17. Male Reproductive System Flashcards
List examples of Pathologies of the Male Reproductive System?
Sub - Fertility Infection Torsion Cancer Benign Prostatic Hypertrophy Erectile Dysfunction
List examples of Abnormalities of the Male Reproductive System?
Hydrocoele Varicocoele Hypospadias Epispadias Cryptorchidism Epididymo - Orchitis
What is the Ejaculation Pathway of Sperm?
SEVEn UP:
- Seminiferous Tubules
- Epididymis
- Vas Deferens
- Ejaculatory Ducts
- Urethra
- Penis
Which 5 Anatomical Structures constitute the External Genitalia?
- Testes
- Epididymis
- Spermatic Cord
- Scrotum
- Penis
What is the Involuntary Muscle of the Scrotum?
Tunica Dartos
What is the Function of the Tunica Dartos?
Contracts to Wrinkle the Scrotal Skin.
This Decreases the Surface Area reducing Heat Loss.
Regulates the Temperature of the Testicles which promote Spermatogenesis.
Which other Muscles performs the same function as the Dartos?
The Cremaster Muscle which is over the Testes.
What is the Female equivalent of the Scrotum?
Labia Majora
What does the Labia Majora contain?
- Round Ligament
- Fat
- Sweat Glands
- Oil Glands
Where do the Lymphatics of the Scrotum drain to?
Super๏ฌcial Inguinal Nodes
Where do the Testes form?
Developmentally the Testes form High up on the Posterior Abdominal Wall and are Retro - Peritoneal.
Which Blood Vessels supply the Testes?
Testicular Arteries
Where do the Testicular Arteries arise?
Arise from the Abdominal Aorta
At which Vertebreal Level do the Testicular Arteries arise?
L2
Describe the Venous Drainage of the Testes?
Pampiniform Plexus:
The Testicular Veins emerge from the Testes and the Epididymis as this Venous Network.
What does the Paminiform Plexus become?
This becomes reduced to a Single Vein as it ascends through the Inguinal Canal.
What does each Testicular Vein drain into?
Right Testicular Vein drains into the Inferior Vena Cava
Left Testicular Vein drains into the Left Renal Vein.
What is the Clinical Signi๏ฌcance of Left Venous drainage?
- Left Testicular Vein goes all the way up to the Left Renal Vein before it empties.
- The Left Testicular Vein meets the Renal Vein at a 90 degree angle.
- So, there is more Gravity working on the column of Blood in this Vein.
- This can create a backlog of Pressure.
- Resulting in a higher tendency for the Left Testicle to develop Varicocele,
Where do the Lymphatics of the Testes drain to?
Lumbar Lymph Nodes
Paraortic Lymph Nodes
How can Lymphatics facilitate Cancer?
Cancers can Metastasise to other Organs through their shared Lymphatic Drainage.
Cancer of Paired Organs Metastasises to other Paired Organs.
What is a Variocele?
Swelling caused by Dilated or Enlarged Veins within the Testicle.
What are the Clinical Signs of a Variocele?
Visibly Enlarged/Twisted Veins in the Scrotum
Often described as looking like a Bag of Worms.
What is a Hydrocele?
Swelling caused by Fluid around the Testicle.
Clear Serous Fluid within the Tunica Vaginalis
What are the Clinical Signs of a Hydrocele?
Transilluminates if you shine a torch on it.
Where do the Testes develop before Birth?
In the Abdomen.
How do the Testes reach the Scrotum?
- The Testes descend on the Posterior Abdominal Wall to the Deep Inguinal Ring.
- Then they enter the nascent version of the Spermatic Cord.
- They Traverse down the Inguinal Canal to enter the Scrotum.
What do the Testes acquire as they Descend to the Scrotum?
The Testes and Spermatic Cord acquire a covering,
From all but one of the components of the Anterior Abdominal Wall.
Which of the components of the Anterior Abdominal Wall,
cover the Testes?
- External Oblique Muscle
- Internal Oblique Muscle
- Transversalis Fascia
Which of the components of the Anterior Abdominal Wall,
DO NOT cover the Testes?
Transverse Abdominis Muscle
What is the Gubernaculum?
A Fibrous Cord that connects the Foetal Testes with the bottom of the Scrotum.
What structure pulls the Testes down to the Scrotum and How?
Gubernaculum:
- By failing to elongate in proportion to the rest of the Foetus causes the Descent of the Testes.
- Connects to the Inferior Pole of the Testes.
At what stage of Development do the Testes reach the Scrotum?
Testes reach the scrotum at 32 - 33 Weeks.
What go wrong with the Descent of the Testes?
The Descent can be arrested, at any stage.
What is Cryptorchidism?
Condition in which one or both Testicles fail to move from the Abdomen
Down into the Scrotum.
What risk is increased with Cryptorchidism?
Boys who have had Cryptorchidism that was not corrected in early Childhood,
Are at increased risk for developing Cancer of the Testicles.
What is the Tunica Albuginea?
Fibrous envelope of the Corpora Cavernosa.
What is formed by the Tunica Albuginea?
Mediastinum Testis:
- Tunica Albuginea protrudes into the Posterior Border of the Testis,
- Forming a Longitudinal Ridge called the Mediastinum Testis.
How is the Testis divided?
The Testis is divided into 200 - 300 Lobules by Fibrous Strands,
Radiating from the Mediastinum Testis to the Tunica Albuginea.
What does each Lobule in the Testis contain?
Each of the Lobules contain 1 - 4 Highly Convoluted Seminiferous Tubules.
What are the Seminiferous Tubules?
Tightly Coiled Tubules found in the Testis.
Make up 90% of the Testis.
They are the site of Spermatogenesis
What is the Total Length of all the Seminiferous Tubules?
500m Total Length
List the structures that the Sperm pass through:
- Seminiferous Tubules (Production of Sperm)
- Rectus Tubules
- Efferent Ductules
- Epididymus (Maturation/Storage of Sperm)
How many Sperm are Produced per day?
300 Million on Average produced per day.
Only 120 Million are viable.
What is the Rete Testis?
Network of Tubules carrying Sperm from Seminiferous Tubules to the Efferent Ducts
A collection point for the Sperm before they go to the Epididymis.
How does the Sperm reach the Epididymus from the Rete Testis?
15 - 20 E๏ฌerent Ductules pass Sperm from the Rete Testis into the Epididymis
What is the Epididymus?
The Epididymis is a Highly Coiled Tube (6 - 7m Long).
Where is the Epididymus located?
Situated Postero - Lateral (back and to the side),
To the Upper Part of the Testis.
What are the 3 Divisions of the Epididymus?
- Head
- Body
- Tail
How is the Epididymus connected to the Testis?
The Head of the Epididymus is attached to the Upper Pole of the Testis,
By the Vasa Efferentia.
What are the Vasa Efferentia?
Several Highly Convoluted Tubules that lead from the Rete Testis to the Vas Deferens,
And form the Head of the Epididymis.
What is the Ductus/Vas Deferens?
Tiny Muscular Tube that carries Sperm from the Epididymis to the Ejaculatory Duct.
Which part of the Epididymus does the Ductus/Vas Deferens arise?
Ductus/Vas Deferens lies on Medial Side of Epididymis.
It arises from the Tail of the Epididymus.
What structure do the Epididymis and Vas Deferens arise from?
Mesonephric/Wolffian Duct
What is a Vasectomy?
Surgical procedure for male sterilization or permanent contraception
How is a Vasectomy perfomed?
Male Vas Deferens are Cut and Tied or Sealed,
So as to prevent Sperm from entering into the Urethra and thereby prevent Fertilization
What is Testicular Torsion?
Testicular Torsion occurs when a Testicle Rotates,
Twisting the Spermatic Cord that brings Blood to the Scrotum.
Why is Testicular Tostion a medical emergency?
The reduced Blood Flow causes sudden and often Severe Pain and Swelling.
This is a Medical Emergency if not fixed within 6 Hours.
What is Epididymo - Orchitis?
Inflammation of the Epididymis and Testes.
What can be the consequences of Epididymo - Orchitis?
- Testicular Atrophy:
- Orchitis can eventually cause the affected Testicle to shrink.
- Scrotal Abscess:
- The Infected Tissue fills with Pus.
- Infertility:
- Occasionally, Orchitis can cause Infertility,
- Or inadequate Testosterone production (Hypogonadism).
How can the incidence of Epididymo - Orchitis be reduced?
Antibiotics
Describe the passage of the Ductus/Vas Deferens?
- The Ductus/Vas Deferens is the continuation of the Tail of the Epididymis.
- It runs in the Spermatic Cord.
- Terminating into a Sacculated Structure called the Ampulla of the Ductus.
What structures does the Ductus/Vas Deferens pass through
when it is within the Spermatic Cord?
- Scrotum
- Inguinal Canal
- Into the Abdominal Cavity through the Deep Inguinal Ring, where it is Extra - Peritoneal.
What does the Ampulla of the Ductus merge onto?
The Ampulla attenuates at the base of the Prostate,
And merges with the Seminal Vesicle Duct to form the Ejaculatory Duct.
Opening into Prostatic Part of Urethra.
Describe the relation of the Ductus Deferens to the Iliac Vessels?
Crosses External Iliac Vessels to reach Lateral Wall of Lesser Pelvis.
Medial to Iliac Vessels at the front.
Describe the relation of the Ductus Deferens to the Ureters?
Pass Superior to Ureters to reach Post - Lateral Angle of Bladder.
Medial to Ureter at the back.
Describe the relation of the Seminal Vesicles and Prostate?
Lies Superior to Seminal Vesicles and bends Infero - Medially.
Medial to the Seminal Vesicles.
Superior to the Prostate.