Bressler E L, Rubin J M, McCracken S
Radiology. 1987 Aug;164(2):343-6. doi: 10.1148/radiology.164.2.3299485.
Tubular structures proximal to the right and left hepatic ducts, when seen with ultrasonography, are generally considered to be abnormally dilated ducts. However, newer, electronically focused transducers reveal peripheral tubular structures paralleling portal venous branches. The diameters of all visible tubular structures that would have been thought to be bile ducts were measured in 50 persons with no evidence of hepatobiliary disease. "Ducts" were seen with the following frequencies: right hepatic, 100%; right anterior, 100%; right posterior, 88%; left hepatic, 98%; left medial, 62%; left lateral, 96%; left lateral superior, 54%; and left lateral inferior, 54%. All ducts proximal to the right and left hepatic ducts were 2 mm or less in diameter. Those proximal to the common hepatic ducts averaged approximately 20% of the diameters of their accompanying portal veins. Except for 4% of the left lateral inferior ducts, no ducts proximal to the common hepatic ducts were more than 40% the diameter of their respective portal vein branches. Mere observation of parallel channels proximal to the right and left hepatic ducts is therefore not evidence of biliary dilatation.
超声检查时，左右肝管近端的管状结构通常被认为是异常扩张的胆管。然而，新型电子聚焦换能器显示出与门静脉分支平行的周边管状结构。在50名无肝胆疾病证据的人中，测量了所有被认为是胆管的可见管状结构的直径。“胆管”出现的频率如下：右肝管，100%；右前叶胆管，100%；右后叶胆管，88%；左肝管，98%；左内侧叶胆管，62%；左外侧叶胆管，96%；左外侧叶上段胆管，54%；左外侧叶下段胆管，54%。左右肝管近端的所有胆管直径均在2mm或以下。肝总管近端的胆管平均约为其伴行门静脉直径的20%。除4%的左外侧叶下段胆管外，肝总管近端的胆管直径均不超过其各自门静脉分支直径的40%。因此，仅仅观察左右肝管近端的平行通道并非胆管扩张的证据。
