Scrotum- Part 1

Question 1

Testicular Development

Answer 1

Testicles arise in fetal abdomen near kidneys. 4th month descend to level of bladder & remain there until 7th month. They descend through inguinal canal to scrotum after 7th month. Descent is controlled by hormones.

Question 2

Process vaginalis

Answer 2

Evagination of peritoneum travels through inguinal canal from abdomen into scrotum

Question 3

Scrotum

Answer 3

Pouch of skin that is continuous with abdomen. Suspended from base of male pelvis btw perineum & penis. Derived from labioscrotal folds.
Median Raphe: point of fusion of twin sacs

Question 4

Scrotum Purpose & Contents

Answer 4

Protective casing. Maintain testicular temp at ~2 deg C below intrabdominal temp.
Contents: testicles, epididymis, proximal part of vas deferens

Question 5

Testicles (testes)

Answer 5

Male gonads. Oval shaped symmetric. US: appear as smooth medium gray structures with fine echo texture.
Each testis: divided into ~250-400 lobules that contain SEMINIFEROUS TUBULES. Tubules join to from 20-30 larger ducts, known as the tubuli recti.

Question 6

Testicle Size

Answer 6

Normally measure 3-5 cm in length. AP: 3cm. Width 2-4 cm. size & weight decrease with age.

Question 7

Jobs of the scrotum:

Answer 7

Produces sperm & testosterone. 95% of testosterone is secreted by Leydig cells in the testicles.
Endocrine & exocrine functions: testosterone - endocrine

Question 8

Tunica Albuginea

Answer 8

Echogenic, dense fibrous capsule surrounding testes. Covered b tunica vaginalis. Mult septa are formed from tunica Albuginea and coverage at mediastinum testis. Form lobules in the testes.

Question 9

Mediastinum Testis

Answer 9

Posterior portion of tunica Albuginea reflects into the testis forming a vertical septum. Supports the testicular vessels and ducts. Extends into testicles from the epididymis.

Question 10

Tunica Vaginalis

Answer 10

Serous membrane, formed by peritoneum, that partially testicle. Inner visceral layer covers testis, epididymis, lower spermatic cord. Outer parietal layer lines wall of scrotal pouch. Small amount of fluid btw 2 layers is normal. Layers normally not seem on US.

Question 11

Seminiferous Tubules

Answer 11

Contained within the testes. Converge at apex of each lobule and anastamose. Tubuli recti enter mediastinum to form Rete Testis in medistinum testis. Rete testis drains into the head of the epididymis through Efferent Ductules.

Question 12

Epididymis

Answer 12

Single tightly wrapped tube, 6-7cm, begins superiority and courses posterolateral to testis. Composed of head body tail and appendix. Aids in sperm maturing as well as concentrates, stores and transports sperm.

Question 13

Epididymal Head

Answer 13

AKA: globus major. Measures 10-12 mm diameter. Superior to upper pole of the testis. Larger portion of epididymis. Formed 10-15 efferent Ductules from Rete testis joining together

Question 14

Epididymal Body

Answer 14

Bod is smaller then head. Posterolateral margin of testicle.

Question 15

Epididymal Tail

Answer 15

AKA: globus minor. Slightly larger then bod. Inferior to testis

Question 16

Appendix Epididymis

Answer 16

Appendix is small protuberance on head. Commonly seen when hydrocele present (excess fluid in scrotum)

Question 17

Seminal Vesicles

Answer 17

Are convoluted pouch like structures that empty into the distal ductus deferens to form ejaculatory ducts. NOT in the scrotum but part of reproductive tract. Paired gland encapsulated by connective tissue. US: appear as low level echoes superior to the prostate.

Question 18

Appendix testis & Appendix Epididymis

Answer 18

Not always seen, but are susceptible to torsion.

Question 19

Scrotal Skin Thickness

Answer 19

Typically 2-8 mm. Thickens in presence of inflammation and other conditions.

Question 20

Mediastinum Testis on US

Answer 20

Sometimes seen as Echogenic band going through the testicle. Echogenic line that runs from superior to inferior pole of testicle. Parallel to epididymis longitudinally.

Question 21

Vas Deferens

Answer 21

Continuation of ductus epididymis. Thicker & less convoluted. Dilates at the terminal end near the seminal vesicles. Part of the spermatic cord

Question 22

Spermatic Cord

Answer 22

Connects the abdomen and scrotum. Suspends the testis in the scrotum.
Functions: arterial supply. Venous drainage. Contains nerves, lymph nodes & vas deferens. Bound by fibrous sheath. Lies directly under skin.

Question 23

Verumontanum

Answer 23

Junction of ejaculatory ducts and urethra

Question 24

Vascular Supply

Answer 24

Blood flow supply from deferential cremasteric & testicular arteries. Testicular a’s descend from aorta to enter spermatic cord. Arise anteriorly just inferior to renal A. Travel through inguinal canal with spermatic cord. Capsular arteries (tunica vasculosa) branch over surface of testis.

Question 25

Venous Drainage

Answer 25

Pampiniform plexus- exits from mediastinum testis into spermatic cord. Converge into 3 vessels: testicular, cremasteric, deferential. Right testicular drains directly into IVC. Left testicular drains into LRV.

Question 26

Sonographic Appearance

Answer 26

Homogeneous texture. Echogenicity increase with age. Sag:3-5 cm AP: 3 cm TRV: 2-4 cm. weight ranges from 12.5-19.0 grams. Normal volume= 15-20 cc

Volume= (length X width X AP)

Question 27

What should be imaged

Answer 27

Spermatic cord should be scanned from inguinal canal to scrotum. Epididymal head body & tail. Head is superior to upper pole of the testicle. Isoechoic to testicle. More coarse than testicle.

Question 28

Hydrocele

Answer 28

Space btw the layers of the tunica vaginalis contains excess serous fluid. MOST COMMON CAUSE OF PAINLESS SWELLING. Simple- anechoic. Reactive Hydroceles- contain echoes in fluid, caused by trauma infection. Epididymis attaches to testicular wall posteriorly, fluid only in anterolateral portion only.

Question 29

Hematocele

Answer 29

Less common then Hydroceles. From surgery trauma diabetes torsion neoplasms. May contain septations. Wall of scrotum becomes thickened. PYOCELES- abscesses that rupture.

Question 30

Cryptorchidism

Answer 30

Normal variant. Testicles fail to descend into scrotum. Can be due to short spermatic cord, fibrosis & adhesions, narrow inguinal canal. Can be found in abdomen, inguinal canal(65%), & external inguinal ring. Can cause infertility or cancer. Kids: orchiopexy. Adults: orchid tommy. Normal testicle is larger & more Echogenic than undescended one.

Question 31

Polyorchidism

Answer 31

Also called supernumary testis- many testes. Can be found anywhere along path. Attach to normal testis b duplicated vas deferens. Function normally within scrotum.

Question 32

Idiopathic Varicoceles

Answer 32

MOST COMMON CORRECTIBLE CAUSE OF INFERTILITY. 98% occur on the left side in ages 15-25. Dilated veins from obstruction of venous return. When patient “bears down” it lights up like a XMas tree.. You know!

Question 33

Secondary Varicoceles

Answer 33

From extreme pressure on the spermatic vein, enlarged liver, abdominal masses or retroperitoneal mass compressing veins. Pt position doesn’t affect. Numerous anechoic structures. Measure more the. 2mm. Follow spermatic cord to inguinal canal. Can be compressed by probe.

Question 34

Microlithiasis

Answer 34

Scattered tiny punctate foci throughout the testicle. May be unilateral or bilateral. Found to have significant association With testicular cancer

Question 35

Hernia

Answer 35

Are from inguinal hernias that slip into the scrotum. 2types: Direct- caused by weakening of the floor. Indirect- when intestines escape into the scrotum. EXCESSIVE STRAINING OR LIFTING HEAVY THINGS COMMON CAUSES. Symptoms: scrotal swelling, palpable firm area within the scrotum, lower abd pain.

Question 36

US of hernias

Answer 36

Scrotal mass with both Echogenic & anechoic mass. PERISTATIC MOTION can be detected.
Hydroceles & hematoceles with fibrous septations may appear like fluid filled bowel loops. Inflamed spermatic cord also mimics hernia.

Question 37

Epididymitis

Answer 37

Inflammation of the epididymis. MOST COMMON CAUSE OF ACUTE SCROTAL PAIN IN ADULTS. Most common cause is UTIinfection spread through spermatic cord. Others: mumps, syphilis, viruses, STDs. Unilateral mostly. May be focal or whole epididymis is involved.

Question 38

US of Epididymitis

Answer 38

Thick enlarged epididymis decreased echoes in affected area. Thickening of scrotal skin. Reactive hydrocele. Doppler shows increased blood flow in the affected area. May be isolated to head or tail.

Question 39

Epididymo-Orchitis

Answer 39

Infection of both epididymis & testicle. Epididymitis spreads to testic,e 20-40% of cases. Testis is enlarged. May have focal abnormality or be entirely affected. Scrotal wall thickening. May lead to abscess formation.

Question 40

Fournier’s Gangrene

Answer 40

Uncommon type of gangrene affecting soft-tissue of genital organs. Stems for. Infection, UTI, urethral injury/stricture, trauma (piercing). TX: debridement of entire scrotum, and occasionally penis as well. Usually requiring major reconstructive surgery with skin grafts

Question 41

Epididymal Cysts

Answer 41

Asymptomatic. Can develop throughout the epididymis

Question 42

Spermatocele

Answer 42

MOST COMMON TYPE OF EPIDIDYMAL CYST. Retention cyst of the small tubes that hold sperm. May cause anterior or inferior displacement of the testicle. Single or mult. No symptoms until symptomatic then surgically corrected. Range from .2-9 cm in size.

Question 43

Tunica Albuginea Cysts

Answer 43

Range from 2-5mm. Present as palpable lumps. Usually Asymptomatic . 50-60 YEAR OLD MALES. Cause is unknown.

Question 44

Torsion

Answer 44

Most common in children & teenage boys, but can happen at any age. Occurs when remnant stalk of tunica vaginalis is twisted causing restrictin/obstruction of blood flow to testicle. Surgical emergency in acute phase. Arterial occlusion followed by ischemia.

Question 45

Testicular Rupture

Answer 45

Must be diagnosed early. Blunt trauma is most common cause. 90%can be saved if surgery is performed within 72 hrs. Treatment: repair or removal. Severe scrotal pain & swelling. Focal areas of altered echogenicity. Contour of testicle is irregular. Color flow can be used to avoid mistaking complex hematoma for rupture.

Question 46

Testicular Hematoma

Answer 46

Focal hematoma. From trauma.. Absence of flow