Scrotum

what is the gold standard imaging modality for scrotum?

high frequency ultrasound (as well as biliary tree)

testes

are symmetric, oval-shaped glands residing in the scrotum.

testes size

in adults 3-5cm in length, 2-4cm in width, and 3cm AP. each teste is divided into more than 250-400 conical lobules containing the seminiferous tubules.

lobules in testes

each teste is divided into more than 250-400 conical lobules containing the seminiferous tubules. these tubules converge at the apex of each lobule and anastomose to for the rete testis in the mediastinum

Rete testis drains

into the head of the epididymis through the efferent ductules

sonographic appearance of the testes

(homogeneous) Smooth, medium gray structures with fine echo texture

Epididymis

is a 6-7cm tubular structure beginning superiorly and then coursing posterolateral to the testis. it is divided into the head, body, and tail.

epididymis head

Globus major. is the largest portion of the epididymis, measuring 6-15. it is located to the upper pole of the testis. it contains 10-15 efferent ductules from the rete testis, which converge to form a single duct in the body and tail.

ductus epididymis

Contains 10 to 15 efferent ductules from rete testis, which converge to form single duct in body and tail.->It becomes vas deferens and continues in spermatic cord.

Appendix epididymis

from Wollfian duct is a small protuberance from the head of the epididymis

sonographic appearance of epididymis

isoechoic or hypoechoic compared with the testis, although the echotexture is coarser. After vasectomy becomes even more course

Appendix testis

a remnant of the Mullerian duct seen as a small, ovoid structure located on the superior aspect of the testicle or beneath the head of the epididymis. Torsion of this appendage can occur in boys aged 7-12 yo resulting in a "blue dot" sign

Blue Dot sign

may be visible as a hard, tender nodule may be palpable on the upper pole of the testicle and a blue discoloration(bruise). the appearance of a torsed testicular appendage that can be observed as a blue dot just under the skin surface

tunica albuginea

dense fibrous connective tissue that surrounds the testes. The posterior aspect reflects into the testis to form a vertical septum know as the mediastinum

mediastinum

is often seen on ultrasound as a bright hyperechoic line coursing superior to inferior within the testis. Formed from tunica albuginea at mediastinum. Mediastinum supports vessels and ducts coursing within testis.

tunica vaginalis

lines the inner walls of the scrotum, covering each testis and epididymis. it consists of a parietal and visceral layers. Parietal on contact with the scrotal wall and the visceral in contact with the organs. A small bare area is posterior. the space between layers of the is where hydroceles form. it is normal to see a small amount of fluid in this space but not a lot.

Bare are of the tunica vaginalis

A small bare area is posterior. At this site the testicle is against the scrotal wall, preventing torsion. Blood vessels, lymphatics, and spermatic ducts travel through this area

dartos muscle

is a layer of muscle beneath the scrotal skin that divides the scrotum into two chambers. the division of the chambers is called the scrotal raphe

Vas deferens

is a continuation of the ductus epididymis. it dilates at the terminal portion near the seminal vesicles. this portion is termed the ampulla of the deferens.

ejaculatory duct

the vas deferens joins the duct of the seminal vesicles to form the duct, which in turn, empties into the urethra.

Verumontanum

junction of the ejaculatory ducts with the urethra

spermatic cord

vas deferens, testicular arteries, venous pampiniform plexus, lymphatics, autonomic nerves, and fibers of the cremaster form the cord. The cord extends from the scrotum through the inguinal canal and internal inguinal rings to the pelvis. the spermatic cord suspends the testis in the scrotum

testicular arteries

the right and left arise from the abdominal aorta, just below the level of the renal arteries. then they course along the posterior surface of each testis and pierce the tunica albuginea, forming the capsular arteries, which branch over the surface of the testis.

Blood flow of the testis

testicular arteries->capsular->centripetal(toward the center of testicle)-> recurrent rami(Centrifugal-away from center of testicle)-> arterioles-> capillaries

waveform of testicles

low resistance because it needs constant perfusion

Cremasteric artery and deferential artery

accompany the testicular artery within the spermatic cord to supply the extratesticular structures. They also have anastomoses with the testicular artery and may provide some from to the testis (somewhat dual blood supply)

pudendal artery

the scrotal wall is also supplied by

pampiniform plexus

venous drainage of the scrotum occurs through this. exits from the mediastinum testis and courses in the spermatic cord.

testicular veins

the right testicular veins into the IVC and the left joins the left renal vein-> IVC

Beta HCG, AFP, LDH

Lactic Dehydrogenase may be elevated w/ testicular ca

HCG & AFP elevation in conjunction w/ testicular mass suggests testicular ca

AFP elevation = indicator of nonseminomatous tumor. Elevation not found with seminomas

Inguinal orchiectomy is the procedure to determine histological confirmation and present metastatic spread.

Biopsy NOT recommended

Hypoechoic mass in the testicle

just take out the whole testis(orchiectomy) , do not do biopsy

Acute scrotal trauma

if surgery is performed within 72 hours following injury, up to 90% of testes can be saved, but inky 45% can be saved after 72 hours. Hematoma and hydrocele are complications of trauma

Acute scrotal trauma sonographic findings

include focal alterations of the testicular parenchyma pattern, interruption of the tunica albuginea, irregular testicular contour, scrotal wall thickening, and hematocele

hematomas associated with trauma

-may be large and can cause displacement of the testis

-has heterogeneous appearance

-can develop cystic components over time

-may involve the testis or epididymis, or can be contained within the scrotal wall

-will have no flow when using color doppler

Epididymo-orchitis

most common cause of acute scrotal pain in adults. can be independent of each other or in conjunction of each other. it is infection of the epididymis and testis. It most commonly results from the spread of a lower urinary tract infection via the spermatic cord. less common cause include mumps, syphilis, tuberculosis, viruses, trauma, chemical causes, and STIs

Epididymitis sonographic findings

enlarged, hypoechoic. hyperemic flow is confirmed with color Doppler. the normal epididymis shows little flow with color Doppler. The affected side shows significantly more flow than the asymptomatic epididymis. It is important to use the same color Doppler settings when comparing the amount flow between sides

Epididymo-orchitis sonographic findings

causes hyperemic flow with significantly greater number of visible vessels on color Doppler compared with the asymptomatic side. Hyperemic flow is seen in the epididymis and testis when both are involved but is isolated to the epididymis when the testis is normal and vice versa

Testicular abscess

is a common complication of epididymo-orchitis

hematocele

blood located between the visceral and parietal layers of the tunica vaginalis

hydrocele

serous fluid that is between the layers of the tunica vaginalis

pyocele

occurs when puss fills the space between the layers of the tunica vaginalis (can happen is severe cases of epididymo-orchitis)

infarction of testis

can affect the entire testis or may be confined to a focal area

-triangular shaped

- avascular

- Intratesticular (wedge shaped hypoechoic area in periphery like everywhere else)

torsion

Occurs as result of abnormal mobility of testis within scrotum.

-Bell clapper deformity is the most common cause of this condition. torsion results when the testis and epididymis twist on its pedicle, cutting of vascular supply within the spermatic cord. undescended testes are 10 times more likely to be affected by torsion than normal testes. venous flow is affect first. it is a surgical emergency. the sooner it is corrected the better chance of salvage for testes. it is the most common cause of acute scrotal pain in adolescents, peak incidence at age 14

Bell Clapper Deformity

-Bell clapper deformity is the most common cause of this condition. normally the testis and epididymis are surrounded by the tunica vaginalis, except the bare area where they are attached to the posterior scrotal wall. The bell clapper anomaly occurs when the tunica vaginalis completely surrounds the testis epididymis and distal spermatic cord, allowing them to move freely and rotate in the scrotum

sonographic findings of torsion

gray scale findings on ultrasound depend on how much time has passed since the torsion occurred. may be hypoechoic or edematous Presence of flow does not exclude partial torsion, partial or incomplete torsion may be associated with RI> 0.75 or a to and fro(biphasic) waveform

what are most extratesticular tumors

are benign

Spermatoceles

are cystic dilatations of efferent ductules of epididymis:

Always located in epididymal head

Contain proteinaceous fluid and spermatozoa

May be seen more often following vasectomy

Epididymal cysts

super common and can get big

Epididymal cysts are small, clear cysts containing serous fluid located within the epididymis.

Epididymal cysts, spermatoceles, and tunica albuginea cysts are generally asymptomatic but may be palpable.

varicocele

bag of warms- have a relationship with impaired fertility(more common in infertile men)

is an abnormal dilation of the veins of the pampiniform plexus(located within the spermatic cord). is usually caused by incompetent venous valves withing the spermatic cord- primary- most common on left. this is probably die to the mechanics pertaining to the left spermatic vein and the left renal vein.

secondary are caused by increased pressure on the spermatic vein, this may be the result of hydronephrosis, an abdominal mass, or liver cirrhosis.

varicocele sonographic findings

show numerous tubes of varying sizes with the spermatic cord near the epididymal head. the tubes may contain echoes that move with real time imaging. this represents slow venous flow. measure > 2 mm. they tend to increase in diameter in response to the Valsalva maneuver

Adenamatoid Tumor

Most common extratesticular tumor

Usually involves the epididymis

Leydig cell tumors

Affects boys 5-10 yrs and men 30-60 yrs

Always benign in children, malignant variants reported in adults

Commonly found in males, have been reported in ovaries

-Ovarian Leydig cell tumors are usually malignant

Tumor produces testosterone resulting in precocious puberty

-Ovarian Leydig cell tumors are usually malignant and may secrete estrogen (feminizing)

May be pure non-germ cell or mixed

Pure = normal AFP, HCG, & LDH levels

precocious puberty

the very early onset and rapid progression of puberty

most common cause of correctable infertility in men

varicocele

scrotal hernia

occur when bowel, omentum, or other structures herniate into the scrotum. the bowel is the most commonly herniated structure, followed by omentum

scrotal hernia sonographic findings

peristalsis of the bowel, seen on real-time imaging, confirms the diagnosis of a scrotal hernia. Unfortunately peristalsis may not always be visible

Leydig cell tumors in children

benign

Leydig cell tumors in adults

malignant

sperm granuloma ->

histoplasmosis

Sperm Granuloma

reaction to inflammation/inflammatory diseases. They are most frequently seen in patients with a history of vasectomy

tubular ectasia of the rete testis

the rete testis is located at the hilum of the testis, where the mediastinum resides. This is an uncommon, benign conditions. It is more commonly seen in patients 45 and older

tubular ectasia of the rete testis sonographic findings

appears as prominent hypoechoic(anechoic) channels near the echogenic mediastinum testis.

Epidermoid Cysts

Benign germ cell cysts

Filled w/ cheesy white keratin.

Hypoechoic, echogenic capsule, onion ring pattern formed by multiple layers of keratin

"Bow tie" central echogenic pattern

Epidermoid Cysts sonographic findings

Filled w/ cheesy white keratin.

Hypoechoic, echogenic capsule, onion ring pattern formed by multiple layers of keratin

"Bow tie" central echogenic pattern

Microlithiasis

uncommon condition characterized by tiny calcifications within the testis. these microcalcification are <3mm

scrotal pearls

Calcifications that may be located within the testicle or between the layers of the tunica vaginalis.

malignant testicular masses

testicular cancer is not common, but it is the most common malignancy in men between 15-35 years old. Testicular cancer is one of the most curable forms of cancer. It is more common in white men. occurs more frequently between ages 20-34. Undescended testes are 2.5-8 time more likely to develop cancer.

symptoms of men with malignant testicular masses

most patients have no other symptoms except a painless lump, testicular enlargement, or vague discomfort in the scrotum.

sperm granuloma is also called?

microlithiasis or microcalcifications

intratesticular masses are?

more likely to be malignant

what is the most common germ cell tumor

seminoma and more curable form

in general testicular tumors are divided into?

•Germ cell tumors (malignant)

• Non-germ cell tumors (benign)

germ cell tumors are associated with

elevated alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG) levels. approximately 95% of all testicular tumors are of germ cell type and are highly malignant

Most common type of testicular cancer in infants

yolk sac and are associated with elevated AFP

order of germ cell tumors from more common to least common

seminoma->embryonal cell (yolk sac)-> teratocarcinomas. the more common the less dangerous/aggressive

when do embryonal and yolk sac tumors tend to occur?

in infants/younger patients

sonographic findings of seminomas

Well-defined, hypoechoic, solid, no calcifications or tunica invasion

metastasis of scrotum/testis

metastasis of testicle is rare, normally occurring later in life. The primary tumor may originate from the prostate or kidneys; less common sites include lungs, pancreas, bladder, colon, thyroid, and melanoma

Lymphoma of testes

is the most common bilateral secondary testicular neoplasm affecting men older than 60

leukemia of testes

is the second most common bilateral secondary testicular neoplasm affecting men

Cryptorchidism

undescended testicles. this is more common in premature babies. this testicle has an increased risk of cancer. increased temp causes infertility. torsion is more common as well

orchiopexy

surgical treatment of an undescended testicle by freeing it and implanting it into the scrotum. this does not reduce risk of cancer

Cryptorchidism ectopic locations

during fetal growth, the testis first appear in the retroperitoneum near the kidneys. they descend into the scrotum from the inguinal canal shortly before birth or soon after. because of this the undescended testis may be in the abdomen, inguinal canal, or other ectopic locations. in most cases(80%) the testis is found in the inguinal canal and is usually palpable.

Cryptorchidism sonographic findings

the undescended testis is smaller and less echogenic than the normal testis. it is usually oval with a homogenous texture. rarely the mediastinum is seen

testicular ectopia

somewhat superior to the inguinal canal. the most common site is the superficial inguinal pouch. other sites include the peritoneum, femoral canal, suprapubic area, penis, diaphragm, and other scrotal compartment

anorchia

absence of one or both testicles

bilateral is found in only 0.6-1.0% of patients with a nonpalpable testis. patients have a male XY genotype

Polyorchidism (testicular duplication)

very uncommon condition. more common on the left side (75%). is usually found in the scrotum but has also been found in the inguinal canal or retroperitoneum. the incidence of malignancy, cryptorchidism, inguinal hernia, and torsion is increased with this condition.

Anatomy of the Penis

The penis is covered with skin, and subsequently a dense fibrous tissue termed Buck fascia.

The inner penis is comprised of three cylindrical tissue components: a single corpus spongiosum (situated ventrally) and paired corpus cavernosa (situated dorsally)

The urethra is housed within the corpus spongiosum,

Tunica albugenia surrounds the corpus cavernosa and partially covers the corpus spongiosum.

All three corpura are covered by Buck fascia

which erectile tissue houses the urethra

corpus spongiosum

the inner penis is comprised of?

The inner penis is comprised of three cylindrical tissue components: a single corpus spongiosum (situated ventrally) and paired corpus cavernosa (situated dorsally)

Tunica albugenia

surrounds the corpus cavernosa and partially covers the corpus spongiosum.

Buck fascia

a dense fibrous tissue. All three corpura are covered in this

how many corpus spongiosum

singular, ventrally- houses the urethra

how many corpus cavernosa

2, dorsally(laterally)

Sonography of the Penis

In the anatomical position, the penis is considered to be erect and pointing upward

When scanning, the Corpus Spongiosum is directly under the transducer

Sonography of the Penis-Dorsal

posterior side - touching belly

Sonography of the Penis-Ventral

anterior side - scanning surface

Priapism

n- erection lasting > 4 hrs

-Usually painful

Ischemic Priapism

blood gets trapped in the erection chambers- no fresh 02 rich blood->necrosis

-Assoc w/ sickle cell disease, leukemia, malaria

Drugs that may cause priapism

-ED meds

-Depression & mental illness meds

Marijuana & Cocaine

Peyronie's disease

plaque that forms inside the penis resulting in bent, rather than straight erection- caused by scar/ fibrous tissue

It's believed that the scar tissue forms as a result of trauma which causes bleeding inside the penis

US used to localize the plaque buildup on the anterior or posterior aspect of the penis