URINARY BLADDER CADAVERIC DISSECTION - Human Anatomy Cadaveric Dissection Videos

Summary

This educational video script delves into the anatomy of the urinary bladder, highlighting its structure, ligaments, and relationship with surrounding organs. It explains the median umbilical ligament, medial umbilical ligaments, and the potential hernia sites. The script also covers the bladder's interior, including the detrusor muscle, trigone, and the urethral and ureteral orifices. It discusses conditions like urinary reflux and benign prostatic hyperplasia, providing insights into the bladder's function and potential medical issues.

Takeaways

• 📚 The script discusses the anatomy of the urinary bladder and its surrounding structures in a cadaveric dissection setting.
• 🔍 The median umbilical ligament is identified, which is a remnant of the urachus and attaches to the umbilicus.
• 🔑 The medial umbilical ligaments are remnants of the obliterated umbilical artery, branching from the internal iliac artery.
• 🕳 The presence of the superolateral fossa, a potential site for herniation, is mentioned on either side of the median umbilical ligament.
• 🌐 The prevesical space, also known as the space of Retzius, is described, which contains the endopelvic fascia in life.
• 💡 The bladder's position relative to the pubic bone and the procedure of suprapubic cystoscopy is explained for distended bladders.
• 🌌 The peritoneum covering the bladder and its reflection onto the rectum, known as the rectovesical pouch, is discussed.
• 🌀 The fundus of the bladder, which is extraperitoneal and opposite the apex, is identified along with its relation to the rectum.
• 🚰 The interior of the bladder is described, including the mucosa, the detrusor muscle, and the trigone.
• 🚿 The trigone's role in preventing vesicoureteral reflux and its sensitivity during cystoscopy is highlighted.
• 🌡 The anatomical relationship between the ureters, ductus deferens, and the urethra, including potential sites for constriction and impaction, is explained.

Q & A

What is the median umbilical ligament and what is its embryonic origin?

The median umbilical ligament is a remnant of the urachus, which is derived from the allantois. It extends from the apex of the bladder to the umbilicus on the inner surface of the abdominal wall.

What are the medial umbilical ligaments and their function in the body?

The medial umbilical ligaments are the obliterated distal portions of the umbilical artery, which is a branch from the anterior division of the internal iliac artery. They also extend to the umbilicus and are located on the inner surface of the abdominal wall.

What is the clinical significance of the supero-anterior fossa in the abdominal wall?

The supero-anterior fossa is a depression on either side of the median umbilical ligament and can be a potential site for herniation.

What is the pre-vesical space and its contents in the body?

The pre-vesical space, also known as the cave of Retzius, is located between the bladder and the pubic symphysis and is filled with the endo-pelvic fascia in life, which becomes continuous with the prostatic venous plexus.

Why is a suprapubic cystoscopy performed and through which route is it done?

A suprapubic cystoscopy is performed when the bladder is distended and the catheter cannot be passed through the urinary passage. It is done through the pre-vesical space, above the level of the pubic bone.

What is the relationship between the peritoneum covering the bladder and the rectum?

The peritoneum covering the bladder's surface continues and gets reflected onto the rectum, forming the recto-vesical pouch in females and the recto-prostatic pouch in males.

What are the structures separating the posterior surface of the bladder from the rectum?

The structures separating the posterior surface of the bladder from the rectum are the ductus deferens, the ureters, and the seminal vesicles, which are contained within the recto-vesical or recto-prostatic septum.

What is the significance of the ampulla of the ductus deferens and its connection to the seminal vesicles?

The ampulla of the ductus deferens dilates and unites with the duct from the seminal vesicle to form the ejaculatory duct, which passes through the prostate and opens into the urethra.

How does the blood supply to the bladder dome differ from the rest of the bladder?

The blood supply to the dome of the bladder comes from the vesical arteries, which are branches of the anterior division of the internal iliac artery, whereas the rest of the bladder is supplied by other branches.

What is the detrusor muscle and what is its autonomic nervous system control?

The detrusor muscle is a smooth muscle that forms the wall of the bladder. It is under parasympathetic control, which causes contraction, and sympathetic control, which causes relaxation, facilitating the process of micturition.

What is the trigone of the bladder and what are its components?

The trigone is a triangular shaped structure located in the floor of the bladder. It includes the openings of the two ureters and the internal urethral meatus, and is encircled by the internal urethral sphincter.

What is the clinical significance of the inter-ureteric bar and the internal urethral meatus?

The inter-ureteric bar is a part of the trigone and is important for the anatomy of the bladder. The internal urethral meatus is the opening of the urethra within the bladder and is surrounded by the internal urethral sphincter, which is crucial for controlling the flow of urine.

What is the significance of the relationship between the ureters and the ductus deferens?

The ureters cross over the ductus deferens on either side because during embryonic life, the testes descend while the kidneys ascend. This anatomical relationship can rarely cause constriction of the ureter where a stone might get impacted.

What is Marion's sign positive and what does it indicate in a patient with benign hypertrophy of the prostate?

Marion's sign positive refers to a condition where all three orifices (the two ureteral openings and the internal urethral meatus) are visible simultaneously during a cystoscopic examination. This indicates that the internal urethral orifice is pushed up by the enlarged median lobe of the prostate, causing a depression known as the uvula of the bladder.

What is the post-prostatic pouch and its clinical significance?

The post-prostatic pouch is a depression behind the median lobe of the prostate. Irritation of this pouch by residual urine when the patient lies down can produce nocturia and frequency in patients with benign hypertrophy of the prostate.