간담도스캔의 영상수집방법에 따른 담즙배출율의 비교분석

A Comparative Analysis of GBEF According to Image Aquisition Method in Hepatobiliary Scan

Purpose The quantitative analysis of gallbladder emptying is very important in diagnosis of motility disorder of gallbladder and in biliary physiology. The GBEF obtain the statics aquisition method or the dynamic acquisition method in two ways. The purpose of this study is to compare the GBEF value of statics acquisition method and the dynamic acquisition method. And we find the best way for calculate GBEF. Materials and Methods The quantitative hepatobiliary scan with ⁹⁹ᵐTc-mebrofenin was performed of 27 patients. Initial images were acquired statically, for 60 min after injection of the radioactive tracer. And if the gallbladder is visualized to 60 min, performed stimulation of gallbladder (1egg, 200 mL milk). After that, started acquisition of dynamic image for 30 min. After that, image of after fatty meal of the statics method were acquired on equal terms with 60 min image. The statics GBEF was calculated using the images of before fatty meal and post fatty meal by the statics method. The dynamic GBEF was calculated using the images of time of maximum bile juice uptake (Tₘₐₓ) and time of minimum bile juice uptake (Tmin) images from the gallbladder time-activity curve. A bile juice is secreted from gallbladder while eating a fatty meal. that is named early GBEF and that was calculated using before fatty meal image of the statics method and 1 min image of the dynamic method. Results The result saw very big difference between two according to Tₘₐₓ. The result, were as follows. 1) In case of less than 1 min, the dynamic mean GBEF was 40.1±21.7%, the statics mean GBEF was 51.5±23.6% in 16 cases. The early mean GBEF was 14.0±29.1%. The GBEF of statics method was higher because that include secreted bile juice while performed stimulation of gallbladder. A difference of GB counts according to acquisition method and the early bile juice counts was 17.6±14.8% and 13.5±15.3%. 2) In case of exceed than 1 min, the dynamic mean GBEF was 31.0±19.7%, the statics mean GBEF was 21.3±19.4% in 7 cases. The early GBEF was – 6.9±4.9%. The GBEF of dynamic method was higher because that include concentrated bile juice to Tₘₐₓ. A difference of GB counts according to acquisition method and the early bile juice counts was 14.3±7.3% and 5.9±3.9%. Conclusion The statics method is very easy and simple, but in case of Tₘₐₓ delay, the GBEF can be lower. The dynamic method is able to calculate accurately in case of Tₘₐₓ delay, but in case of Tₘₐₓ is less than 1 min, the GBEF can be lower because dynamic GBEF exclude secreted bile juice while performed stimulation of gallbladder. The best way to calculate GBEF is to scan with dynamic method preferentially and to choose suitable method between the two way after conform Tₘₐₓ on the T-A curve of the dynamic method.