- 期刊
- OpenAccess
Main Portal Vein Thrombosis: Its CT Patterns and Related Etiology
主門靜脈栓塞：CT影像及其導因
摘要
主門靜脈栓塞為一併發症通常是因肝硬化，炎症，血液遲滯，惡性腫瘤或其他因素等等所致。以前文獻尚未有就主門靜脈栓塞之電腦斷層攝影 (CT) 之影像與其關聯原因提出過有系統的分析及結論。在我們系列中共有220主門靜脈栓塞病例接受注射顯影劑及其後之CT影像作為分析。我們發現共有5種類型主門靜脈栓塞之CT影像。主門靜脈栓塞來自惡性腫瘤是以決堤型 (breach type) 與飄浮型 (floating type) 各為83.1%與16.9%，門靜脈亦較為粗大 (79%)，在判讀CT時不易被忽略。若追蹤其決堤口處，尚可把不明顯之腫瘤發現出來。壁上型 (mural thrombus) 是門靜脈高壓之特有型別 (69.8%)，其成因與CT影像約與高血壓所致的動脈粥樣硬化之栓塞 (plug) 相仿，飄浮型、環型 (ring type) 及閉鎖型 (obliteration type) 為非特異之主門靜脈栓塞，但是炎症導因而致靜脈發炎會使門靜脈壁之顯影更為強烈，故在環型主門靜脈栓塞出現極明顯之輪框顯影現像 (rim enhancement) 。閉鎖型多為血塊栓塞之後期現象，它通常存在於其導因不會引起太多的臨床徵象與症狀者，例如血流遲滯等原因。熟悉各類型主門靜脈栓塞之CT發現，可以增加我們診斷之能力及藉此找出其導因。
並列摘要
Thromosis of the main portal vein (MPVT) is usually a complication of preexisting conditions such as malignant tumors, liver cirrhosis, infection, or stasis blood flow, or else it is idiopathic. No conclusive evidence of CT findings of MPVT in relation to etiology could be found in the literature. In fact, different mechanisms may cause different types of MPVT. Two hundred and twenty patients with MPVT who received CT scans without and with contrast in our series were analyzed with respect to the relationship of the CT pattern to the MPVT and its etiology. We identified five types of MPVT patterns in the CT scans. Malignancy with intravascular invasion may be present as breach type (83.1%) and floating type (16.9%) of MPVT, and the size of the portal vein is usually larger than 2 cm (79%), which is evident in CT scans and is less subject to misinterpretation. Tracing the break area of the portal wall can help in finding a subtle tumor. Mural thrombus is specific to portal hypertension (69.8%); the picture and mechanism may be similar to an atherosclerotic plug in systemic hypertension. The floating, ring, and obliteration types may not be specifically related to etiology; however, rim enhancement of a vasa vasorum may intensify in infective conditions. The obliteration type is probably the late phase of a blood clot thrombus in MPVT; it is seen in cases with silent clinical symptoms and signs in the period of MPVT formation, such as in stasis blood flow. Familiarity with image patterns may improve the diagnosis of an MPVT and discovery of its related etiology.