ERGの各波面積計測法（第1報）—律動様小波消失型糖尿病性網膜症のa波面積値

Method of Measurement on the Area of the Each Wave of ERG.Report I:The Area of A-wave-glen of the Lacked Oscillatory Potential Type of Diabetic Retinopathy

緒言

　糖尿病性網膜症（以下本症と略す）のERGが特異な変化をきたすことは既に知られている^4）6）7）。著者^5）は，先に本症21例の律動様小波を検索し，減弱もしくは消失傾向にあることを確かめ，特に各小波群の頂点潜時を比較検討した結果，頂点潜時にやや短縮傾向のみられることを知り得た。今回はa波の面積を計測方法について述べ，本症で律動様小波が全く消失した5例10眼を対象に，a波振幅，a波頂点潜時ならびにa波の谷の面積を計測し，結果を得たので報告する。

The method of measurement on the area of a-wave-glen of ERG was designed. The area was calculated with the amplitude of a-wave and tentatively named "bridge time" which is the length of time between the point of stimu-lation and the point crossing the straight line drawn parallel to the baseline.

The area of a-wave-glen

=amplitude of a-wave×bridge time/2

(square msec. mV)

The area of a-wave-glen of ERG of the five patients of diabetic retinopathy lacking the oscillatory potential was measured by the above method.

The area showed the slight decrease accord-ing to the degree of the diabetic retinopathy.