imaging and diagnosis of scrotal pathological conditions.

1. Scrotal 4 T’s
Dr/ Ahmed Bahnassy
MBCHB-MD-FRCR
Consultant Radiologist-RMH

3. Normal anatomy
• The testicles and
associated structures are
located within the
scrotum, formed by fusion
of three fascial layers and
divided by a median
septum. The septum is
contiguous with the
dartos muscle
underneath the scrotal
skin..

4. Normal ultrasound
• In the adult, the
normal testis is
roughly 20 cm3, with
an approximate
diameter of 3 to 5 cm.
• The mediastinum
testis can be seen as
a linear echogenic
band.

5. The rete testis
• The mediastinum
divides the testis into
lobules and serves as
a conduit through
which the blood
vessels, lymphatics,
and spermatic tubules
enter and leave the
testis.

6. Epididymis
• The epididymal head is located
superior to the testis, while the
body and tail run posterior to
the testis.
• The epididymis has an
echogenicity similar to or
slightly hyperechoic to the
testis. The epididymal head
may be round or triangular,
measures 5 to 12 mm in
length.
• The efferent ducts converge
and, from the epididymal tail,
become a single vas deferens,
which continues in the
spermatic cord.

7. Tunical sac
• The tunica vaginalis is a
potential space formed from the
processus vaginalis, an
outpouching of the fetal
peritoneum that descends into
the scrotum along with the
testis.
• An inner visceral layer covers
the testis and epididymis, and
an outer parietal layer lines the
scrotum. The layers join at the
posterolateral aspect of the
testis where it attaches to the
scrotal wall.

8. Tunica albuginea
• The tunica albuginea
forms a dense
capsule around the
testis, and a reflection
of this capsule along
the posterior border
(the mediastinum
testis) runs along the
superior inferior axis
of the testis.

9. Color doppler examination
• The main blood flow
to the testicle is via
the testicular artery.
The testicular artery
pierces the tunica
albuginea, forming
capsular arteries that,
in turn, form recurrent
rami that course
centrifugally toward
the mediastinum.

10. Transmediastinal artery
• In 10% to 50% of normal
testes, a single
transmediastinal artery
can be seen unilaterally
running directly within the
mediastinum and
coursing in an opposite
direction from the
recurrent rami

11. Appendix testis
Four testicular appendages, include the
appendix testis, appendix epididymis, vas • Testicular appendages
aberrans, and the paradidymis; 92% of are remnants of the para-
males have an appendix testis, and 34%
have an appendix epididymis
mesonephric ducts and
are found at the upper
pole of the testes in a
groove between the testis
and the head of the
epididymis.They are
usually of similar
reflectivity to the
epididymal head and are
ovoid or sessile shaped,
but may be pedunculate.

12. The 4 T’s
• Torsion
• Trauma.
• Tumor.
• Testiculitis (orchitis)

13. I-Testicular Torsion
• Torsion usually occurs in the absence of any
precipitating event .
• But factors that can precipitate torsion includes
1. Trauma (4 to 8 percent of cases )
2. Increase in testicular volume (often associated with puberty)
3. Testicular tumor
4. History of cryptorchidism
5. Spermatic cord with a long intrascrotal portion

14. Torsion
• Torsion initially obstructs venous return.
Subsequent equalization of venous and arterial
pressures compromises arterial flow, resulting
in testicular ischemia
• The degree of ischemia depends on the
duration of torsion and the degree of rotation of
the spermatic cord
• Ischemia can occur as soon as four hours after
torsion and is almost certain after 24 hours

15. Torsion
• In one study, investigators quoted a testicular
salvage rate of 90 percent if detorsion occurred
less than six hours from the onset of symptoms
• this rate fell to 50 % after 12 hours, and
• to less than 10 % after 24 hours

16. Torsion
• Color Doppler imaging
provides both structural
and physiologic
information about the
vascular integrity of the
testis. Unilateral
diminished or absent flow
is the most accurate sign
of testicular torsion .

17. Within 6 hours, the
affected testis may be
slightly enlarged, with
normal or decreased
echogenicity .
After 24 hours, echogenicity of
the testis becomes
heterogeneous, a sign of loss of
viability. The epididymal head
may be enlarged because of
involvement of the deferential
artery.

18. II-Trauma
• Ultrasound shows
heterogeneous echogenicity
within the testis due to areas of
hemorrhage or infarction.
Other findings include
irregular, poorly defined
borders, scrotal wall
thickening, and hematocele .
• The tunica is disrupted with
testicular rupture, and there
may be diminished blood flow
in the disrupted capsule.

19. Intratesticular haematoma

20. Extratesticular haematoma

21. Testicular fracture

22. III-Scrotal tumors
• Testicular cancer has 3 main types—
• (1) germ cell tumors,
• (2) non–germ cell tumors,
• and (3) extragonadal tumors.
• Germ cell tumors, which are the most
common, are classified as either
seminoma or nonseminoma, based on
histology.

23. Seminoma
• Scrotal ultrasonography
commonly shows a
homogeneous
hypoechoic intratesticular
mass. Larger lesions may
be more inhomogeneous.
• Calcifications and cystic
areas are less common in
seminomas than in
nonseminomatous
tumors.

24. Non Seminomatous Germ Cell
tumours
• NSGCTs refer to the germ cell tumors that
contain embryonal stem cells.
• The 4 histologic classifications of NSGCTs
include (1) embryonal carcinoma, (2)
teratoma, (3) choriocarcinoma, and (4)
yolk sac tumor.

25. In patients with testicular tumors, scrotal
sonograms usually demonstrate a mass in the
testis, usually confined by the tunica
albuginea. This mass may contain
microcalcifications and areas of hemorrhage
and is typically heterogeneous in appearance.

26. Non Germ cell Tumors
Gonadoblastoma; granulosa cell tumor; leydig cell tumor; sertoli cell tumor.
Sertoli-cell tumors are the most
common gonadal stromal tumors
in prepubertal children. These
tumors tend to appear as painless
masses in boys younger than 6
months and produce no
endocrinologic effects; 14% of
patients present with
gynecomastia.
Leydig-cell tumors are the second
most common gonadal stromal
tumors in children and are also
benign. These tumors most often
occur in boys aged 5-10 years,
and the synthesis of testosterone
may produce precocious puberty.

27. Other pre—Pubertal umours
Juvenile granulosa-cell tumors appear as cystic, painless testicular masses.
They almost exclusively appear in the first year of life and most appear by
age 6 months. These tumors are hormonally inactive and benign.
Gonadoblastoma occurs in association with disorders of sexual
development (intersex).
Cystic dysplasia of the testis is a benign lesion that is often associated with
ipsilateral renal agenesis or dysplasia.
Leukemia and lymphoma are the most common malignancies to affect the
testis secondarily and account for 2-5% of all testis tumors; most present
bilaterally.
Paratesticular structures can give rise to various benign (lipoma, leiomyoma,
hemangioma, or fibroma) and malignant tumors; however, these are
extremely rare. Rhabdomyosarcoma is the most common malignant tumor
(17%) and may arise from the distal spermatic cord and appear as a scrotal
mass or hydrocele.

28. Lymphoma

29. Testicular microlithiasis
• Testicular
microlithiasis (TM) is
defined as multiple
(>5) echogenic
nonshadowing 2- to
3-mm foci randomly
scattered throughout
the testicular
parenchyma

30. IV-Orchitis

31. Testicular abscess

32. Epididymitis

33. Venous infarction
• Venous infarction of the testis
may occur in patients with severe
epididymo-orchitis where
localized oedema occludes the
venous drainage of portions of
the testis or the entire testis.
• The testis appears of low
reflectivity, is swollen, and there
is an absence of colour Doppler
flow.
• Indirect evidence of venous
infarction is suggested by
reversal of arterial flow in diastole
when the testicular artery in the
spermatic cord is interrogated
with spectral Doppler ultrasound.

34. Infection and arterial infarction

35. Fournier gangrene
Fournier's gangrene is a
aggressive necrotizing
fasciitis of the perineum,
which occurs most
frequently in males aged
50–70 years, associated
with diabetes mellitus.
Fournier's gangrene
usually arises secondary to
local infection with multiple
organisms involved:
Klebsiella spp.,
Streptococcus spp.,
Proteus spp. and
Staphylococcus

37. Polyorchidism.
• Polyorchidism is a rare anomaly
described as the presence of more than
two testes.
• type A: the supernumerary testis lacks
either an epididymis or vas deferens.
• Type B: the supernumerary testis has an
epididymis but no vas deferens, and the
epididymis may be connected to the
normal ipsilateral testis (type B2) or
have no connection (type B1).
• Type C: the supernumerary testis has a
separate epididymis, but shares the vas
deferens with the ipsilateral testes either
in a parallel or longitudinal fashion.
• Type D: the supernumerary testis may
have a completely separate epididymis
and vas deferens, and is the least
common.

38. Cystic transformation of rete testis
• Dilatation of the rete testis is
very common and mostly
seen in patients over 50
years of age. Rete testis
dilatation is often associated
with either post-infectious or
post-traumatic epididymal
obstruction.
• Frequently an epididymal
abnormality such as a
spermatocele or dilated
efferent ducts following a
vasectomy can be found on
ultrasound

39. Two-tone testes
• The two-tone testis is an eloquent
term, used to describe the
appearance of a normal testis
that is transacted by trans-
mediastinal vessels, resulting in a
neatly divided manifestation of
different reflectivity.
• The portion nearest the probe is
of normal expected testicular
reflectivity whereas the portion
distal to the vessel is of
decreased reflectivity caused by
imaging obliquely through the
walls of the trans-mediastinal
vessels.

40. Segmental testicular infarction
• Segmental testicular infarction is rare
Predisposing factors to segmental
infarction include polycythaemia, intimal
fibroplasia of the spermatic artery,
sickle cell disease and trauma, or
idiopathic origin.
• Clinically segmental infarction usually
presents with testicular pain, whereas a
malignant lesion presents as a painless
lump.
• The ultrasound features are those of a
low reflective area, which may be
wedge-shaped, with no posterior
acoustic enhancement and may be
associated with focal expansion of the
testes. There is poor or absent colour
Doppler flow whereas malignant lesions
normally demonstrate increased colour
Doppler flow.

41. Intra-testicular varicocele
• An intra-testicular varicocele
is an uncommon ultrasound
finding with an incidence
quoted at <2% in a
symptomatic population.
The ultrasound
appearances of an intra-
testicular varicocele are
anechoic serpiginous or
cystic structures radiating
from the mediastinum testis.
An intra-testicular varicocele
will behave in a similar
fashion to an extra-testicular
varicocele, increasing in
size and demonstrating
retrograde flow on Valsalva
manoeuver.

42. Splenogonadal fusion
• Two types of splenogonadal
fusion are described: in the
more common continuous
type, a cord, which may be
beaded with small splenunculi,
connects the accessory spleen
to the actual spleen whereas in
the discontinuous type no cord
is present
• If the diagnosis is considered
preoperatively, a 99mTc-
sulphur colloid scan is
diagnostic, demonstrating
tracer uptake within the
accessory spleen and splenic
tissue

43. Epidermoid cyst
• The “onion-ring”
appearance corresponds
to alternating layers of
compacted keratin and
loosely dispersed
desquamated squamous
cells.
• A similar appearance has
been described in a
teratoma.
• The absence of colour
Doppler flow and
negative tumour markers
increases diagnostic
confidence.

44. Testicular oedema
• Testicular oedema results in
fluid tracking into the
interstitial tissues of the testis
as a consequence of marked
subcutaneous oedema of the
scrotal sac. This gives rise to
low reflective linear branching
throughout the testes giving a
‘crazy paving’ appearance.
The linear branching low
reflective areas demonstrate
no colour Doppler signal.

45. Dancing megasperm’
• An unusual
appearance, estimated
at 0.6%, is that of
multiple small echoes
within an enlarged
epididymis, with
apparent independent
movement.Patients
with this appearance
had a history of a
vasectomy or previous
surgery to the scrotum,
and all were
symptomatic for scrotal
pain

46. Torsion of an appendix testis
• The ultrasound
appearances of a torted
appendix testis are a
rounded mass with
variable reflectivity at the
superior aspect of the
testicle with surrounding
increased Doppler flow
and a small hydrocele.
ultrasound will
demonstrate the appendix
within a small localized
hydrocele.

47. ‘Snowstorm’ hydrocele
• This appearance is
attributed to the presence
of cholesterol crystals
circulating within the fluid
or to high protein content,
which are of no clinical
significance.
• With the use of higher
power output techniques,
with the presence of florid
echoes within the
hydrocele, the swirling
particles give rise to a
‘snow storm’ appearance.

48. Testicular sarcoid
• Sarcoidosis is a multi-
system disorder
characterized by non-
caseating epitheloid
granulomas. The
diagnosis is often one of
exclusion as many other
conditions have similar
histology; much reliance
is placed on the
associated clinical
findings and
radiographic
appearances.

49. Acute scrotum in children with
Henoch-Schonlein purpura
• The cause of the acute scrotum in the context of
HSAPS is known to be vasculitis and not
torsion .
• Complications involving the male genital system
are unusual.
• They include oedema and haematoma of the
scrotal wall and spermatic cord, testicular
haemorrhage and subcapsular testicular
haematoma, epidydimitis, orchitis and penile
swelling. The signs often mimic conditions that
require surgical intervention, especially torsion of
the spermatic cord.

50. Role of color doppler
• The decision to treat expectantly should
be supported by high resolution colour
Doppler sonography confirming increased
testicular blood flow in support of the
diagnosis of vasculitis.