角膜周辺部で測定した場合のTono-PenⅡの信頼性

A ccuracy of Tono-pen Ⅱ when applied to peripheral cornea

　Tono-PenⅡを用い角膜周辺部で測定した眼圧値を，Goldmann眼圧計による測定値と統計学的に比較検討した。対象は正常角膜を有する24例42眼で，Tono-PenⅡによる測定部位は角膜中央部・上方・下方・鼻側・耳側とした。Tono-PenⅡの各部位での測定値の平均値とGoldmann眼圧計の測定値を比較すると，角膜上方での測定値にのみ統計学的に有意差（p＜0.05）が認められた。Goldmann眼圧計の測定値と各部位でのTo-no-PenⅡの測定値との相関係数は，0.88〜0.92とよく相関していた。両者の測定値の読みの差が±2mmHg以内であった割合は，61.9〜83.3％でバラツキも少なく，Tono-PenⅡによる眼圧測定は，角膜周辺部で行っても信頼性が高いと考えられた。

We evaluated the reliability of intraocular pres-sure readings by Tono-pen Ⅱ by Oculab when applied to the peripheral cornea. We obtained pres-sure readings by applying the tip to 5 corneal areas: central, nasal, temporal, upper and lower ones. Measurement was performed in 42 eyes of 24 persons with intraocular pressure ranging from 7 to 26mmHg by applanation. The pressure readings were statistically similar between Tono-pen Ⅱ and applanation except when Tono-pen Ⅱ was applied to the upper cornea, where a higher reading was obtained than by applanation (p＜0.05) . Otherwise, Tono-pen Ⅱ reading from peripheral cornea showed good correlation with applanation ones (r=0.88-0.92) . The readings between Tono-pen Ⅱ and applanation were less than 2mmHg in 61.9%, 78.6%, 83.3% and 69.0% when read at upper, lower, nasal and temporal corneal areas respectively. The findings indicate that Tono-pen Ⅱ is useful when it is applied to peripheral corneal areas.