Urogenital triangle in male

Dr Rania Gabr

UROGENITAL TRIANGLE IN MALE

OBJECTIVES1. Describe the boundaries, division & contents of urogenital triangle in male.2. Recite the parts of the male external genital organs.3. Define the scrotum.4.Describe the normal site & shape of the scrotum.5. Discuss the layers and the contents of the scrotum.6. Define the blood supply of the scrotum.

7. Define the parts of the penis.8. Discuss the sectional anatomical structure of the penis.9. Mention the vascular and nerve supply of the penis.10. Discuss its lymphatic drainage

PERINEUM• The cavity of the pelvis is divided by the pelvic

diaphragm into :

• 1- the main pelvic cavity above and

• 2- the perineum below,

• When the thighs are abducted, the perineum is diamond shaped and is bounded:

• anteriorly by the symphysis pubis,

• posteriorly by the tip of the coccyx, and

• laterally by the ischial tuberosities

PERINEUM

• Two Triangles• Anal triangle (posterior) contains the anus• Urogenital triangle (anterior) contains the

root of the scrotum and penis in males or the external genitalia in females

• The perineal membrane stretches between the two sides of the pubic arch and covers the anterior part of the outlet

TRIANGLES

PERINEAL BODY• An irregular mass of variable size and consistency, located at

midpoint of the line between the ischial tuberosities• Forms the central point of the perineum• Lies in the subcutaneous tissue, posterior to vestibule and anterior

to the anal canal & anus, blends anteriorly with the perineal membrane

Function:It serves as a point of attachment for the following muscles: external anal sphincter, bulbospongiosus muscle, and superficial transverse perineal muscles.• Plays an important role in

visceral support especially in female

PERINEAL BODY

The urogenital diaphragm is a triangular musculofascial diaphragm situated in the anterior part of the perineum.It is formed by the sphincter urethrae muscle & deep transverse perineal muscles, which are enclosed between a superior and an inferior layers of fascia of the urogenital diaphragm. The inferior layer of fascia is often referred to as the perineal membrane.

Urogenital Diaphragm

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Contents of the Male Urogenital TrianglePenis Location and DescriptionThe penis has a root, & a body

RootRoot is made up of 3 erectile tissue called the bulb of the penis. (paired corpora cavernosa dorsally & single corpora spongiosum ventrally) & the right and left crura of the penis.

BulbThe bulb is attached to the undersurface of the urogenital diaphragm, traversed by the urethra and is covered on its outer surface by the bulbospongiosus muscles

The bulb is continued forward into the body of the penis and forms the corpus spongiosum.

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CruraEach crus is attached to the side of the pubic arch and is covered on its outer surface by the ischiocavernosus muscle. The two crura converge anteriorly and come to lie side by side in the dorsal part of the body of the penis, forming the corpora cavernosa.

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PENIS Copulatory & Excretory

organ. Excretory: Penile urethra: Carries

urine & sperm. Copulatory: Has (3) cylindrical

masses or erectile tissue Two Corpora

Cavernosa One Corpus

Spongiosum

CCCS

Corpora Cavernosa

Paired Right & leftSuperior masses of(Primary erectile tissue).Provide the majority of rigidity & length of penisTheir Posterior Expansions: form Crura (anchor” tissue) against pelvic bone

Corpus Spongiosum

The Inferior mass(A Secondary erectile tissue)

Traversed by the Penile urethraIts Anterior expansion: forms the GlansPrepuce : Fold of skin covering glansIts Posterior expansion: forms Bulb of penis

Blood SupplyArteriesThe corpora cavernosa are supplied by the deep arteries of the penis the corpus spongiosum is supplied by the artery of the bulb. In addition, there is the dorsal artery of the penis. (branches of internal pudendal artery)

VeinsThe veins drain into the deep dorsal veins to the internal pudendal veins.

Lymph DrainageSuperficial inguinal nodes & internal iliac nodes.

Nerve SupplyPudendal nerve & the pelvic plexuses

COMPONENTS OF MALE REPRODUCTIVE SYSTEM

I- Primary Sex Organ: Testis.

II- Reproductive Tract: Epididymis. Vas Deferens. Spermatic cord.

III- Accessory Sex Glands: Seminal vesicles. Prostate gland. Bulbourethral glands.

IV- External genitalia: Penis

SCROTUM

The scrotum is a cutaneous sac consisting of two layers: heavily pigmented skin and closely related dartos fascia

It is divided into two compartments which are distinguished externally by a middle ridge called the raphe. Internally, the raphe connects to a muscular partition, the septum, which serves to divide the scrotum into its two areas

The Left scrotum is lower than the right.

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Contents:One testis and one epidydimis in each compartement

Functions: Houses & Protects the testis Regulates testicular temperature It has thin skin with sparse hairs and sweat glands. The Dartos muscle lies within the superficial fascia.

• The arterial supply of the scrotum :1- Posterior scrotal branches of the perineal artery, a branch of the internal pudendal artery.

2- Anterior scrotal branches of the deep external pudendal artery, a branch of the femoral artery.

3- Cremasteric artery, a branch of the inferior epigastric artery.

• Scrotal veins accompany the arteries

• Lymphatic vessels of the scrotum drain into the superficial inguinal lymph nodes

• The nerves of the scrotum include the:• Genital branch of the genitofemoral nerve (L1, L2) supplying

the anterolateral surface.• Anterior scrotal nerves, branches of the ilioinguinal nerve (L1)

supplying the anterior surface.• Posterior scrotal nerves, branches of the perineal branch of

the pudendal nerve (S2- S4) supplying the posterior surface.• Perineal branches of the posterior femoral cutaneous nerve

(S2, S3) supplying the inferior surface.

TESTIS

• Paired almond-shape gonads that are suspended in the scrotum by the spermatic cord

• 4 - 5 cm long

• Weigh (10.5 – 14) g Functions:

Spermatogenesis. Hormone production (Androgens-

testosterone).

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-It develops in the abdomen; descends into the scrotum before birth;

-It is made up of tightly coiled tubes (SEMINIFEROUS TUBULES) where sperms are formed;

-scattered between tubules are the LEYDIG CELLS (produce testosterone and other androgens).

(Leydig cells)

TESTIS

COVERINGS OF THE TESTIS• Tunica Vaginalis:• Peritoneal covering,

formed of parietal and visceral layers.

• It surrounds testis & epididymis.

• It allows free movement of testis inside scrotum.

• Tunica albugenia• It is a whitish fibrous

capsuleTV

Internal Structure of Testis

Fibrous septae extend from the capsule, divide the testis into a (200-300) lobules.

Each lobule contains, (1-3) seminiferous tubules.

Seminiferous Tubules:They are the site of the spermatogenesis.They form the bulk of testicular tissue.

Rete testis: (a network of tubules)It is the Site of merging of the Seminiferous tubules.

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BLOOD SUPPLY OF TESTIS

Testicular artery:

It is a direct branch from the abdominal aorta.

Venous drainage : (Pampiniform plexus of veins. Approximately a dozen veins

which forms a network in the spermatic cord.

• They become larger, converge as it approached the inguinal canal and form the Testicular vein.

Testicular Artery

Right Vein drains into IVC.Left Vein drains into Left Renal Vein.

Testicular Lymphatics:Follow arteries, veins end in Lumbar (par aortic) nodes From scrotum, penis, prepuce: Terminate in Superficial Inguinal nodes

EpididymisA Single coiled tubule

6 M long Located on the posterior & superior margins of the testis. It is divided into:Head, Body and Tail.

The Head receives efferent ductules from testis.The Tail is continuous with Vas Deferens

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Functions:• 1. Secretes/absorbs the nourishing

fluid.• 2. Recycles damaged spermatozoa.• 3. Stores spermatozoa Up to 2 weeks

to allow for maturation.• It is the site where sperms become

motile and gain the ability to fertilize.

VAS DEFERENS

A Muscular tube 45 cm long. Carries sperms from the

Epididymis to pelvic cavity.• Passes through the inguinal

canal • It crosses the ureter• Its terminal part is dilated to

form the Ampulla of the vas It joins the urethra in the

prostate

Thank you