雙眼視覺之斜位測量方法差異性研究

目的：比較臨床上以不同測量斜位方法檢測雙眼視覺異常，是否具有差異性及不同環境的適用性。方法：距離6公尺以VG及MR方法測量遠方垂直、水平斜位。距離0.4公尺以VG、MR、MT方法測量近方垂直及水平斜位，並作遠方及近方以不同方法測量結果之比較。結果：以VG及MR兩種測量方法來測量遠方垂直或水平斜位，水平斜位檢定T值為0.43，顯著性0.67，垂直斜位檢定T值為1.04，顯著性0.30，兩者P值均大於0.05無統計上差異。以VG、MR、MT三種方法測得近方垂直及水平斜位，結果垂直斜位F值為0.22，P直為0.80(P>0.05)，三種方法測量近方垂直斜位無統計上差異。水平斜位測量結果變異數分析組間效果F值為0.74，P值為0.48(P>0.05)，三種方法測量近方水平斜位無統計上差異性。結論：由於VG於測量上需要受試者保持隨時注視視標的清晰，必需要有熟練的技巧及提供受試者較佳的引導。研究結果顯示，VG、MR、MT三種方法於近方水平斜位測量並無統計上之差異，因此支持於自由空間的環境下，MT及MR對於測量近方水平斜位有較佳的便利性。同樣的，以VG及MR兩種測量方法來測量遠方垂直或水平斜位，因為沒有顯著差異，於自由空間的環境下，MR是可以考慮的選擇。
Purpose: To perform a differential analysis among clinical measurement methodologies for heterophoria and their applications under various environments. Methods: Von Graefe Technique (VG) and Maddox Rod (MR) were used to measure vertical and horizontal heterophoria at a 6-meter far sight. Von Graefe Technique (VG), Maddox Rod (MR) and Modified Thorington (MT) were used to measure vertical and horizontal at a 0.4-meter near sight. We differentially analyzed the far sight and near sight results. Results: T-test values in the far sight horizontal and vertical phorias for VG and MR methods were 0.43 (p=0.67) and 1.04 (p=0.30) respectively. Since the P values for both horizontal and vertical heterophoria measurements were larger than 0.05, no significant difference was found between VG and MR for far sight heterophoria measurements. Using ANOVA to compare VG, MG, and MT results, near sight vertical phorias and the near sight horizontal phorias had F values 0.22 (p=0.80) and 0.74 (p=0.48). The P values for both horizontal and vertical heterophoria measurements were also larger than 0.05. Thus, there was no significant difference among VG, MR, and MT methods for near sight heterophoria measurements. Conclusion: Because VG method requires persistent focus on a clear target as well as many more skills and better instruction to the patients. The MT and MR methods are more convenient than VG method and convey better reproducibility when the measurements are performed in a free space. Since there was no significant difference between the VG and MR methods for far sight heterophoria measurement and none among VG, MR and MT methods for near sight heterophorias, the MR method can be considered for measurements in a free space environment.