焦点深度拡張型眼内レンズ挿入眼における他覚屈折値と自覚屈折値の差

Differences between autorefraction and subjective refraction after implantation of diffractive extended depth of focus intraocular lenses.

要約　目的：エシェレット回折デザインを用いた焦点深度拡張型（EDOF）多焦点眼内レンズ（IOL）では，1次回折光により遠方焦点が得られる。本IOL挿入眼における，他覚屈折値と自覚屈折値が一致するか前向きに検討した。

対象と方法：対象は，ZXR00V（J & J Vision）を挿入した42例63眼とし，術後3か月の他覚屈折値，矯正遠方視力，自覚屈折値を検討した。他覚屈折値は，オートレフケラトメータ（オートレフ）と波面収差計を用いて測定した。他覚検査における球面度数，円柱度数，等価球面（SE）度数が，自覚検査値と一致するかを評価した。

結果：術後の平均矯正視力は，−0.14±0.05logMAR，自覚屈折値は球面度数−0.03±0.43D，円柱度数−0.42±0.43D，SE度数−0.24±0.65Dであった。他覚の球面，円柱度数において，機器間で差はなかった（p＝0.51，0.79）。オートレフによる他覚屈折値は，球面度数−0.69±0.43D，円柱度数−0.70±0.41D，SE度数−1.04±0.42Dであった。自覚屈折値と有意な差（p＜0.001）がみられ，その値は球面度数−0.65±0.24D，円柱度数−0.28±0.22D，SE度数−0.80±0.22Dだけ近視側にずれていた。

結論：エシェレット回折デザインを用いたEDOF IOL挿入眼の他覚的屈折値はSE度数で約1D近視側になることに留意して，自覚的屈折検査を行うことが必要と考えられた。

Abstract　Purpose：In an extended depth of focus（EDOF）multifocal intraocular lens（IOL）utilizing an echelette grating design, the 1st-order diffraction light constitutes the far focus. Differences between objective and subjective refractions of eyes with this EDOF IOL were evaluated prospectively.

Cases and Methods：EDOF IOL, ZXR00V（J & J Vision）were implanted in 63 eyes of 42 patients. Objective refractions, corrected distance visual acuity, and subjective refractions were examined 3 months postoperatively. Objective refractions were measured using an auto-refractometer and a wavefront analyzer. Differences in spherical, cylindrical and spherical equivalent（SE）refractions of the objective and subjective examinations were evaluated.

Results：The mean postoperative visual acuity was −0.14±0.05 logMAR, and the subjective spherical, cylindrical and SE refractions were −0.03±0.43D, −0.42±0.43D, and −0.24±0.65D, respectively. There were no differences between the two instruments regarding the objective spherical, cylindrical and SE refractions（p＝0.51, 0.79）. The objective refractions with an auto-refractometer were −0.69±0.43D, −0.70±0.41D, and −1.04±0.42D, which were significantly more myopic than those of subjective refractions（p＜0.001）, and the differences were −0.65±0.24D, −0.28±0.22D, and −0.80±0.22D, respectively

Conclusions：After implantation of EDOF IOLs utilizing an echelette grating design, the myopic differences in objective refraction（approximately 1D in SE）should be considered in subjective refraction examinations.