Usefulness of Digital Subtraction Technique in the Contrast-enhanced Multi-phasic Abdominal MR angiography.
10.3348/jkrs.2001.45.2.175
- Author:
Hui Joong LEE
1
;
Hun Kyu RYEOM
;
Jae Hyun KWON
;
Sang Kwon LEE
;
Yong Min JANG
;
Yong Sun KIM
;
Yong Joo KIM
;
Duck Sik KANG
Author Information
1. Department of Diagnostic Radiology, School of Medicine, Kyungpook National University, Kyungpook National University Hospital.
- Publication Type:Original Article
- Keywords:
Magnetic resonance(MR), angiography;
Digital subtraction angiography;
Abdomen, MR
- MeSH:
Angiography*;
Angiography, Digital Subtraction;
Humans;
Hypertension, Portal;
Magnetic Resonance Angiography;
Masks;
Mesenteric Artery, Superior;
Portal Vein;
Subtraction Technique*;
Veins
- From:Journal of the Korean Radiological Society
2001;45(2):175-182
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: To assess the usefulness of digital subtraction contrast-enhanced multi-phase magnetic resonance angiography (MRA) for evaluation of the vessels of the gastrointestinal system. MATERIALS AND METHODS: Twenty-five patients who underwent abdominal MRA for evaluation of the vessels of the gastrointestinal system were included in this study. MRA was performed using a 1.5-T scanner and the 3-D turbo-FLASH sequence. Subtraction images of the arterial and portal venous phases were obtained by subtracting arterial phase images from mask images and portal venous phase images from arterial phase images, respectively. Each set of images was processed using a maximum-intensity projection (MIP) algorithm to produce three-dimensional angiograms. We compared overall image quality and the visibility of normal and abnormal vessels between subtraction and non-subtraction MRA. RESULTS: In terms of subjective image quality, subtraction and non-subtraction MRA was similar both the arterial and portal venous phases (p>0.05). During the arterial phase, subtraction MRA visualized more peripheral branches of the left gastric and superior mesenteric arteries than non-subtraction MRA (p<0.05), and during the portal venous phase, subtraction MRA demonstrated more peripheral branches of the superior mesenteric (p<0.01), splenic (p<0.05) and left portal vein (p<0.05) than non-subtraction MRA. In addition, overall visibility of the arterial and portal venous branches was superior with subtraction MRAs than with non-subtraction MRA. Both of these detected all anomalous arterial branching (n=5) and abnormal (encased or obstructed) portal veins (n=5). Subtraction MRA visualized 17 portal venous collaterals in six patients, whereas non-subtraction MRA visualized only seven collateral veins. CONCLUSION: In contrast-enhanced abdominal MRA, the digital subtraction technique permits visualization of more distal branches of the vessels of both the arterial and portal venous systems without significant degradation of image quality. The technique is particularly useful for the detection of portal venous collaterals in patients with portal hypertension.
