Visual hand displayによる生後6か月までの視力発達の測定

Visual acuity in infants up to six months after birth measured by visual hand display

要約　目的：手持ち視力測定器（visual hand display：VHD）で測定した生後6か月までの乳児の視力の報告。対象と方法：生後1～36週までの乳児47名を対象とした。男児28名，女児19名で，38例が生後24週未満であった。視力測定には直径20cmの円板の両側に2種類の縞模様が描かれているVHDを使った。これを眼前で動かし，縞模様を追従できるかどうかで視力を決定した。結果：視力は生後4週で0.01，8週で0.016，12週で0.036，16～20週で0.05～0.06であった。この結果は，従来のpreferential lookingまたはTeller acuity cardによる結果とほぼ一致した。結論：VHDによる視力測定法は，生後6か月までの乳児の視機能評価に有用であった。

Abstract.　Purpose：To report the visual acuity in infants up to 6 months after birth. Cases and Method：This study was made on 47 infants from one to 36 weeks after birth. The series comprised 28 male and 19 female babies. Thirty-eight cases were below 24 weeks of age. Visual hand display（VHD）, which is a hand-held disc of 20 cm in diameter, was used to measure the visual acuity. Stripes of different sizes are printed on both sides of the disc. This disc was moved in front of the infant. Visual acuity was calculated by the ability of the infant to follow the stripes. Results：Visual acuity by this method was 0.01 after 4 weeks of birth, 0.016 after 8 weeks, 0.036 after 12 weeks, and 0.05 to 0.06 after 16 to 20 weeks. These results agreed well with findings by preferential looking or Teller acuity card. Conclusion：VHD was useful in measuring visual acuity in infants up to 6 months after birth.