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.

Outlines

00:00

📚 Anatomy of the Pelvic Region and Bladder

This paragraph delves into the anatomical structures of the pelvic region, focusing on the urinary bladder. It describes the bladder's position relative to the pelvis, the median umbilical ligament, and the medial umbilical ligaments. The speaker explains the concept of the prevesical space, also known as the 'cave of Retzius,' which is significant in medical procedures like suprapubic cystoscopy. The script also covers the peritoneum's reflection on the bladder and rectum, the rectovesical pouch, and the structures related to the bladder's posterior surface, such as the ureters and ductus deferens. Additionally, it touches on the blood supply to the bladder from the umbilical artery and the internal structure of the bladder, including the detrusor muscle and the trigone.

05:01

🩺 Urinary System Pathologies and Surgical Considerations

The second paragraph discusses various pathologies and surgical considerations related to the urinary system. It explains the mechanism of the ureteric orifices in the bladder, which helps prevent vesicoureteral reflux, and the potential complications that can arise when this mechanism fails. The paragraph also addresses the possibility of ureteric constriction due to stones and the associated conditions like hydroureter and hydronephrosis, illustrated with an axial CT scan example. Furthermore, it describes the internal urethral sphincter, its control by the sympathetic and parasympathetic nervous systems, and the implications of an enlarged prostate on the bladder's trigone. The summary concludes with the unique anatomical relationship between the ductus deferens and the ureters, and how this can sometimes lead to ureteric constriction.

Keywords

💡Urinary bladder

The urinary bladder is a hollow, muscular organ responsible for storing urine before it is excreted from the body. In the video's context, the bladder is being examined, with its apex and surrounding ligaments being described, highlighting its anatomical position and relationship with other structures.

💡Median umbilical ligament

The median umbilical ligament is a fibrous remnant of the urachus, a structure that connects the bladder to the umbilicus in the fetus. In the script, it is mentioned as a landmark that attaches to the umbilicus, indicating its developmental origin and location on the inner surface of the abdominal wall.

💡Medial umbilical ligaments

These are the obliterated distal portions of the umbilical artery, which are remnants of the fetal circulation. The script describes their position on either side of the median umbilical ligament, emphasizing their developmental significance and their route to the umbilicus.

💡Superficial inguinal fossa

The superficial inguinal fossa is a depression on the inner surface of the abdominal wall, lateral to the median umbilical ligament. The script mentions it as a potential site of herniation, indicating its clinical relevance in the context of abdominal wall weaknesses.

💡Prevesical space

The prevesical space, also known as the space of Retzius, is the area between the bladder and the pubic symphysis. It is filled with endopelvic fascia, as mentioned in the script, and is a critical anatomical space in procedures like suprapubic cystoscopy.

💡Detrusor muscle

The detrusor muscle is a smooth muscle layer in the wall of the bladder that contracts to expel urine during micturition. The script describes its function and control by the autonomic nervous system, emphasizing its role in bladder function.

💡Trigone

The trigone is a triangular area in the bladder where the ureters enter and the urethra originates. The script explains its importance in preventing vesicoureteral reflux and its sensitivity during cystoscopic examination, highlighting its clinical significance.

💡Urethral orifices

The urethral orifices are the openings where the ureters insert into the bladder. The script describes their beveled entry as a valvular mechanism to prevent reflux, and their clinical relevance in conditions like hydroureter and hydronephrosis.

💡Internal urethral sphincter

The internal urethral sphincter is a smooth muscle that encircles the internal urethral meatus and controls the flow of urine. The script explains its innervation and function in micturition, as well as its alteration in conditions like benign prostatic hyperplasia.

💡Ductus deferens

The ductus deferens is a tube that transports sperm from the epididymis to the ejaculatory ducts. The script describes its anatomical relationship with the ureters and its potential as a site of constriction, which is important for understanding male reproductive anatomy.

💡Benign prostatic hyperplasia

Benign prostatic hyperplasia is a non-cancerous enlargement of the prostate gland. The script discusses its impact on the bladder and urethra, including the formation of the uvula of the bladder and the post-prostatic pouch, which can lead to symptoms like nocturia and frequency.

Highlights

Introduction to the spring cadaver and the structures of the pelvis.

Identification of the urinary bladder and the median umbilical ligament.

Explanation of the median umbilical ligament's connection to the umbilicus.

Description of the medial umbilical ligaments and their origin from the umbilical artery.

Mention of the super of a cynical fossa as potential sites of herniation.

Discussion on the prevesical space and its contents, the endo pelvic fissure.

Clarification on the bladder's position relative to the pubic bone and the procedure of suprapubic cystoscopy.

Examination of the peritoneum covering the bladder and its reflection onto the rectum.

Introduction to the rectovesical pouch and its significance in females.

Differentiation between the fundus and apex of the bladder and their anatomical relations.

Identification of the structures related to the posterior surface of the bladder: the ductus deferens, ureters, and seminal vesicles.

Demonstration of the relationship between the ductus deferens and the ureters.

Explanation of the blood supply to the bladder from the umbilical artery.

Interior examination of the bladder, focusing on the bladder mucosa and detrusor muscle.

Description of the trigone of the bladder and its role in preventing vesicoureteral reflux.

Importance of the internal urethral sphincter in the process of micturition.

Discussion on the impact of benign hypertrophy of the prostate on the bladder and urethra.

Identification of the post-prostatic pouch and its role in nocturia and frequency.

Conclusion summarizing the key points about the bladder and related structures in the pelvis.

Transcripts

[Music]

so this is spring cadaver I'm on the

right side camera person is on the left

side we have completely taken all the

structures of the pelvis and this

structure that we see in front of us

this is the urinary bladder

this is apex of the bladder and we can

see this ligament arising from the apex

this is the median umbilical ligament

which is a remnant of the erectus which

is derived from the allen toy and this

goes and gets attached to the umbilicus

on the inner surface of the a abdominal

wall we see these two ligaments on

either side these are the medial

umbilical ligaments which are the

obliterated distal portions of the

umbilical artery which is a branch from

the anterior division of the internal

iliac these also go to the umbilicus in

life these structures are located on the

inner surface of the a tree abdominal

wall and there's a depression on either

side of the median umbilical ligament

here and here these are called the super

of a cynical fossa which can be a

potential site of herniation to continue

we have opened out the space between the

bladder and the pubic symphysis this is

known as the previous cycle space this

is filled with endo pelvic fissure this

space is also referred to as the cave of

radius in life this is filled with

recycled venous plexus which becomes

continuous with the prosthetic venous

plexus normally the bladder is below the

level of the pubic bone intra pelvic

organ but when the bladder gets

distended and for some reason we cannot

pass the catheter through the urinary

passage we have to do what is known as a

suprapubic cystoscopy

and we do the suprapubic just talk to me

through this route where my instrument

is pointing to continue with the parts

of the bladder this surface of the

bladder was covered by peritoneum and

this is the Dome of the bladder and this

peritoneum which we have removed

continues and gets reflected onto the

rectum which is this structure here the

place where the peritoneum gets

reflected from the bladder to the rectum

that is known as the rec to recycle

pouch in females Sutras is lying on the

Dome of the bladder so therefore there

will be a Vista Co you trained publish

any portion after that is extra pet

oniel and we will come to that in a

little

while we will pick up the better to show

you this portion Knox ocean is known as

the fundus it is extra paid to name the

fundus of the bladder is also called the

pace of the bladder because it is

opposite the apex it is also the

posterior surface of the bladder this is

the structure which is in relation to

the rectum separated by the recto of a

cycle set and it contains three

structures in the main and we can see

the two structures here one of them is

the doctors difference which is going

inside and then we have the ureter which

is also going and there will be a

structure which is not visible but

further lower down and that'll be the

seminal vesicle so this are the three

structures which are separating the

posterior surface or the base of the

bladder from the rectum and the rector

of a cycle septum and to show it more

clearly I will lift up the bladder and

we can see this is the doctors

difference here on this side and the

doctors difference on this side and we

can see the doctors difference here

becomes a little dilated this is known

as the ampule of the doctors difference

which will then unite with the duct from

the seminal blade and form the gamma D

regulatory duct which will go through

the prostate and open as the common

ejaculatory duct into the prostate in

your instrument this is a post-operative

case so therefore this whole area was

highly fibrosis but we can see a few of

the blood vessels which are coming to

the bladder from the proximal portion of

the umbilical artery and these are the

severe recycle arteries on this side and

these are some remnants of the severe

recycle artery on this side they are the

ones we supply the dome of the bladder

the ductus deferens it's supplied by

branch from the inferior recycle artery

and these are known as differential

arteries ninfea recycle artery is also

approached from the anterior division of

the internal iliac now let's take a look

at the interior of the bladder and for

that we have sliced open the bladder on

its anterior surface and I have tilted

the bladder back and we have opened the

letter

this is the interior of the matter we

can see first of all the bladder mucosa

it is sewn into slight folds after that

this is the thickness of the bladder

wall this contains a smooth muscle which

is referred to as the detrusor muscle

this detrusor muscle is under

parasympathetic control parasympathetic

causes contraction and sympathetic

causes relaxation of the bladder and if

we look very closely here we can see a

triangular shaped structure here this is

the Trigon of the bladder this tricone

is located in the floor of the bladder

what are the components of this Trico

you can see this structure which I have

lifted up here and when I pull we can

see it is exerting attraction on the

ureter on this side similarly when I

pull here we can see it is exerting

traction on the ureter on this side so

these are the openings of the two

ureters the ureters went into the

bladder to enter in a bevelled fashion

the purpose being to prevent vistacool

euroleague reflux in normal

circumstances therefore it acts as a

valvular mechanism with this valve Aloma

cancer fails then we get what I

mentioned as the visco urinary reflux

for the same reason this you drove a

cycle Junction is also a potential site

of European constriction where a small

stone more than 0.5 centimeters can get

impacted in which case there will be

hydro ureter and hydronephrosis this is

an axial CT scan at the level of the hip

joint to show a right you Egypt calculus

and right hydro ureter if we look

further closely we will see a rich

joining the two openings of the ureters

this is referred to as the inter

ureteric bar lower down we can see yet

another opening here that is the opening

of the urethra that is the internal

urethral meatus

which is also encircled by smooth muscle

which is the internal urethral sphincter

this is relaxed by the spatter

sympathetic and contracted by the

sympathetic

so therefore parasympathetic is for

micturition purpose this try goal of the

bladder is derived separately from the

rest of the bladder

bladder is derived from inter term of

the urogenital sinus why the tricone is

derived from the me suit

wolffian dumped mucosa of the trigon is

very sensitive when we are doing a you

know trance copy examination of the

bladder and we reach the internal

urethral meatus at that position we

cannot see normally the two openings of

the ureter however when we advance the

urine through scope even further then we

can see these two openings that is the

normal situation however when the

patient has got benign hypertrophy of

the prostate then the internal urethral

orifice is pushed up by means of the

median lobe of the prostate and that is

referred to as the uvula of the bladder

and in which case we get a condition

known as Marion's sine positive

what is this Merion sign positive it

means that in the same system urethral

scopic view we can see all the three

orifices simultaneously so when a

patient has got enlarged prostate the

median lobe is enlarged there is a

depression behind the median lobe of the

prostate and that is known as the post

prostatic pouch

whenever the patient lies down there is

irritation of the post prostatic pouch

the trigana of the bladder by means of

residual urine and that is what produces

nocturia

and frequency in a patient with benign

hypertrophy of the prostate again come

to the posterior surface or the base of

the bladder to show the unique

relationship of the ductus deferens and

the ureter so I have pulled it up to

show you the normal relationship and we

can see that the ureters are crossed

over by the ductus deferens on either

side this is because during embryonic

life the testes descends down and the

kidneys ascent up and so therefore this

is the place where the ductus deferens

crosses the ureter this can rarely be a

site of constriction of the ureter where

again a stone can get impacted so these

are the points that are already

mentioned to you about the better and

the related structures in the pelvis