轉斜眼球運動是利用眼睛周圍的內直肌與外直肌使眼睛同時向內(convergence)或向外(divergence)轉動，使我們可以感知事物的距離，讓我們所看的，成為有立體的景色。視覺功能障礙會影響我們個人日常正常生活和眼球轉斜運動；例如：複視、眼球內聚能力不足還有斜視。
有些視覺功能障礙可藉由眼鏡或隱形眼鏡改善，而有些可以經由臨床上的治療整治，這種臨床上的治療稱為視覺治療或視覺訓練。視覺治療是對於我們大腦與眼睛的一種物理治療方式，在臨床上它用來改善病人的症狀，減少隱斜視的程度，增加眼球聚焦的範圍，以及恢復眼球內聚的能力。但是並沒有太多的研究在探討視覺治療對我們人類的視覺系統產生影響。
我們的研究目的是發展一套轉斜眼球運動量測系統，利用這套系統對於患有外斜視的病人設計一套視覺治療的流程。並且觀察患有外斜視的病人在視覺治療前後的眼球動態改變。在經過八週視覺訓練後，結果顯示病患的向內眼球轉斜運動以及向外眼球轉斜運動的動態反應變的比較好。除了眼球轉動的動態更穩定外，眼球追跡物體轉動的速度也變的比較快，在未來分析各種視覺功能障礙病患在視覺治療前後的動態改變，將可以幫助我們了解視覺治療對於視覺系統所產生的影響以及其相關生理機制。

Vergence eye movements used the medial and lateral recti muscles to rotate the eyes. Vergence oculomotor movements are the inward (convergence) and outward (divergence) turning of the eyes allowing depth perception. Vision dysfunctions such as amblyopia, convergence insufficiency and strabismus affect a person’s daily living activities and some of them affect vergence eye movement. Some visual dysfunctions can be improved with glasses or contact lens, while others can be remediated through taking clinical treatment, which is called vision therapy or vision training. Vision therapy is a type of physical therapy for the eyes and brain. In clinical treatment, it is used to improve patient’s symptoms resulting in a reduced phoria level, increased fusional ranges and reduced near point of convergence. However there are not such researches studying about how vision therapy affects on human visual system.
The purpose of this research is to develop a vergence eye movement measurement system and observe the difference of eye movement dynamic before and after vision training in patients with exotropia. We use this system to design a vision training protocol for a subject with exotropia. The result shows that both convergence and divergence responses become better after 8 weeks vision training. Not only the dynamic of responses is more stable, but the velocity becomes faster.
In the future, quantifying eye movement on subjects with different vision dysfunction before and after vision training is needed. This will be helpful in understanding how vision training causes the improvement to eye movement system.

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