Pelvic ureters
The pelvic part (pars pelvina ureteris) accounts for approximately half of the total length of the ureter. It begins at the pelvic brim and ends in the wall of the urinary bladder.
Course and syntopy features:
- At the level of the pelvic brim, the ureter appears as a flat cord about 0.5 cm wide. There is asymmetry here: on the left, it passes deeper than the common iliac artery (a. iliaca communis), while on the right, it crosses the external iliac artery (a. iliaca externa).
- In the pelvic cavity, the ureters descend along the lateral wall in the subperitoneal space. Medially lies the rectum, and laterally are the pelvic vessels and nerves.
- Heading towards the fundus of the bladder, they cross the obturator neurovascular bundle and the initial part of the umbilical artery.
- Bending anteriorly and medially, the ureters lie between the rectum and the urinary bladder, where they cross the vas deferens at a right angle (passing lateral to it).
- They penetrate the bladder wall obliquely: from top to bottom and outside in. They are surrounded by their own fascia and adipose tissue (paraureterium).
Prostate Gland
The prostate gland (prostata) is located in the subperitoneal floor and surrounds the initial part of the urethra. Anatomically, it consists of two lobes and an isthmus (the third lobe).
Topographic relationships:
- Superiorly: fundus of the urinary bladder, seminal vesicles, and ampullae of the vas deferens.
- Inferiorly: urogenital diaphragm.
- Anteriorly: posterior surface of the pubic symphysis (the gland is fixed to the bones by puboprostatic ligaments — ligg. puboprostatica).
- Posteriorly: ampulla of the rectum. The prostate is reliably separated from the rectum by the rectovesical fascia.
- Laterally: levator ani muscle (m. levator ani).
Externally, the organ is covered by the dense fascial capsule of Pirogov-Retzius. The excretory ducts of the gland (ductuli prostatici) open directly into the prostatic urethra.
Vas deferens
The pelvic segment of the vas deferens (pars pelvina ductus deferentis) begins at the deep inguinal ring and descends into the subperitoneal space of the lesser pelvis, running downwards and backwards.
Intersections system:
- First, the duct crosses the inferior epigastric artery (a. epigastrica inferior) and the external iliac vessels.
- Descending further, it crosses the obturator neurovascular bundle, as well as the umbilical and superior vesical arteries.
Passing medial to these vessels along the lateral wall of the bladder, the duct lies between the posterior wall of the bladder and the ureter. Its terminal part expands, forming the ampulla. The duct of the ampulla merges with the excretory duct of the seminal vesicle, thus forming the ejaculatory duct (ductus ejaculatorius), which penetrates the prostate and opens on the seminal colliculus.
Seminal Vesicles
The seminal vesicles (vesiculae seminales) are localized between the posterior wall of the urinary bladder and the anterior wall of the rectal ampulla. Like the prostate, they are separated from the rectum by the rectovesical fascia.
Syntopy and fascia:
- Medially, the ampullae of the vas deferens are adjacent to them.
- Laterally, they border the terminal parts of the ureters.
- The superior-medial parts of the vesicles are covered by the visceral peritoneum descending from the urinary bladder.
- The proper fascia of the vesicles is formed by the posterior layer of the visceral fascia of the urinary bladder.
Briefly: answers to topical questions
Where does lymphatic drainage from the prostate gland go?
Lymphatic drainage from the prostate gland goes to the pelvic lymph nodes located along the major vessels and on the bony structures. Lymph is directed to the following regional groups:
- Nodes along the internal iliac artery (a. iliaca interna).
- Nodes along the external iliac artery (a. iliaca externa).
- Nodes located on the pelvic surface of the sacrum.
What is the blood supply to the seminal vesicles?
The blood supply to the seminal vesicles is provided by:
- Inferior vesical artery (a. vesicalis inferior).
- Middle rectal artery (a. rectalis media).
Venous drainage from the seminal vesicles flows into the vesical venous plexus (plexus vesicalis).
To easily remember the syntopy of the prostate, picture it at the center of a "cross": pressed from above by the urinary bladder, supported from below by the urogenital diaphragm, protected in front by the pubic symphysis, and propped up behind by the rectum.
Class and exam questions
Where is the narrowest point of the pelvic ureter located?
It is located in the juxtavesical part — directly above the point where the ureter pierces the wall of the urinary bladder.
How is the ejaculatory duct formed?
It is formed by the confluence of the duct of the ampulla of the vas deferens and the excretory duct of the seminal vesicle. Afterward, it penetrates the thickness of the prostate gland.
What separates the prostate gland and seminal vesicles from the rectum?
The dense rectovesical fascia is located between these organs and the anterior wall of the rectal ampulla.
Where does venous drainage from the prostate gland go?
Blood collects into the prostatic venous plexus (plexus prostaticus), which then merges with the vesical plexus and empties into the internal iliac vein.
What else to study on this topic
- Blood supply to male pelvic organs: branches of the internal iliac arteries.
- Venous plexuses of the lesser pelvis and their anastomoses.
- Innervation of pelvic organs: the role of hypogastric plexuses and pelvic splanchnic nerves.
- Lymphatic drainage pathways from the prostate and seminal vesicles to the iliac and sacral nodes.
- Topography of ureteric crossings with blood vessels and the vas deferens.
Master the complete topic in the "Topographic Anatomy" course
This is a summary. The course covers everything tested in classes and exams.
- Complete study guide on "Topography of Male Pelvic Organs" and another 2,777 pages of the subject
- Assignments and quizzes after every topic — just like in a colloquium
- AI tutor answers questions on the topic anytime
- 91 video lessons on the subject
Other topics in the section "Topographic Anatomy of the Pelvis and Perineum"
Free video lessons: topographic anatomyShort lessons with study notes — no registration required.
Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.