Medical Sonography Program - Abdominal Vascular Anatomy

Abdominal Vascular Anatomy

Hepatic Veins

Phrenic Artery

Coeliac Axis

Gastric Artery

Hepatic Artery

Right Renal Artery

Right Kidney

Right Ureter

Inferior Vena Cava

Right Common Iliac Artery

Right External Iliac Artery and Vein

Spleen

Splenic Artery

Suprarenal Gland

Left Renal Artery

Left Kidney

Left Renal Vein

Superior Mesenteric Artery

Inferior Mesenteric Artery

Left Internal Iliac Artery and Vein

Content Overview

• Aorta, IVC, Portal Venous System, Abdominal ligaments described.

• Description, location, function of each system.

• Atlas of Anatomy (videos) for review.

• Diagram and Sonographic Appearance.

• Visual aids being used.

• Poll Everywhere activity after the lecture.

Abdominal Aorta

• Retroperitoneal structure: Lies outside the peritoneum, which is the membrane that lines the abdominal cavity and covers the abdominal organs.

• Located in the retroperitoneal space, a region behind intraperitoneal organs like the stomach and intestines.

• Carries oxygenated blood from the heart to the rest of the body.

The Abdominal Aorta & Its Branches

• Video resource: Acland's Video Atlas of Human Anatomy. Arteries of the abdominal region.

Abdominal Aorta & Branches

• Unpaired branches:

  • Celiac.

  • Superior mesenteric.

  • Inferior mesenteric.

  • Median sacral.

• Paired branches:

  • Middle suprarenal (adrenal).

  • Renal.

  • Gonadal (testicular or ovarian).

  • Inferior phrenic.

  • Lumbar.

  • Common iliac.

Abdominal Vascular Anatomy - Aorta

Abdominal Aortic Branches

Inferior Phrenic Arteries

Celiac Trunk/Celiac Artery (CA)

Suprarenal Branches

Superior Mesenteric Artery (SMA)

Abdominal Aortic Branches - Juxtarenal Branches

Renal Arteries

Abdominal Aortic Branches - Infrarenal Branches

Gonadal Arteries

Inferior Mesenteric Artery (IMA)

Median Sacral Artery (MSA)

Common Iliac Arteries (CIA)

Abdominal Aorta & IVC

Diagram showing various arteries and their relative positions

Celiac Trunk Branches

Left Gastric Artery (LGA)

• Courses superior left.

• Supplies proximal part of the stomach's lesser curvature and the distal esophagus; anastomoses with the right gastric artery (RGA - branch of the CHA).

Splenic Artery (SPA)

• Courses horizontally to the left, slight inferior superior angulation.

• Supplies the spleen, left side of greater curvature of stomach, and pancreas (main, dorsal, caudal, and great pancreatic arteries).

Celiac Trunk (artery)

• Key artery supplying blood to the foregut and its derivatives.

• Branches: 1) Left Gastric artery 2) Splenic artery 3) Common Hepatic artery

• SMA is used as a landmark in locating the celiac trunk

Common Hepatic Artery (CHA)

• Courses horizontally to the right.

• Branches:

  • Gastroduodenal artery (GDA): Courses inferiorly. Supplies the right side of the greater curvature of the stomach, duodenum, pancreas

  • Proper hepatic artery (PHA): Courses laterally to the right and superiorly. Branches into the right, middle, and left hepatic arteries. Branch of PHA –> right gastric artery(RGA) Supplies the left and right lobes of the liver, gallbladder (cystic artery), right side of the lesser curvature of the stomach (RGA).

Abdominal Aorta Branches Video

• Video resource.

Aorta & Branches - Sonographic Appearance

Proximal Aorta

• Transverse View: Rounded pulsatile structure to the left of the spine.

• Sagittal View: Originates from the heart, travels superiorly, arches posteriorly to form the aortic arch, then descends through the thorax as the descending aorta. Continues into the abdomen as the abdominal aorta, eventually bifurcating into the common iliac arteries.

Diagrams illustrating ultrasound imaging of the aorta and its branches

Aorta Diagnostic Tests

• Duplex Doppler Ultrasound

• Color Doppler

• Impedance Flow Plethysmography

• Arteriography

• Computed Tomography (CT)

• Magnetic Resonance (MRI)

The Inferior Vena Cava (IVC)

• Retroperitoneal structure.

• Lies outside the peritoneum on the posterior abdominal wall, along the right side of the vertebral column.

• Located to the right of the abdominal aorta.

• Carries deoxygenated blood from the lower body back to the heart.

The Inferior Vena Cava (IVC) - Video

• Video resource: Acland's Video Atlas of Human Anatomy on veins of the abdominal region.

Inferior Vena Cava (IVC) - Vein Sections

Vein Details

IVC Branches

• Left Renal Vein (LRV)

  • Location: Left lateral to IVC

  • Course: Posterior to part of the SPV, and pancreas tail. Runs between the AO and the SMA.

  • Tributaries: Intrarenal arteries, Left suprarenal vein

  • Function: Drains the left kidney

    • Note: Left suprarenal vein typically drains into the left renal vein, which then drains into the IVC.

• Left suprarenal vein

  • Begins at the hilum (central part) of the left adrenal gland.

  • Travels vertically, unlike the shorter, horizontal course of the right suprarenal vein.

  • Empties into the left renal vein, which then drains into the IVC.

  • Drains venous blood from the left adrenal gland

• Left Gonadal Vein

  • Lateral left to the IVC

  • Superior

  • Empties into the LRV

• Hepatic Veins

  • Intrahepatic

  • From inferior deep within the liver to superior in the liver.

  • Drain into the IVC

    • RHV: Drains segments 6, 7, 8

    • MHV: Drains segments 4B & 5

    • LHV: Drains segments 2, 3, 4A - divides the liver into medial and lateral segments

IVC Drainage Scheme & Relations

• Scheme of Drainage:

  • Heart

    • Hepatic veins

      • Hepatic portal vein

    • Right renal, Suprarenal, Left renal

      • Inferior phrenic

    • Right gonadal, Left gonadal, Lumbar

      • Inferior vena cava

        • Right common iliac, Left common iliac

          • Right external iliac, Right internal iliac, Left external iliac, Left internal iliac

• Relations of IVC

  • Anterior: Bile duct, liver, opening of lesser sac, 1st/3rd parts of duodenum, head of pancreas, small bowel, right common iliac artery, root of mesentery, right gonadal artery, portal vein

  • Posterior: Right renal artery, lumbar arteries, right crus of diaphragm, right suprarenal & its artery, bodies of L3,4,5, right psoas, right sympathetic chain, right coeliac ganglion

  • Note: NO tributaries from gut

Diagrams showing the IVC and its tributary relations to nearby organs.

IVC - Sonographic Appearance

Diagrams explaining ultrasound findings and relation to the liver.

IVC - Diagnostic Tests

• Duplex Doppler Ultrasound

• Color Doppler

• Impedance Flow Plethysmography

• Venography

• Computed Tomography (CT)

• Magnetic Resonance (MRI)

Diagrams showing Doppler ultrasound readings

The Portal Venous System

• Specialized circulatory pathway where venous blood from the digestive organs, spleen, and pancreas drains into the liver before entering the general circulation.

• Ensures that nutrients absorbed from digested food and potential toxins are first processed by the liver before being distributed to the rest of the body.

The Portal Venous System - Video

• Video resource: Acland's Video Atlas of Human Anatomy on the veins of the abdominal organs.

The Portal Venous System - Details

• The Portal Venous system:

  • Splenic vein

  • Pancreatic veins

  • Gallbladder veins

  • GI veins

  • Carries blood and nutrients from the bowel and abdominal organs to the liver for metabolism and detoxification.

• SMV passes anterior to the third part of the duodenum and posterior to the neck of the pancreas

Ductus Venosus

• A fetal blood vessel that connects the Umbilical vein to the Inferior Vena Cava

• It's essentially a shunt, allowing oxygenated blood from the placenta to bypass the liver and go directly to the heart.

• This shunt is crucial for fetal circulation and proper oxygen delivery.

• After birth, the ductus venosus typically closes and becomes the Ligamentum Venosum.

Ligamentum Venosum

• Is a fibrous band located on the posterior surface of the liver, specifically between the caudate lobe and the left lobe.

• It represents the thrombosed remnant of the fetal Ductus Venosus, which shunted blood directly from the Umbilical vein to the IVC, bypassing the liver in utero.

Falciform Ligament

• From Latin 'sickle-shaped’

• ligament that attaches the liver to the anterior abdominal wall

• divides the liver into the left lobe and right lobe

• It’s a broad and thin fold of peritoneum

• It's a remnant of the embryonic ventral mesentery.

Ligamentum Teres Hepatis

• AKA the Round ligament of the liver, is a fibrous cord that runs from the umbilicus to the liver, a remnant of the Left Umbilical vein.

• It's part of the Falciform ligament, located in the free edge of the falciform ligament

• Key structure in the abdomen, connecting the umbilicus to the liver.

Diagrams of the portal venous system and ligaments.

Portal Venous System - Sonographic Appearance

Diagrams and illustrations depicting ultrasound imaging of the portal venous system and its relation with the liver.

Portal Venous System - Diagnostic Tests

• Duplex Doppler Ultrasound

• Color Doppler

• Direct Portal Venography

• Computed Tomography (CT)

• Magnetic Resonance (MRI)

Diagrams and doppler ultrasound readout and anatomical references.