Abdominal Aortic Dissection

Abdominal Aortic Dissection

Aortic dissection occurs when blood dissects into the media of the aortic wall through an intimal tear. It is generally secondary to hypertension. In young patients with aortic dissection, an underlying process such as Marfan syndrome should be investigated. Dissection originating in the in-frarenal abdominal aorta is very rare and, given the vagueness of presenting symptoms of uncomplicated dissection, diagnosis is very difficult in the early stages. In the absence of a pulsatile abdominal...

Portal Hypertension

Mri Collaterals Portal Hypertension

DSA in patients with portal hypertension is often performed to measure portal venous pressures and the portal-systemic pressure gradient. These measurements can not be made directly using Fig. 2a-c. 44-year-old patient with hepatic cirrhosis and repeated gastrointestinal haemorrhage. Three rotated MIP displays of the portal venous phase 3D data set depict the portal venous morphology to good advantage. The splenic vein is dilated and is draining into a convolute of gastroesophageal collaterals...

Clinical Examples

Causes Subclavian Steal Syndrome

MRI permits an excellent workup of the anatomic and physiologic status particularly as regards congenital cardiovascular malformations of the aorta. Since children or young adults most frequently require evaluation, the lack of ionizing radiation and the excellent safety profile of the applied MR contrast agents are a considerable advantage when compared with other diagnostic modalities. Moreover, since patients with congenital cardiovascular malformations need regular follow-up, it is...

Liver Transplantation

Splenorenal Shunt

Imaging proof of a patent portal vein is required for a patient to be placed on the liver transplant waiting list. Ultrasound can image the portal vein but is not 100 reliable. When ultrasound fails to adequately visualize the portal vein, 3D CE MRA offers a safe, accurate, and comprehensive assessment of portal venous anatomy without requiring iodinated contrast 16,17 . 3D CE MRA also evaluates the splenic vein, superior mesenteric vein SMV , inferior mesenteric vein, IVC and potential varices...

Superior Mesenteric Vein Anatomy

Inferior Mesenteric Vein Anatomy

The mesenteric venous anatomy Fig. 1 parallels the arterial distribution see VI.3 3-4 . The portal vein is formed by the splenic and superior mesen-teric veins. The pancreatic, left gastroepiploic, short gastric, and inferior mesenteric veins and splenic vein branches drain into the main splenic vein. The inferior mesenteric vein receives its supply from the left colic, sigmoid and superior hem-orrhoidal veins. It usually joins the splenic vein prior to the junction of the splenic vein with the...

Inferior Mesenteric Artery

Branches The Middle Colic Artery

The inferior mesenteric artery IMA Fig. 1c arises from the ventral aspect of the aorta approximately at the level of the L3 vertebral body and measures between 1.2 and 5.5 mm in diameter at its origin. This makes it difficult to image consistently with MRA 6 .The first branch of the IMA is typically an ascending branch, which represents the left colic artery. The inferior mesenteric artery then gives off the sigmoid branches. More distally, the IMA becomes the superior rectal artery. Fig. 1a-c....

Imaging of Hemodialysis Access Fistulas

Hemodialysis Shunt

In general early and late complications in hemodialysis shunts have to be distinguished. Typically, early complications relate to surgical problems or atypical draining veins Fig. 11 . Late complications in hemodialysis shunts may occur in the feeding artery, the arterial anastomosis Fig. 12 , the fistula itself, the venous anastomosis and the draining vein Fig. 13 . Arterial complications are relatively infrequent most common problems are due to stenoses at the venous anastomosis, most often...

Clinical Indications Background

Middle Cerebral Artery Internal Carotid

Clinical indications for noninvasive vascular diagnostic modalities have increased in the last ten years due to rapid developments in technology and subsequent improvements of spatial resolution. Improvements in imaging of intracranial vessels have occurred in large part due the possibility to acquire larger volumes. Major advantages of MRA over CTA for the study of intracranial circulation are that it is less invasive, is not entirely dependent on the need for contrast media, and permits...

Normal Anatomy and Anatomic Variations

Vertebral Artery

The aortic arch and great vessel origins are best shown on the CE MRA. They are also seen to relatively good advantage on the 2D TOF images although stairstep artifact is usually quite noticeable in this region due to a combination of vessel pulsation and respiratory motion at the level of the aortic arch. This motion degradation is minimized with CE MRA due to the rapid acquisition and the averaging of pulsatile motion across the entire 3D data acquisition set. The common carotid arteries...

Accuracy of Technique Published in Literature Critical Review of Clinical Applications

Left Femoral Popliteal Bypass

In a preliminary study, 5 healthy volunteers and 6 patients with angiographically documented peripheral vascular disease were examined using Gd-BOPTA at a dose of 0.3 mmol kg bodyweight. Compared with conventional DSA, two independent blinded readers noted overall sensitivities of 91 95 CI 0.76-0.98 and 94 0.8-0.99 , and specificities of 93 0.85-0.97 and 90 0.820.96 , for the detection of substantial vascular disease luminal narrowing gt 50 15 . Furthermore, inter-observer agreement for the...