The superior vesical artery is a blood vessel that supplies oxygenated blood to the upper part of the urinary bladder and portions of the ureter. It originates from the anterior division of the internal iliac artery, often as a continuation of the umbilical artery. In addition to the bladder, it sometimes contributes to the blood supply of the vas deferens in males.
Location
The superior vesical artery is located in the pelvis. It arises from the internal iliac artery, typically from the obliterated portion of the umbilical artery, which becomes a fibrous cord after birth. It courses medially towards the upper portion of the urinary bladder, distributing branches to the bladder wall. The artery also sends small branches to the distal ureter, contributing to its blood supply. In males, it can also provide blood to the vas deferens as part of the male reproductive system.
Structure and Anatomy
The superior vesical artery is an important vessel within the pelvic region, supplying blood primarily to the upper part of the bladder. Its anatomy reflects its role in ensuring the bladder and adjacent structures are adequately perfused. Below is a detailed description of its anatomical features.
Origin
The superior vesical artery typically originates from the anterior division of the internal iliac artery, which is one of the major arteries supplying the pelvic organs. In most cases, the superior vesical artery is a continuation of the patent portion of the umbilical artery. After birth, the distal part of the umbilical artery becomes obliterated and forms the medial umbilical ligament, but the proximal part remains functional as the superior vesical artery.
Course
Once the superior vesical artery branches off from the internal iliac artery, it travels medially towards the bladder. Its course is relatively short, as it directly approaches the upper part of the bladder. The artery passes through the pelvic fascia and runs along the lateral aspect of the bladder, distributing smaller branches that supply the bladder’s dome and upper sections.
The artery courses within the lateral vesical ligament, a structure that helps support the bladder and contains blood vessels, nerves, and connective tissue.
Branches
The superior vesical artery gives rise to several branches that provide blood to specific regions within the pelvis:
- Bladder Branches: These branches primarily supply the upper part of the bladder, including the dome and upper bladder wall. The branches penetrate the detrusor muscle (the muscle responsible for bladder contractions) and supply the mucosa, submucosa, and muscle layers.
- Ureteral Branches: In addition to supplying the bladder, the superior vesical artery gives off small branches that supply the upper portion of the ureter, particularly near its insertion into the bladder.
- Vas Deferens Branch (Males): In males, the superior vesical artery often gives off small branches to the vas deferens, which is the duct that carries sperm from the testicles to the urethra.
Variations
There may be anatomical variations in the superior vesical artery’s origin and branching patterns. Although it most commonly arises from the anterior division of the internal iliac artery, it may have alternative origins:
- Common Trunk with Inferior Vesical Artery: In some cases, the superior vesical artery may share a common origin with the inferior vesical artery or another pelvic vessel.
- Additional Bladder Supply: Sometimes, multiple superior vesical arteries can be present, especially in cases where additional blood supply to the bladder is required.
Anastomoses
The superior vesical artery forms important anastomoses with nearby arteries, ensuring a well-perfused network in the pelvic region:
- Inferior Vesical Artery: In males, the superior vesical artery anastomoses with the inferior vesical artery, which supplies the lower portion of the bladder and the prostate.
- Obturator Artery: The superior vesical artery sometimes forms connections with branches of the obturator artery, which supplies the medial thigh and parts of the pelvic wall.
- Uterine Artery (Females): In females, the superior vesical artery may form anastomoses with the uterine artery, which supplies the uterus and upper vagina. This connection helps to ensure consistent blood flow to the pelvic organs, particularly in cases of increased blood demand, such as during pregnancy.
Relations to Other Structures
The superior vesical artery is anatomically related to several important pelvic structures:
- Bladder: The artery primarily supplies the upper portion of the bladder and runs along its lateral surface.
- Ureter: The superior vesical artery gives off small branches to the ureter, particularly near the point where the ureter inserts into the bladder. This relationship is important in maintaining a proper blood supply to the ureter and bladder junction.
- Medial Umbilical Ligament: The superior vesical artery arises near the medial umbilical ligament, which represents the remnant of the obliterated umbilical artery.
- Pelvic Fascia: The artery runs within the pelvic fascia, alongside other vessels and nerves that support the bladder and surrounding pelvic organs.
Sex-Specific Anatomy
The anatomy of the superior vesical artery exhibits slight differences between males and females:
- Males: In males, the artery often gives off branches to the vas deferens, supplying part of the male reproductive tract. It also forms important anastomoses with the inferior vesical artery, which supplies the prostate and seminal vesicles.
- Females: In females, the superior vesical artery may form connections with the uterine artery. This anastomosis helps to maintain an adequate blood supply to the uterus and upper parts of the vagina.
Anatomical Variability and Clinical Relevance
The superior vesical artery’s anatomical course and branching pattern can vary between individuals, although its primary function of supplying the upper bladder remains consistent. Its proximity to key structures like the ureter, bladder, and pelvic fascia underscores the importance of understanding its detailed anatomy, particularly in surgical procedures involving the bladder or pelvic region.
Function
The superior vesical artery serves essential roles in maintaining the blood supply to the urinary bladder and other pelvic structures. Below is a detailed explanation of the functions of this artery.
Blood Supply to the Upper Urinary Bladder
The primary function of the superior vesical artery is to provide oxygenated blood to the upper part of the urinary bladder, including the bladder dome and upper bladder wall. This blood supply is essential for maintaining the bladder’s structural integrity, enabling it to store and expel urine effectively. The bladder’s muscular layer, the detrusor muscle, relies on the blood delivered by the superior vesical artery to function properly during the storage phase of urine and during urination. This continuous blood flow ensures that the bladder tissue receives the necessary nutrients and oxygen for healthy function.
Bladder Dome Perfusion: The superior vesical artery provides a robust blood supply to the dome of the bladder, which is crucial for its ability to expand and contract as it stores and releases urine.
Support During Bladder Filling and Emptying
During bladder filling and emptying, the superior vesical artery supports the detrusor muscle, the smooth muscle responsible for contracting and relaxing to expel urine. The artery ensures that the detrusor muscle has sufficient oxygenated blood to maintain its tone and function properly during the micturition process. This is particularly important because the bladder must be able to expand significantly during filling and then contract forcefully during urination, both of which require a reliable blood supply.
Detrusor Muscle Support: By supplying the upper bladder, the superior vesical artery indirectly ensures the bladder can fill and empty efficiently.
Blood Supply to the Ureter
The superior vesical artery also plays a key role in supplying the upper portion of the ureter, specifically the area where the ureter inserts into the bladder. The ureter is responsible for transporting urine from the kidneys to the bladder, and the segment closest to the bladder requires sufficient blood flow to maintain its functional integrity. The small branches of the superior vesical artery that supply the ureter ensure that this structure is well-nourished, supporting its smooth muscle contractions, which help propel urine from the kidneys into the bladder.
Ureteral Support: The artery’s contribution to the ureter’s blood supply is essential for its ability to transport urine efficiently into the bladder.
Blood Supply to the Vas Deferens (Males)
In males, the superior vesical artery contributes to the blood supply of the vas deferens, the duct responsible for transporting sperm from the testes to the urethra during ejaculation. By providing blood to the vas deferens, the superior vesical artery supports the health and function of the male reproductive tract, ensuring that the vas deferens can perform its role in sperm transport during ejaculation.
Reproductive System Support (Males): The superior vesical artery helps ensure that the vas deferens remains well-perfused and functional, contributing to male fertility.
Contribution to Pelvic Vascular Network
The superior vesical artery is part of the extensive pelvic vascular network. Through its anastomoses with other arteries, it contributes to the overall perfusion of the bladder, pelvic organs, and surrounding structures. This redundancy in blood supply ensures that if one artery is compromised, other arteries can compensate to maintain adequate blood flow.
- Anastomosis with Inferior Vesical Artery (Males): In males, the superior vesical artery forms important connections with the inferior vesical artery, ensuring that both the upper and lower portions of the bladder, as well as the prostate, receive a continuous blood supply.
- Anastomosis with Uterine Artery (Females): In females, the superior vesical artery may connect with the uterine artery, providing additional blood flow to the bladder and possibly the uterus, especially during pregnancy when there is an increased demand for blood.
Tissue Repair and Regeneration
The superior vesical artery plays an essential role in tissue repair and regeneration within the bladder. In cases of bladder trauma, surgery, or after infections, the artery supplies the blood necessary for healing and recovery. Oxygen and nutrients delivered by the artery support cell regeneration and repair of the bladder’s mucosal and muscular layers.
Healing Support: Whether following surgery or injury, the superior vesical artery ensures that the bladder tissues have the resources they need for rapid and effective healing.
Maintenance of Bladder Health During Aging
As people age, the bladder can undergo structural changes, including weakening of the bladder wall and reduced elasticity. The superior vesical artery plays an important role in ensuring that the bladder remains well-perfused, which can help maintain bladder health as it undergoes age-related changes. The artery’s ability to supply oxygenated blood to the bladder helps sustain tissue vitality, preventing atrophy and supporting normal bladder function for as long as possible.
Bladder Health Preservation: The continuous supply of blood from the superior vesical artery helps maintain bladder function and integrity, even as age-related changes affect pelvic organs.
Clinical Significance
The superior vesical artery is clinically significant due to its role in supplying blood to the upper bladder and portions of the ureter. Its importance is especially relevant in surgical procedures involving the bladder, such as bladder surgeries for cancer, trauma, or reconstruction. Injury to this artery during surgery can result in excessive bleeding or inadequate blood supply to the bladder, leading to ischemia or delayed healing.
In males, the superior vesical artery also contributes to the blood supply of the vas deferens, making it relevant in surgeries related to the reproductive tract, such as vasectomy or treatments for male infertility. Additionally, the artery’s role in forming anastomoses with other pelvic arteries, such as the inferior vesical and uterine arteries, makes it a key vessel in maintaining a robust vascular network within the pelvis. Disruption of this blood flow can compromise the function of multiple pelvic organs.
