Evaluation of vascular system using MR angiography after liver transplantation: Analysis of 11 cases
- VernacularTitle:磁共振血管成像评价肝移植术后血管形态:11例分析
- Author:
You GUO
;
Xuelin ZHANG
;
Zhao CHEN
- Publication Type:Journal Article
- From:
Chinese Journal of Tissue Engineering Research
2007;11(21):4236-4239
- CountryChina
- Language:Chinese
-
Abstract:
BACKGROUND: Sonography is believed by many scholars to be sensitive for the detection of hepatic arterial thrombosis and stenosis, but it is difficult to show the anastomotic vascular stenosis. MR angiography is better than sonography in the display of vascular anatomy and the diagnosis of various vascular complications after liver transplantation.OBJECTIVE: To evaluate the role of MR angiography (MRA) in the display of vascular anatomy and the diagnosis of various vascular complications after liver transplantation.DESIGN: Contrast trial observation.SETTING: Medical Imaging Center of Nanfang Hospital, Southern Medical University.PARTICIPANTS: Eleven adult male patients had undergone liver transplantations at Nanfang Hospital of Southern Medical University between January 2004 and December 2006. They ranged in age from 40 to 58 years, average 49 yeas. Original causes of liver failure in the study group included cirrhosis (n =9) and primal hepatic carcinoma (n =2) diagnosed by pathohistological methods. And 9 cases had undergone orthotopic liver transplantations while 2 cases with piggy-back liver transplantation.METHODS: Eleven consecutive adult patients underwent MR imaging examinations after orthotopic liver transplantation using a breath-hold 2D True Fast Imaging with Stead-state Precession and Fast Low Angle Shot. MR triphasic contrast-enhanced 3D imaging was also performed. Enhancement scan: A final gadolinium-enhanced axial and coronal T1WI spin-echo sequence with spectral fat saturation was performed after completion of the MRA. The vascular diameter stenosis was calculated according to S (S=[(D-d)/D]×100%) by ECST method, d as the inner diameter of the most obvious stenosis while D as normal diameter. Degree of stenosis: normal as S 0-30%, mild stenosis as S 31%-50%, moderate stenosis as S 51%-85%, and severe stenosis as S 86%-100%. Then the imaging findings after liver transplantation were analyzed. Meanwhile the sonography was performed.MAIN OUTCOME MEASURES: ① MR Image analysis of vascular anatomy and vascular complications after liver transplantation.②Normal findings after liver transplantation by using sonography.RESULTS: All 11 patients were involved in the result analysis.①MRA: The anastomosis of hepatic artery, portal vein and inferior vena cava were smooth in 3 cases. The high signal intensity was seen around portal vein at T2WI in 1 case with a shorter interval after transplantation and persisted 3 weeks. In 1 case, the caliber of the donor portion was smaller than the recipient portion. Among other 8 cases, hepatic artery complication included hepatic artery winding in 2 cases and aneurysm formation of donor's hepatic artery in 2 cases, but the twig of the hepatic artery was normal. Mild Portal vein stenosis at the anastomosis was found in 2 cases, caused by the different calibers of the donor portion from the recipient portion, but the inter-hepatic branches of the portal vein were normal. Clubbed dilatation of hepatic veins end-brush was depicted in 2 cases whose inferior vena cava at the anastomosis was not stenosis. Inferior vena cava thrombosis was found in 1 case. The thrombus displayed the low signal intensity in the high signal intensity of inferior vena cava. By follow-up examination, the degree of clubbed dilatation of hepatic veins end-brush reduced after half a year and inferior vena cava thrombosis disappeared by treatment. ②Sonography: By ultrasound examination, 1 case who had hepatic artery winding combining to aneurysm formation of donor's hepatic artery was discovered just hepatic artery winding. In 2cases that had mild portal vein stenosis at the anastomosis, 1 case was diagnosed normal while the other was not affirmed. The clubbed dilatation of hepatic veins end-brush was not depicted. The others were same as MRI diagnosis.CONCLUSION: Dynamic enhanced 3D MRA imaging can provide a comprehensive assessment of vascular anatomy in most recipients of liver transplants, and is an accurate and quick method to diagnose the vascular complication after liver transplantation.
