Normal vessels are not seen to extend to the pleural surface . The centrilobular bronchiole is not normally visible .

正常的小血管延伸向胸膜下，但是小支气管常无法显示。

In occasional cases , the air-filled centrilobular bronchiole can be recognized as a rounded lucency within a centrilobular nodule .

有时候在小叶中心结节中可见充气支气管呈小圆形透亮区。