Here are the paths and locations of the large pelvic arteries, the aorta, and the cisterna chyli:
Aorta:
The aorta is the largest artery in the body and originates from the left ventricle of the heart.
It descends posterior to the heart, passes through the thoracic and abdominal cavities, and eventually bifurcates into the left and right common iliac arteries at the level of the fourth lumbar vertebra.
Common Iliac Arteries:
The common iliac arteries are the major branches of the abdominal aorta.
They bifurcate from the aorta at the level of the fourth lumbar vertebra.
Each common iliac artery divides into the internal and external iliac arteries.
Internal Iliac Arteries:
The internal iliac arteries supply blood to the pelvic organs, gluteal region, and perineum.
They originate from the common iliac arteries and pass posteriorly into the pelvis, dividing into various branches to supply different pelvic structures.
External Iliac Arteries:
The external iliac arteries supply blood to the lower limbs.
They originate from the common iliac arteries and pass inferiorly along the pelvic sidewalls, eventually crossing the inguinal ligament to become the femoral arteries.
Cisterna Chyli:
The cisterna chyli is a dilated lymphatic sac located in the retroperitoneal space, anterior to the lumbar vertebrae (usually between the first and second lumbar vertebrae).
It serves as a reservoir for lymphatic fluid from the lower limbs, pelvis, and abdomen, before draining into the thoracic duct.
The thoracic duct ascends through the abdomen and enters the thoracic cavity, eventually emptying into the venous system near the junction of the left subclavian and internal jugular veins.
Understanding the path and location of these arteries and lymphatic structures is crucial for understanding the blood supply and lymphatic drainage of the pelvic region, as well as for clinical assessments and interventions in this area.
The path and location of the outer, inner, and common pelvic lymph nodes, as well as the lumbar lymph nodes, are as follows:
Outer Pelvic Lymph Nodes:
Superficial Inguinal Lymph Nodes: Located in the groin region, these nodes receive lymphatic drainage from the lower limbs, perineum, and external genitalia.
Inner Pelvic Lymph Nodes:
Internal Iliac Lymph Nodes: Situated within the pelvis, these nodes receive lymphatic drainage from pelvic organs such as the bladder, rectum, and reproductive organs.
Common Pelvic Lymph Nodes:
External Iliac Lymph Nodes: Located along the external iliac arteries, these nodes receive lymphatic drainage from the lower limbs and pelvic wall before draining into the common iliac nodes.
Common Iliac Lymph Nodes: Situated at the bifurcation of the common iliac arteries, these nodes receive lymphatic drainage from the external and internal iliac nodes before continuing to the lumbar nodes and eventually the cisterna chyli.
Lumbar Lymph Nodes:
Lumbar Lymph Nodes: Found along the abdominal aorta and the inferior vena cava, these nodes receive lymphatic drainage from the pelvis, lower abdomen, and lower limbs. They play a crucial role in filtering lymph and facilitating its return to the bloodstream via the thoracic duct or right lymphatic duct.
Understanding the path and location of these pelvic and lumbar lymph nodes is essential for diagnosing and treating conditions such as pelvic cancers, infections, and lymphatic disorders.
Location of Cisterna Chyli:
The cisterna chyli is a dilated lymphatic sac located in the abdomen, anterior to the first and second lumbar vertebrae, near the origin of the abdominal aorta. It serves as a reservoir for lymphatic fluid and is a key structure in the lymphatic system.