Ultrasound technique of male pelvis

Question 1

What is a haematocele

Answer 1

Blood filled collection surrounding the testis
Usually associated with trauma
Often isoechoic to the testis, particularly in the acute stage. More frequently they are thick with irregular septa and multilocular

Question 2

What is the definition of microlithiasis?

Answer 2

More than 5 echogenic foci and must be demonstrated in one image
Punctate, non-shadowing, hyperechoic foci within the testis.
Between 1-3mm in diameter
May be scattered throughout or in dense clumps.
Can be associated with an increased risk of testicular cancer.

Question 3

What is a scrotal pearl?

Answer 3

Benign, extratesticular macrocalcification.

Freely mobile between the layers of the tunica vaginalis. Can be palpable.

Question 4

What is a varicocele?

Answer 4

A varicocele is abnormally dilated, tortuous and elongated veins of the pampiniform plexus
2-3mm is the cut off point for a varicocele. Can feel like a bag of worms

Question 5

What is tubular ectasia?

Answer 5

Tubular ectasia of the rete testis often occurs at the mediastinum.
Dilation of the different ductules usually occur secondary to vasectomy or as a result of inflammation or trauma.
Can be congenital

Question 6

Name some transducer and system modifications for scanning testes

Answer 6

• High frequency linear transducer
  
  • Large footprint
  • Focal zone placed appropriately and the field of view provides an overview of an area being imaged but adjusted in size to maximise the area of interest
  • Speckle reduction
  • Compound imaging can remove information that allows the differentiation of cystic from solid masses
  • Colour should be optimised to show low volume, low flow velocity:
    ○ Remove the wall filter
    ○ Decrease pulse repetition frequency
    ○ Increasing Doppler gain, adjusted so that noise is suppressed
    ○ Increasing line density
    ○ Reducing persistence and frame averaging
    ○ Increasing colour write priority
  • Colour control should be set to show low blood flow states
  • High setting assists in identification of small vessels
    Comparisons with the other side can be a good indicator for any issues with colour velocity and texture

Question 7

What are some points of ultrasound technique for scanning the testes?

Answer 7

Pay particular attention to privacy and respect issues
Maintain a professional and courteous attitude
Warm room, warm gel, warm hands
Palpable lesions located
Use care and sensitivity
Patient is asked to be in a supine position and asked gently to hold their penis towards their abdominal wall
Use ample warm gel to cover the testes and remove all air among the scrotal hairs
use gentle pressure so not to push the region of interest outside the scanning plane

Question 8

What is the tunica albuginea?

Answer 8

The testis is enclosed by the tunica albuginea. It is a fibrous capsule which thickens postero-superiorly as it penetrates the testis and is seen as an echogenic triangular or linear echo of varying thickness. This is the mediastinum testis

Question 9

What and where is the tunica vasculosa?

Answer 9

The tunica vasculosa is deep to the tunica albuginea. Contains the capsular artery and veins. Can sometimes be seen as a hypoechoic rim around the testes

Question 10

What can prominent septa do?

Answer 10

Septa radiate from the mediastinum and divide the testis into 250-400 conical lobules. This can cause an irregular, heterogeneous echo pattern

Question 11

What is the tunica vaginalis?

Answer 11

The tunica vaginalis is a membrane with two layers. The visceral layer covers the testis and epididymis. This layer produces secretions.
The parietal layer lines the scrotum and extends into the spermatic cord. This layer contains lymphatics for absorption. A potential space exists between these layers, a small amount of fluid is normal.

Question 12

Describe the sonographic appearance of the epididydmis

Answer 12

Head should be iso or hyperechoic in comparison to the testis. Normally triangular or pyramidal in shape, but becomes rounded with inflammation.
Body is hypoechoic in comparison to testis.
Tail is also hypoechoic and has a variable appearance. It is continuous with the vas deferens which ascends on the medial side of the testis

Question 13

What are some epididymal anatomical variants?

Answer 13

Epididymides that only reach the mid-portion of the testis.
The head of the epididymis is situated at the lower pole of the testis
The whole epididymis is situated superiorly to the testis

Question 14

What is the spermatic cord?

Answer 14

The spermatic cord extends from the deep inguinal ring to the testis. It contains the vas deferens
testicular, deferential and cremasteric arteries
the pampiniform plexus of veins
lymphatic vessels
nerves
ligament of Cloquet (vestige of the processus vaginalis)
It is held together by fatty cellular connective tissue

Question 15

Describe the normal sonographic appearance of the spermatic cord

Answer 15

echogenic structure through which fine hypoechoic linear vessels run. usually <1cm in diameter

Question 16

What is the ultrasound sign of impending infarction?

Answer 16

Reduced or reverse diastole of the intratesticular artery compared to the contralateral side.

Question 17

What should we do if there is no cause for testicular pain found?

Answer 17

Evaluation of the inguinal canal to search for an inguinal hernia that could be compressing the nerves in the canal. another cause of acute testicular pain is a stone at the VUJ on the symptomatic side

Question 18

What is cryptorchidism?

Answer 18

An undescended testis. The testis will be found along the path of descent. Use ultrasound to look for the inguinal canal or the upper scrotal area. Occasionally, the testis will be in the abdomen, so MRI or CT is the imaging modality of choice.

Question 19

What is an ectopic testis

Answer 19

An ectopic testis sits outside the scrotum and normal path of descent. It can be found:
interstitial on the oblique muscle
pubopenile
perineal
in the femoral triangle

Question 20

What is the normal route of descent of the testis?

Answer 20

Normal descent of the testis occurs in the last trimester, usually between 28 and 32 weeks along the inguinal canal.

Question 21

Is arrest of descent uncommon?

Answer 21

Arrest of descent is not uncommon. 3% of full term infants are affected. 1% still remain affected at the end of the first year of life. Right testis is more commonly affected, possibly because it descends later than the left and the processus on the right is more likely to remain patent.
There is an increased risk of cancer in the case of the undescended testis.

Question 22

What is the normal sonographic appearance of the testis?

Answer 22

Testis appears as an oval structure with mixed echoes, predominantly hypoechoic. The mediastinum testis is seen as a linear hyperechoic band and blood flow can be detected on colour.

Question 23

Name some congenital anomalies of the testis

Answer 23

Cryptorchidism
ectopic testis
congenital inguinal hernia
hydrocele
monorchidism
anorchidism
polyorchidism

Question 24

What are the most common congenital anomalies of the epididymis and vas?

Answer 24

Agenesis or hypoplasia (still extremely rare <1%)

Often associated with testicular anomalies

Question 25

When is the presence or absence of the vas most important?

Answer 25

In infertility studies

Question 26

When might a patient be referred to ultrasound to search for a vas?

Answer 26

a non-palpable vas deferens during a vasectomy can result in an ultrasound request to confirm the presence or absence of this structure

Question 27

What is agenesis of the vas deferens commonly associated with?

Answer 27

renal agenesis

essential to examine the renal tract

Question 28

What is the appendix testis?

Answer 28

mesonephric remnant and is a small rounded structure of fibrous tissue situated anteriorly at the junction of the testis and head of epididymis. It can have internal calcifications. this can undergo torsion and become detached

Question 29

what is the appendix epididymis?

Answer 29

appears as a small rounded cystic structure or solid stalk projecting from the head of the epididymis

Question 30

what is a hydrocele?

Answer 30

an abnormal collection of fluid in the potential space between the visceral and parietal layers of the tunica vaginalis. Can be unilateral or bilateral. Can be congenital or acquired.

Question 31

What is a congenital hydrocele?

Answer 31

A congenital hydrocele results from an incomplete closure of the processus vaginalis with persistent open communication between the scrotal sac and the peritoneum. They can be associated with an inguinal hernia.

Question 32

How does a congenital hydrocele occur?

Answer 32

As the testis descends into the scrotal sac, it is accompanied by the processus vaginalis which eventually fuses and closes. Peritoneal fluid can accompany the testis on its descent and it can present as a hydrocele.
They usually resolve by 12-18 months of age.
If the processus vaginalis doesn’t fuse and close, a variety of appearances can occur

Question 33

What is an encysted hydrocele?

Answer 33

Persistence of the middle portion of the processus vaginalis results in a cyst of the cord and causes an encysted hydrocele. Usually becomes apparent in adulthood.

Question 34

How does an indirect inguinal hernia occur?

Answer 34

Persistence of the upper portion of the processus vaginalis results in an indirect inguinal canal that can extend completely into the scrotum .

Question 35

What are scrotal hernias?

Answer 35

Scrotal hernias are indirect inguinal hernias. 60% occur on the right, 25% on the left and 15% bilaterally.
Can contain loops of small bowel and fat, occasionally omentum. Surgery is usually necessary due to risk of strangulation.

Question 36

Describe the sonographic appearance of a scrotal hernia

Answer 36

Hernias are identified as heterogeneous masses in the scrotum. Movement and peristalsis may be seen in small bowel loops. Omentum is seen as hyperechoic striated appearance on ultrasound. It can be traced back to the inguinal canal.

Question 37

Intratesticular lesions are considered ____ until proven otherwise

Answer 37

Malignant

Question 38

Extratesticular lesions are considered ____ until proven otherwise

Answer 38

Benign

Question 39

What is the most common benign pathology?

Answer 39

Scrotal cysts

Benign scrotal cysts are unilocular with smooth, thin walls and posterior enhancement

Question 40

What is an epididymal cyst?

Answer 40

Epididymal cysts result from cystic dilation of the epididymal tubules.
○ Firm, hard and palpation separates these from the testis
Commonly encountered within the epididymal head but can occur anywhere within the epididymis

Question 41

What is a spermatocele?

Answer 41

Spermatoceles are benign retention cysts that arise from the rete testis they are situated in the head of the epididymis, superior to the testis and are variable in size.
○ Usually indistinguishable from epididymal cysts
○ They contain non-viable spermatozoa, lymphocytes, fat and cellular debris
○ Fine echoes and layers can be detected
○ No clinical significance

Question 42

What might scrotal calcifications represent?

Answer 42

Foci of calcifications can be representative of past inflammatory or granulomatous processes or vascular calcification. Some calcification can be scar tissue from burnt-out tumour

Question 43

What is the ultrasound appearance of a sperm granuloma?

Answer 43

Small, hyperechoic foci within the epididymis and vas deferens post vasectomy

Question 44

What is a hydrocele?

Answer 44

An abnormal collection of serous fluid in the potential space between the parietal and visceral layers of the tunica vaginalis. Acquired hydroceles are often idiopathic. Can be found secondary to neoplasm, inflammation, infection, torsion and trauma. Can be unilocular or multilocular and vary greatly in volume.
Chronic hydroceles may contain mobile echoes or debris, cholesterol crystals or protein.

Question 45

How do you distinguish between multilocular hydroceles and multiple epididymal cysts?

Answer 45

Hydroceles surround the testis and do not distort the shape of the testis.

Question 46

What is a primary varicocele?

Answer 46

A primary varicocele can be idiopathic or the result of valvular incompetence in the testicular vein causing reflux. It demonstrates increased flow with a >30% diameter increase with valsalva. Usually occur on the left side due to the anatomy of venous drainage (left testicular vein is 8-10cm longer than the right, and inserts at a right angle into the left renal vein)

Question 47

What is suspicious about a right-sided varicocele?

Answer 47

A right-sided newly discovered non-decompressible varicocele in men over 40 is suspicious of secondary origin

Question 48

What is a secondary varicocele?

Answer 48

Secondary due to compression and increased pressure on the testicular vein caused by hydronephrosis, abdominal neoplasms (RCC), retroperitoneal masses, hepatomegaly, splenomegaly or nutcracker syndrome (aorta or SMA compresses the left renal vein)
Does not increase in size with valsalva.

Question 49

What causes a sperm granuloma?

Answer 49

Vasectomy causes obstruction to the passage of sperm which can cause dilation of the vas deferens and epididymal tubules. Luminal rupture with sperm extravasation can occur which results in the formation of sperm granulomas due to the incomplete phagocytosis of extravasated sperm.

Question 50

Describe the ultrasound appearances of sperm granulomas

Answer 50

Commonly seen at the end of the vas or at the junction between the epididymal tail and the vas
Firm nodules can be painful
Variable sizes
Inflammatory hyperaemia may be seen around them
Small granulomas are hyperechoic
Larger ones can become hypoechoic with or without foci
Can be heterogeneous
Can be ovoid or round in shape

Question 51

Describe the post-vasectomy appearance of the epididymis

Answer 51

Epididymis becomes enlarged
Previously indistinguishable tubules can become apparent as hyperechoic lines within the swollen structure. Sperm can be seen swirling.