Chapter 2 - Male External Genitalia Flashcards
1
Q
Root of penis
A
- situated in superficial perineal pouch
- has 3 masses of erectile tissue i.e., 2 crura, 1 bulb
- Crus attached to pubic arch
- crus covered by ischiocavernosus
- bulb attached to perineal membrane b/w crura
- bulb covered by bulbospongiosus
- bulb pierced by urethra which shows intrabulbar fossa
2
Q
Body of penis
A
- continuous with root
- 3 masses of erectile tissue i.e., 2 corpora cavernosa, 1 corpus spongiosum
- C. cavernosa are forward continuations of crura
- C.C terminate near glans penis
- Covered by tunica albuginea
- C. spongiosum is forward continuation of bulb
- C.S forms glans penis (conical enlargement)
- C.S traversed by urethra
3
Q
Glans penis
A
- Base of glans has projecting margin - corona glandis
- Within glans, urethra shows dilatation called navicular fossa
- Skin at neck is folded to form prepuce/foreskin
- Prepuce can be retracted to expose glans
- Median fold of skin on undersurface - frenulum
- Potential space b/w glans and prepuce - preputial sac
- Neck has sebaceous glands which secrete smegma that collects in preputial sac
4
Q
Superficial fascia of penis
A
- loosely arranged areolar tissue devoid of fat
- continuous with membranous layer of superficial fascia of abdomen above
- contans superficial dorsal vein of penis
5
Q
Deep fascia of penis
A
- Buck’s fascia
- Surrounds all 3 layers of erectile tissue
- Does not extend to glans
- Deep to it, there are deep dorsal veins, dorsal A, dorsal N
- continuous with Dartos and fascia of urinogenital triangle
6
Q
Supports of body of penis
A
- Fundiform ligament: extends down from linea alba and splits to enclose penis
- Suspensory ligament: deep to fundiform ligament. Extends from pubic symphysis and blends with fascia on each side of penis.
7
Q
Arteries of penis
A
A) 3 branches of internal pudendal A
- Deep A of penis: runs in C. cavernosum and breaks up into helicine A
- Dorsal A of penis: supplies glans, distal C. spongiosum, prepuce, frenulum
- A of bulb of penis: supplies bulb and proximal C. spongiosum
B) Femoral A gives superficial external pudendal A - supplies skin and fascia of penis
8
Q
Veins of penis
A
- Superficial dorsal V - drains prepuce, skin - empties into external pudendal V
- Deep dorsal V
- deep to Buck’s fascia
- drains glans, C. cavernosa
- passes deep to suspensory ligament
- divides into right, left branches
- connects with internal pudendal V
- enters prostatic plexus
9
Q
Nerve supply of penis
A
SENSORY
- Dorsal N of penis
- Ilioinguinal N
- Root by perineal branch of pudendal N
AUTONOMIC
- Pelvic, prostatic plexus
- Sympathetic - S2-S4
- Pudendal N
10
Q
Lymphatic drainage of penis
A
Glans - deep inguinal nodes/ glands of Cloquet
Rest - superficial inguinal nodes
11
Q
External features of scrotum
A
- cutaneous bag containing testes, epididymis and lower parts of spermatic cord
1. Externally divided into right and left by raphae which continues on undersurface and along perineum
2. Left half hangs lower than right due to > length of left spermatic cord
3. When cold, it is short and corrugated
4. When warm, it is elongated and flaccid
5. Contraction and relaxation is due to dartos muscle
12
Q
Layers of scrotum
A
- Skin
- Dartos muscle replaces superficial fascia
- External spermatic fascia from ext. oblique M
- Cremasteric fascia from int. oblique muscle
- Internal spermatic fascia from fascia transversalis
13
Q
Blood supply of scrotum
A
- Superficial external pudendal
- Deep external pudendal
- Scrotal branches of internal pudendal
- Cremasteric branch of inferior epigastric
14
Q
Nerve supply of scrotum
A
Ant 1/3 - L1 segment through ilioinguinal, genital branch of genitofemoral N
Post 2/3 - S3 segment through posterior scrotal branches of pudendal, perineal branch of posterior cutaneous N of thigh
Dartos M - genital branch of genitofemoral N
15
Q
External features of testis
A
- homologous to ovary
- lies obliquely
- 2 poles, 2 borders, 2 surfaces
