The Comparison of Glomerular Filteration Rate by Kidney Depth in Dynamic kidney Scan

동적신장검사에서 신장깊이에 따른 사구체여과율 비교

Purpose Find out about the significance of the GFR values calculated by the kidney depth is measured by comparing the values obtained for kidney depth was measured GFR in the CT image kidney depth and is calculated by Tonnesen law in $^{99m}Tc$-DTPA dynamic kidney scan with each applies. Materials and Methods Among patients with normal value (75~120 mL/min) computed GFR conducted of dynamic renal scan to visit from February 2013 to February 2014 and donor GFR values in patients with normal value. The mean age was 46.9 years with 14 men 13 females. We used abdomen CT image which checked before conducting dynamic Kidney scan for measuring the depth of kidney. We only used CT image that contains renal hilum and measured outermost front of the kidney from the skin surface (a) and the final surface (b) caculated the average depth of [(a + b) / 2] respectively. Using the same ROI in order to limit the change in GFR values by the other additional element was set before and after the depth value was excluded from the GFR falls kidney disease. Results Using Tonnesen law the average value was caculated 5.94 cm from the right kidney 5.90 cm from the left kidney. It was 6.83 cm, 8.71 cm in the left kidney and the right kidney average value of the depth measured on the basis of the CT image. The respective increase in left kidney 0.93 cm and right kidney 2.77 cm calculated on the basis of CT image actually measured values. GFR was calculated as the average depth of the subject calculated by the method Tonnesen $83.3{\pm}9.79mL/min$. $98.6{\pm}14.07mL/min$ GFR was applied to calculate the average depth of the subjects using the CT image, is the difference appears 15.26 mL/min was increased after seting up depth value, P value was less than 0.01 which is significant. Conclusion The difference between GFR before-after setting up depth value cause that the different of depth value. Is a measured depth of the extension value of the calculated estimates Whereas Tonnesen kidney depth method is to use in calculating the value of GFR in a typical dynamic elongation test depth derived using the CT image depth. Is thought to be able to calculate more accurately the GFR value by the distance to the center of kidney more accurately measured in the skin thereby.

서론: 신장기능을 평가하는데 중요한 지표가 될 수 있는 GFR을 측정하는 데에는 여러 가지 검사방법이 있다. 핵의학 검사에서 사용하는 동적신장검사는 Gates법을 바탕으로 GFR을 구한다. 본 저자는 동적신장검사에서 일반적으로 GFR을 측정하는데 사용되는 Gates법에 신장깊이를 측정하는 방법을 달리하여 각각 적용하여 보았다. Tonnesen방정식을 이용한 신장깊이와 CT사진에서 도출한 신장깊이를 측정한 후, 두 가지 측정방법에 따른 신장깊이와 GFR의 차이를 비교분석하고 그 유용성을 평가하고자 한다. 실험장비및 재료: Dual Detector인 GE사의 감마카메라에 Low energy collimator를 장착하여 사용하였으며 실험에서 대상자에게 투여하는 방사성 의약품은 $^{99m}Tc$-DTPA이다. 실험대상 및 방법: 2013년 2월에서 2014년 2월까지 1년간 본원에서 동적신장검사를 시행한 환자 중 양쪽신장의 GFR이 정상인 27명을 대상으로 하였다. 각 대상자들의 신장깊이를 Tonnesen방정식과 CT사진을 토대로 각각 산출하고 Gates법에 대입하여 GFR을 구하고 비교분석하였다. 결과: 신장깊이는 좌신에서 0.93 cm 우신에서 2.77 cm 차이가 났으며 CT사진으로 구한 깊이수치가 더 큰 것으로 나왔고 GFR 값 역시 15.1 mL/min 상승하였다. 고찰 및 결론: 한국인의 신장깊이가 서양인과 다르며 깊이를 측정하는 방법에 따라 GFR이 변할 수 있으므로 신장깊이 측정에 있어 신뢰도를 높일 수 있는 방법들에 대한 연구가 계속되어야 한다.