Gräf M, Becker R, Neff A, Kaufmann H
Universitäts-Augenklinik für Schielbehandlung und Neuroophthalmologie, Giessen.
Ophthalmologe. 1996 Aug;93(4):333-40.
Recently, a new preferential looking (PL) test has been presented for measuring visual acuity in infants and young children (Cardiff Acuity Test, CAT). The PL target is a schematic vanishing picture composed of isoluminant lines with different spatial orientations. Fifty-three healthy children (4-34 months, group 1), 28 (4-35 months) children at risk for amblyopia due to strabismus (group 2), 19 healthy subjects, and 157 patients (group 3) were tested with the CAT. In group 2 the CAT was compared with the fixation preference test. In group 3 the CAT was compared with a recognition test (Landolt C test). In group 1 the interocular difference of the CAT data was a maximum of 1 dB (70% 0 dB, 30% 1 dB, 1/3 so-called octave). Thus, an interocular difference of > 1 dB was considered to be suggestive of monocular or asymmetrical visual impairment. The maximum value 6/6 was frequently achieved (RE 44%, LE 36%, > 18 months RE 57%, LE 46%). In group 2 only 20% of the monolateral strabismic children showed an interocular difference > 1 dB in the CAT. In group 3 we found significant correlations between the CAT and Landolt acuity. A ratio of about 1.7/1 between CAT and Landolt acuity remained constant in cataract eyes as compared to healthy eyes. In amblyopic eyes due to strabismus this ratio was 3.7/1. Thus, amblyopia was underestimated with the CAT. Without limiting the examination distance, interocular differences > 1 dB in the CAT occurred in 52% of the strabismic amblyopic patients (potential sensitivity). At a distance of 1 m this rate decreased to 22% (real sensitivity). In conclusion, the CAT definitely lacks sensitivity for strabismic amblyopia. The data suggest that the real sensitivity could be improved by using higher spatial frequencies. The use of familiar shapes instead of gratings such as PL targets affects cooperation favorably in 12- to 36-month-old children.
最近，一种用于测量婴幼儿视力的新型优先注视（PL）测试（加的夫视力测试，CAT）已被提出。PL目标是一幅由具有不同空间方向的等亮度线条组成的示意性消失图片。对53名健康儿童（4 - 34个月，第1组）、28名因斜视有弱视风险的儿童（4 - 35个月，第2组）、19名健康受试者以及157名患者（第3组）进行了CAT测试。在第2组中，将CAT与注视偏好测试进行了比较。在第3组中，将CAT与识别测试（Landolt C测试）进行了比较。在第1组中，CAT数据的眼间差异最大为1 dB（70%为0 dB，30%为1 dB，即1/3所谓的倍频程）。因此，眼间差异>1 dB被认为提示单眼或不对称视力损害。经常能达到最大值6/6（右眼44%，左眼36%，>18个月时右眼57%，左眼46%）。在第2组中，仅20%的单侧斜视儿童在CAT中显示眼间差异>1 dB。在第3组中，我们发现CAT与Landolt视力之间存在显著相关性。与健康眼睛相比，白内障眼中CAT与Landolt视力的比值约为1.7/1，保持恒定。在因斜视导致的弱视眼中，该比值为3.7/1。因此，CAT低估了弱视情况。在不限制检查距离的情况下，52%的斜视性弱视患者在CAT中出现眼间差异>1 dB（潜在敏感性）。在1米的距离时，该比率降至22%（实际敏感性）。总之，CAT对斜视性弱视肯定缺乏敏感性。数据表明，通过使用更高的空间频率可以提高实际敏感性。使用熟悉的形状而非像PL目标那样的光栅，对12至36个月大的儿童的配合有积极影响。
