研究目的：在震波碎石治療中，準確的瞄準結石一直是一個重要的問題。我們已經利用超音波發展出一種即時追蹤系統，使震波碎石機能準確瞄準移動的結石。我們將繼續驗證此系統的準確性。材料與方法：本研究使用我們發展出的超音波即時追蹤系統為基礎，我們使用相符合率測驗來評估此系統的可靠性，這測驗專注於相符合率提升的程度，此程度指出結石落在聚焦壓力區內的程度。我們設定有效聚焦壓力區為在離震波反射器第二焦點的半徑7.5 mm的區域。對每一個結石軌跡的圖像皆施以追蹤及不追蹤的相符合率測驗來驗證此一系統。結果：我們一共收集了13位病人的超音波影像結石軌跡的圖像。相符合率測驗的程度由85.9±8.7%（未追蹤）提高到98.9±1.3%（有追蹤）。統計上二組之間的差異有顯著有意義的差異（成對t檢定，p< 0.01）。結論：由此結果顯示本結石追蹤系統能相當優異地提高追蹤結石情況下的相符合率。亦即是震波碎石機對結石的瞄準被提升。此追蹤系統在持續追蹤瞄準結石的能力是可信的。

OBJECTIVE: during shock wave lithotripsy, accurate targeting on a stone is always a big problem. We have developed an ultrasound-based real-time tracking system for a shock wave lithotriptor to accurately target on a moving stone. We continued to verify its reliability in this study. MATERIALS AND METHODS: The developed ultrasound-based real-time tracking system was used in this study. A coincidence test was established to verify the reliability of the tracking system. The test indicates the degree of matching of the stone within the effective focal area. We designated the effective focal area to be an area with a radius of 7.5mm from the second geometric focus of the shock wave reflector. The 7.5 mm length consists of a 5 mm portion in which the pressure exceeded 100 bars and a 2.5 mm portion for the stone radius. For each stone trajectory, experiments were conducted under tracking and non-tracking conditions. RESULTS: Thirteen ultrasound stone trajectories recorded from patients were collected and used in vitro to test the system. The average value of the coincidence ratio in the non-tracking group was 85.9±8.7%, and was 98.9±1.3% for the tracking group. The difference between non-tracking and tracking groups was statistically significant (paired t-test, p<0.01). CONCLUSIONS: The coincidence ratio was improved by using the ultrasound-based real-time tracking system. That is, targeting of the shock wave lithotriptor was improved. It seems that the tracking system is reliable to continuously target on the stone.