been identified so far, we suspect the damaged lateral rectus muscle due to prior surgery and the possible relationship between this damage and the biological clock.