Classification of hepatobiliary scintigraphy patterns in segmented gallbladder according to anatomical discordance

Figure 3 Typical images of computed tomography and hepatobiliary scintigraphy according to pattern in the normal and segmented gallbladder. A: Hepatobiliary scintigraphy (HBS) in non-segmented gallbladder (GB). Reported GB ejection fraction (GBEF) was 74%; B: Type 1, normal filling and emptying pattern on HBS. Reported GBEF (95%) was reflected in both segments; C: Type 2, emptying defect of the distal segment on HBS. After 60 min, the proximal segment showed normal emptying, but the distal segment showed poor emptying. Reported GBEF (87%) reflects proximal segmentation more than distal segmentation; D: Type 3, filling defect of the distal segment on HBS. As the distal segment is not observed in the scanned image, other radiological validation is required. Reported GBEF (89%) reflects only proximal segmentation. The green line is a rough representation of the outline of the gallbladder per computed tomography. GB: gallbladder; P: Proximal segment (orange arrows); D: Distal segment (black arrows).