Abdominal Vasculature

SONO 131 – Lecture #4

Vascular Anatomy

Arterioles

Artery

Heart

Capillaries Venules

Vein

Vascular Anatomy

Vessel Walls– Tunica intima– Tunica media– Tunica adventitia– Vasa vasorum

Arteries Veins

Circulatory Anatomy

Aorta– Ascending– Arch– Descending– Thoracic– Abdominal

Anterior Branches Abdominal Aorta

Celiac Trunk [Axis]– Common hepatic

Hepatic– Right and Left Hepatic

Gastroduodenal– Left Gastric– Splenic

Left gastroepiploic Short gastric artery Several smaller splenic arteries Great pancreatic artery

Hepatic– Left and right hepatic

SMA– Inferior pancreatic– Duodenal– Colic– Ileocolic– intestinal

IMA– Left colic– Sigmoid– Superior rectal

Celiac Trunk

Mesenteric Arteries

Lateral & Dorsal Branches

Lateral– Phrenic

Paired arteries

– Renal Right & Left

– Gonadal

Dorsal– Lumbar

4 on each side of aorta

Renal Arteries

Sonographic Appearance - Arteries

Sonographic Appearance - Arteries

Sonographic Appearance - Arteries

Abdominal Artery Summary

Abdominal aorta– Celiac Axis

Splenic artery Hepatic artery Left gastric artery

– SMA Inferior pancreatioduatenal Branches to the colon

– Renal Arteries Level L1 – 2

– IMA– Aortic bifurcation

Right & Left Common Iliac arteries

Abdominal Venous System

Inferior Vena Cava

IVC = union of common iliac veins

Tributaries to IVC– 3 anterior hepatic veins– 3 lateral

Right suprarenal veins Renal veins Right testicular or ovarian vein

– 5 lateral abdominal wall veins inferior phrenic + lumbar

– 3 veins of origin common iliac + median sacral

Drains – Abdominal organs – Abdominal structures– Lower extremities

Lateral Abdominal Veins

Suprarenal Veins– Right & Left

Renal Veins– Right & Left

Gonadal Veins– Testicular or Ovarian

Anterior Abdominal Veins

Hepatic Veins– Right– Middle– Left

Portal Venous System

Portal Vein

Splenic Vein

Superior Mesenteric Vein

Inferior Mesenteric Vein

Sonographic Appearance - Veins

Abdominal Vein - Summary

IVC– Right and left

common iliac veins– Renal veins– Hepatic veins

Portal vein– Splenic & SMV– Right & left portal vein– Porta hepatis– Hepatopetal flow

Clinical Indications Abdominal Vasculature Imaging

Arterial– Suspect aortic aneurysm– Possible ateriovenous fistula– Possible mesenteric ischemia

Venous– Leg swelling– Portal hypertension

Arterial Abnormalities

Atherosclerosis - altering of intimal lining of artery by focal accumulation of lipids, complex carbohydrates, blood and blood products, fibrous tissue and or calcium deposits

– Cause – No known cause, but progression linked hyperlipidemia, hypertension, cigarette smoking and diabetes mellitus

– Signs, Symptoms – None until significant stenosis

– Sonographic Appearance – Luminal irregularities, tortuosity, vessel wall calcification

Aorta Aneurysm

True Dilation of artery due to wall weakness Lined by all 3 components of artery wall

– Fusiform– Saccular

False Lined by outer layers of aortic wall or clot

– Dissecting– Pseudoaneurysm

Aneurysm - Patient Presentation

Causes– Atherosclerosis– Trauma– Syphilis– Marfan’s syndrome– Mycotic (Infective)

Clinical Features– Abdominal or back pain– Abdominal bruit– Pulsatile abdominal mass– Impaired distal arterial

flow

Dissecting Aortic Aneurysm

Type I– Ascending Aorta– Aortic Arch– Most dangerous [spiral]

Type II– Marfan’s Syndrome– Ascending Aorta– Aortic Arch

Type III– Descending Aorta– Abdominal Aorta

Aortic Aneurysm

Ultrasound Presentation

Endovascular Stent Graft

Medtronic Aneurx Cook Zentih Gore Excluder

Stent Graft Therapy

Stent Graft Therapy

Completed Deployment

Stent Graft Therapy

Pre – Stent Placement Post – Stent Placement

Stent Graft Therapy

Pre – Stent PlacementPost – Stent Placement

Aortic Rupture Risk Factors

Diameter Rapid expansion > 0.6 cm / year Family history Hypertension COPD, Current Smoking Shape:

Eccentric > Saccular> Fusiform

Inflammatory Aneurysms

Aneurysm enveloped by a dense fibrotic reaction

Uncommon – 5 to 20% of aneurysms Uncertain cause Clinically like other aneurysms

Branch Vessel Aneurysm

Splenic– Most common– Usually multiple & occur in main splenic trunk– Life threatening

Hepatic– 2nd most common– Right hepatic arterial branch – Common cause – systemic infection,

arteriosclerosis, blunt trauma– Silent or asymptomatic

Branch Vessel Aneurysm

SMA– Rarest [1 in 12,000]– Cause - cystic medial necrosis (mycotic aneurysm)– Intestinal angina & postprandial abdominal pain– General abdominal pain, fever

Renal Artery– Low incidence – approximately 20%– Symptoms – palpable mass, hypertension, blood in

urine, flank pain

Vascular Stenosis

Vessel lumen narrowed Post stenotic dilatation Increased velocities in area of stenosis Down stream changes

– Turbulence– Decreased velocities– Slowed acceleration during systole– Relative elevation of diastolic velocities

Abdominal Artery Evaluation

Doppler flow patterns [Angle corrected @ 60]– Aorta

Proximal – high systolic / low diastolic flow Distal – triphasic flow

– Celiac Axis Spectral broadening Unchanged after meals

– Hepatic Artery Spectral broadening

Arterial Flow Characteristics

Renal Artery Stenosis

– Associated with uncontrollable hypertension Up to 6% of all hypertensive patients have renal artery

stenosis as underlying cause

– Decreased glomerular filtration rate– Ischemic renal damage– Atherosclerotic plaque within first 2 cm– Fibromuscular dysplasia – lesions in distal 2/3 of

renal artery

Renal Artery Stenosis

Mesentery Artery Stenosis

Lack of adequate blood supply due to underlying vascular compromise

– Mesenteric atherosclerotic disease– Embolic phenomenon

Individuals at risk:– Smoking, coronary disease, PAD, chronic renal disease,

diabetes mellitus Symptoms:

– Progressive postprandial pain, weight loss, change in bowel habits, epigastrc bruit

Venous Flow Characteristics

Venous Abnormalities

Vena Caval Obstruction

Tumors of the IVC

Portal Venous Thrombosis

Portal Venous Hypertension

Vena Caval Obstruction

IVC site of clot or tumor Greenfield filter

– Reduce risk of clot embolizing

Renal Vein Thrombosis

Hepatic Venous Abnormalities

Budd-Chiari Syndrome– Occlusion of some or all

of the hepatic veins or occlusion of IVC

– Clinically – Ascites, right upper quadrant pain, hepatomegaly

– Sonographically – sluggish flow in IVC & hepatic veins

Portal Venous Abnormalities

Thrombosis Hypertension

Portosystemic Shunts

Portosystemic Shunts

Surgical end-to-side or side-to-side anastomosis of portal vein and IVC or TIPS

TIPS [Transjugular Interhepatic Portosystemic Shunts]

Abdominal Vasculature Review