研究背景與目的
在從事經皮腎造廔取石術之前的穿刺定位時，經常遭遇如何定位後腎盞結石或後腎盞的困難，造成手術時間的增長和手術失敗，因此欲藉由C臂電腦斷層來輔助手術定位。本篇回溯性研究的主要目的，乃藉由分析影像資料，來探討比較C臂電腦斷層輔助定位是否比傳統定位更能縮短手術時間、降低出血的危險性與提高手術成功率。
研究方法
自 2008年1月至2009年6月，從影像資料庫找出共有54個複雜或較大的腎結石病患（男=39，女=15），平均齡 54.2±11.5歲，他們經由泌尿科醫師轉介至本科先做經皮腎造廔取石術前的穿刺定位。病人分成兩組，第一組為傳統影像組，有28人接受28次經皮取腎結石術前的穿刺定位手術，在穿刺前只用傳統的靜脈注射泌尿道攝影或腹部攝影來評估穿刺目標與路徑；第二組為C臂電腦斷層組，有26人接受28次經皮取腎結石術前的穿刺定位手術，除了使用傳統的靜脈注射泌尿道攝影或腹部攝影外，還多加上C臂電腦斷層影像來輔助評估穿刺路徑，最佳的後腎盞結石或腎盞穿刺目標與路徑將被決定。我們比較兩組的穿刺手術時間、是否明顯的顯影劑滲漏、是否明顯出血、穿刺手術成功率與經皮取腎結石術後的剩餘腎結石。
結果
〈1〉第一組無C臂電腦斷層輔助組的穿刺手術時間為37.0±11.6分，第二組有C臂電腦斷層輔助組的穿刺手術時間為26.5±8.8分，兩組在手術穿刺時間上達明顯差異（p<0.001）。〈2〉第一組穿刺手術失敗的有2次，成功率為92.9%；第二組穿刺手術全部成功〈100%〉（p=0.15）。〈3〉第一組穿刺手術失敗的2人次，在下一次藉由C臂電腦斷層輔助後全部手術成功。〈4〉第一組顯影劑滲漏有10次(35.7%)，第二組則有4次(14.2%) （p=0.064)。〈5〉第一組明顯出血有6次(21.4%)，第二組則有4次(14.2%) （p=0.485）。〈6〉第一組術後追蹤剩餘腎結石有14次(50%)，第二組則有12次(42.9%)（p=0.592）。〈7〉研究變項中，除手術穿刺時間達顯著差異外，其餘的的變項皆無統計上顯著差異。
結論
在經皮腎造廔取石術前的穿刺定位時，若有C臂電腦斷層來輔助評估並決定最佳的後腎盞結石或後腎盞穿刺目標與路徑，手術時間將可明顯減少，同時也減少醫師使用放射線透視的時間與所接受的放射劑量。
Background and Purpose
When performing the puncture before the percutaneous nephrolithotomy (PCNL), we usually faced the difficulty of how to localize the posterior calyceal stone or calyx which caused longer procedure time and failure. The aim of this study is to examine whether the use of C-arm computed tomography (CT) during percutaneous nephrolithotomy (PCNL) decreases the procedure time, the risk of bleeding and increases the technical success rate.
Materials and Methods
Between March 2008 and June 2009, we retrospectively reviewed the data base of radiology to find out 54 patients with complex or big renal stone. There were 39 men and 15 females with mean age of 54.2±11.5 years old. They were referred to our department to perform the puncture before percutaneous nephrolithotomy. Before puncture, the group 1(n=28 with 28 punctures) used only the IVU film or KUB as initial evaluation of the access. The group 2 (n=26 with 28 punctures) used the IVU film and multiplanar C-arm CT images
reconstructed from data acquired during C-arm rotation. The desired posterior calyceal stone or calyx to be punctured will be decided. We compared the procedure time, contrast extravasation, significant bleeding, success rate, and residual stone after PCNL.
RESULTS
The mean procedure time was significantly reduced in group 2 compared with that of the group 1 (26.5±8.8 min vs 37.0±11.6 min, P<0.001). Two of 22 patients in the group 1 failed with success rate of 92.9%. The group 2 had 100% success rate（p=0.15）.Among the group 2, there were two patients were initially difficult to approach due to relatively radiolucent stone. But the stones were well seen in the 3D and MPR image of C-arm CT. All 26 patients in group 2 had good 3D and MPR image, which were easy to decide the posterior calyceal stone as puncture target. The group 2 had lower rate of contrast extravasation (14.2% vs 35.7%, p=0.064), significant bleeding (14.2% vs 21.4%, p=0.485) and residual stone (42.9% vs 50%, p=0.592) than the group 1 but without statistic significance.
CONCLUSION
C-arm CT guidance could decrease the puncture time in percutaneous nephrolithomy.
