Testis Flashcards
(25 cards)
Testis
Primary male sex organ
Function
Mixed gland:
1. Endocrine: secretes testosterone
2. Exocrine: secretes sperms
Site
- 2 testes are found in scrotum
- One on each side of median septum
- Suspended by spermatic cords which are attached to their posterior aspects
- Left testis level is slightly lower than that of right one
Shape
Oval
Size
- 5cm long
- 2.5 cm thick
- 2.5 cm anteroposterior diameter
Weight
10-15 gm
Surfaces
Medial and lateral
Borders
- Anterior border: convex, smooth, and covered with tunica vaginalis (serous sac)
- Posterior border: straight and partially covered with tunica vaginalis
- Posterior border is related to:
- epididymis: lateral, partially separated from testis by epididymis sinus
- vas deferens: medial
3 special direct coverings
- Tunica vaginalis
- Tunica albuginea
- Tunica vasculosa
Tunica vaginalis
- Outer covering representing persistent lower part of processus vaginalis
- Testis invaginates it from behind and it has two layers:
- visceral layer: covers testis except its posterior border
- lines scrotum
Tunica vaginalis cavity
Contains serous fluid capillary film between the 2 layers
Tunica vaginalis epididymis sinus
- Lateral recess found between testis and epididymis
- Tunica vaginalis upper end is connected to peritoneum by fibrous band processus vaginalis vestigue (processus vaginalis obliterated proximal part)
Applied anatomy
- Accumulation of clean serous fluid (hydrocele), blood (hematocele), and lymph (chylocele) in tunica vaginalis
- Failure of processus vaginalis obliteration results in congenital oblique Inguinal hernia or congenital hydrocele
Tunica albuginea
- Dense white fibrous layer
- Covers testis completely
- Lies deep to tunica vaginalis visceral layer
- Its posterior part is thickened forming testis mediastinum which sends septa inside testis dividing it into 200-300 lobules
Tunica vasculosa
Innermost vascular coat lining testicular lobules
3 coverings of spermatic cord
Extends downwards to surround testis
1. Internal spermatic fascia
2. Cremasteric muscle and fascia
3. External spermatic fascia
3 cutaneous and subcutaneous layers of scrotum
- Skin
- Dartos muscle
- Superficial fascia membranous layer
Atrial supply
Testicular artery
Venous drainage
Pampiniform venous plexus
Lymph drainage
By lymphatics running along testicular vessels to para-aortic lymph nodes
Testicular artery
Branch from abdominal aorta at level of L3 vertebra upper border
1. Descends in front of ureter and Psoas major muscle
2. Reaches deep Inguinal ring
3. Descends down to testis as on of spermatic cord constituents
Pampiniform venous plexus
- Collects its blood into 4-8 veins at superficial Inguinal ring which unite into 2 venae commitantes at deep Inguinal ring
- These 2 veins unite forming one testicular vein which drains obliquely into IVC on right side and at right angle into left renal vein on left side
Applied anatomy: Varicocele
Condition in which Pampiniform venous plexus become dilated, elongated, and tortuous
Why is Varicocele more common on left side?
- Left testicular vein is longer than the right
- Left testicular vein enters left renal vein at right angle
- Left testicular vein is compressed by heavy pelvic colon