3. • The scrotum is a fibromuscular cutaneous sac, located
between the penis and anus
• The scrotal wall is composed of several layers and normally
measures 2-8 mm
Gross anatomy
4. SUPERFICIAL TO DEEP LAYERS
Superficial fascia and dartos muscle
Internal spermatic fascia: continuation of
transversalis fascia
Tunica vaginalis
Tunica albuginea which covers the testes
Cremasteric fascia: continuation of internal
oblique abdominis muscle aponeurosis
External spermatic fascia: continuation of
external oblique abdominis muscle aponeurosis
Pigmented skin with rugal folds
7. The normal adult testes are located in the scrotum and are oval in shape.
At birth : 1.5 cm (length) x 1 cm (width) and 4 mL volume at puberty .
Normal adult : 3 cm (AP) x 2-4 cm (TR) x 3-5 cm (length)
Volume : 12.5-19 mL.
However, the size of the testes decreases with age
GROSS ANATOMY OF TESTIS
8. reflected on the
internal
surface of the
scrotum
covers the
surface of the
testis and the
epididymis
COVERINGS OF
TESTIS
It penetrates
into the
parenchyma of
each testicle
dividing it into
lobules.
Parietal layer Visceral layer
Tunica vaginalis( pouch of serous membrane
Tunica albuginea (fibrous capsule)
9. Epididymis measures 6 cm in length
Divided into three parts: head, body and tail.
Head – measures 5 to 12 mm
Body – Formed by the heavily coiled duct of the epididymis measures 2
to 4 mm
Tail – The most distal part of the epididymis. It marks the origin of the
vas deferens meaures 2 to 5 mm
EPIDIDYMIS
Head
Body Tail
10. • It begins at the deep inguinal ring, lateral to the inferior epigastric
vessels and extends through the inguinal canal, terminating at the
superficial inguinal ring into the scrotum
SPERMATIC
CORD
Contents:
3 arteries: artery of the ductus deferens, testicular artery, cremasteric artery
3 nerves: genital branch of the genitofermoral nerve, parasympathetic and sympathetic nerve fibers
3 fascias: external spermatic fascia, cremasteric fascia, internal spermatic fascia
3 other things: ductus deferens, pampiniform plexus, lymphatic vessels
11. Plexus of veins (pampiniform plexus)
Testicular veins
Right testicular vein Left testicular vein
Inferior vena cava (IVC) Left renal vein
ARTERIAL SUPPLY
Aorta
Testicular Artery
Capsular Arteries
Centripetal Arteries
VENOUS DRAINAGE
17. NORMAL MRI OF THE SCROTUM
Axial T2 coronal T2 Sagittal
T2
sagittal fat-saturated
postcontrast T1
Coronal T2 Sagittal T2
18. Testicles descend into the scrotum between the
7th to 9th month of fetal life.
Processus vaginalis appears at about 13 weeks
of fetal development
Processus vaginalis:
▪ Upper portion ---> closed
Lower portion ---> remain open
(tunica vaginalis)
DEVELOPMENTAL
ANATOMY
19. ▪ TUNICA VAGINALIS:
✓ Anchors the gubernaculum,epididymis
and testis to the posterior wall
✓ Creates the vertical lie of the testis
within the scrotal sac.
Abnormal high insertion of tunica
vaginalis onto the testicle
testicle swing freely → bell-clapper
deformity.
23. Epididymitis is the most common cause of acute scrotum.
Etiology:
Nonspecific bacterial infection.
Ascending spread via the vas deferens. e.g., in urethritis or
prostatitis.
Granulomatous epididymitis in sarcoidosis. tuberculosis. syphilis.
leprosy.
Acute pain and tenderness in the scrotum.
Fever, dysuria, or pyuria with urethral discharge may be present
EPIDIDYMITIS
24. ULTRASOU
ND
Enlarged, hypoechoic,
heterogenous. (diffuse >focal)
Increased vascularity on color
Doppler.
May be reactive hydrocele.
May be associated thickened scrotal
wall & spermatic cord.
28. Occur from TB, mumps or retrograde
infection form the lower urinary tract.
Enlarged, hypoechoic, heterogenous.
Increased vascularity on color Doppler
exam.
ORCHITIS
29. FOURNIER’S GANGRENE
Fulminant gangrene of the scrotal wall
At risk: DM, AIDS, Chronic illness
Underlying Epidydimo-orchitis common
On US:
- Marked Scrotal wall thickening
-Scattered echogenic foci : gas
30.
31. Intra-testicular masses:
Usually malignant
Extra-testicular masses:
Usually benign
Young males between 20-30 years.
Symptoms are lump, swelling and heaviness.
Pain < 10% of cases.
NEOPLASMS
35. Seminoma:
• Hypoechoic
• Homogenous (heterogenous iflarge)
• Well defined margins
• Rarely extendingextratesticular
• Calcifications and cystic changesare less common
• Internal vascularity
36. • Metastases to the para-aortic lymph nodes
at the level of the renal vessels are the
typical first site of spread, owing to the
lymphatic drainage of the testes relating to
embryologicaltesticular descent.
• The nodal metastases are often bulky, of
homogeneous density, and tend to encase
surroundingvessels.
CT
37. MRI
• Seminomas appear as multinodulartumors of uniform signal intensity
• T2: hypointenseto normal testicular tissue
• T1 C+ (Gd): heterogeneousenhancement
• DWI/ADC: restricted diffusion is seen (feature of malignant tumors)
Axial T2
Coronal T1
Sagittal T1 C+ fat
sat
41. Check for metastatic retroperitoneallymph nodes
TESTICULAR TUMORS
The left and right testes have differing lymphatic drainage. The left testis primarily drains
through the para-aortic lymph nodes. The right testis primarily drains through theaortocaval
nodes.
42. Non-germ cell tumors:
• Sertoli cell, leydig cell and gonadoblastoma
• 30-40% are hormonallyactive
• Majority are benign
• Variable appearance,so we can't differentiate benign from malignant
leydig cell tumor
43. Testicular lymphoma:(Primary)
• Men > 60 years
▪ Common in patients with HIV
▪ Large cell Non Hodgkinlymphoma
▪ 90% are disseminatedat diagnosis
Metastases:
• Most common in Adults: Lymphoma,Lung, Prostate
• Known as ‘Sanctuarysite’ in children with acute Leukemia
45. ▪ Bell clapper deformity.
- Congenitalabsence of gubernaculum
▪ Salvage rate is related to the time since the beginning torsion:
▪ < 6 hours 100 %
▪ 6-24 hours 50%
▪ > 24 hours 20%
TESTICULAR TORSION
46. ULTRASOUND
• <6hrs: may be normal
• unilateral enlargement
• Markedly hypoechoic
• Absent or decreased color doppler flow
• Whirpool (Sprematic cord)
50. TORSION OF TESTICULAR / EPIDYDIMAL APPENDAGE
Most common cause of acute scrotal pain in child
Clinically: Blue dot sign(20%)
on US:
• Round, Enlarged
• Increase flow in periphery
• hydrocele and scrotal wall thickening
Management:Conservative
51.
52. TESTICULAR
INFARCTION
Segmental Testicular infarction:
▪ Present with acute pain.
Ultrasound:
Wedge shaped,hypoechoic area, extending to the periphery of testicle
absence of color Dopplerflow in the hypoechoic region
slight retraction of the tunica albuginea adjacent to the lesion may be seen
53. TRAUMA
• Interruption of the tunica albugenia
and extrusion of seminiferous tubules
Clinical importance:
• 10x decreased orchiectomy rate if dx'd within 3 d
• Increased risk of infertility with delayed repair
TESTICULAR RUPTURE
58. INTRA-TESTICULAR CYSTS
• Benign Cystic lesions
• More common in males > 40 years
• Size: 2mm-2cm
• Can be multiple
• Non palpable
Ultrasound:
• Roundedor oval anechoic structure
• Posterior acoustic enhancement
• Along the course of mediastinum.
• No internal vascularity
59. EPIDERMOID CYST:
• Benign
• Size: 1-3 cm
Ultrasound:
✓ Echogenic rim
✓ Onion skin or target appearance due to layers of keratin.
✔ No flow on color Dopplerexamination.
60. TUBULAR ECTASIA OF THE RETE TESTIS
• Obstruction to flow of spermatozoa→→reflux into the rete testis.
• Affects men > 55 years.
Ultrasound:
Tiny tubular cystic spaces along the mediastinum.
No flow on color Doppler examination.
Associated epididymalcysts or spermatocele.
61. EPIDIDYMAL CYST / SPERMATOCELE:
• The most common epididymalmass.
• Often used interchangeablyto describe the same lesion.
• Painless palpable mass.
• Epididymalcysts Serous fluid.
• Spermatoceles→nonviable spermatozoa and debris.
Ultrasound (epididymal cyst):
✓ Anechoic without internal echoes Posterior acoustic
enhancement
✓ Solitary or multiple
✓ Larger cysts may contain septations and may mimic
hydrocele.
✓Any part in the epididymis.
→
62. EPIDIDYMAL CYST/SPERMATOCELE:
• Ultrasound (Spermatocele):
✓ Anechoic with internal echoes
✓ Posterior acoustic enhancement
✓ Solitary or multiple
✓ Larger cysts may contain septations and may mimic
hydrocele.
✓ Almost always in the epididymalhead.
63. Abnormal dilatation and tortuosity of the pampiniformplexus
of veins.
May affects male fertility.
Incompetence testicular vein → reflux of blood down into the
pampiniformplexus.
More common on the left side.
Isolated right-sidedvaricoceles are rare and should raise
concern for variant anatomies like situs inversus or intra-
abdominalpathologysuch as a retroperitonealmass.
The normal diameter of pampiniformplexus veins < 1.5mm.
VARICOCELE
66. HYDROCELE
• Abnormal accumulation of serous fluid in between the layers of tunica vaginalis
• Congenital or acquired.
• Hydroceles in neonates and infants are congenital and are typically associatedwith
patent processus vaginalis.
• Acquired:
✓ Trauma
✓ Infection
vascular insult
Tumors
67. ULTRASOUND:
Simple anechoic fluid collection.
+/- internal echoes.
+/-contain septations
No internal vascularity by color Doppler
74. CRYPTORCHIDISM
Cryptorchidism refers to an absence of a testis in the scrotal sac. It may refer to an undescended testis
Persistent undescended testis will atrophy and has a higher risk of testicular tumor
75. ULTRASOUND
• Study of choice for inguinal testis
• lack of a testis in the scrotal sac
○ Ovoid, homogeneous, well-circumscribed mass
○ Smaller than normally descended testis
○ Echogenic line of mediastinum testis helps differentiatefrom other soft tissuesmasses
76. • Coronal T1W images can show the gubernaculum testes and spermatic cord, which can be followed to
locate the undescended testes. Also, an ectopic pelvic or retroperitoneal location of testes can be
identified.
• Diffusion-weighted MRI shows the normal testes as markedly hyperintense structures,
differentiating them from surrounding structures
Coronal T1W Diffusion-weighted MRI
: choice for intraabdominal testes
MRI
External pudendal veins
external pudendaL artery
Anterior scrotal artery
internal pudendal artery
Posterior scrotal artery
and the cremaster artery, which is a branch of the
inferior epigastric artery.
testes measure approximately
Head – The most proximal part of the epididymis.
The spermatic cord (TA: funiculus spermaticus) is the tubular structure that suspends the testes and epididymis in the scrotum from the abdominal cavit
The testes are supplied by testicular arteries, arising from the aorta, just below the origin of renal arteries.The testicle is supplied by the
testicular artery, which enters the tunica albuginea foring capsular arteries, which in turn give rise to centripetal
arteries that penetrate into the testis toward the mediastinum.
The venous drainage of the testis is via
the pampiniform plexus to gonadal veins, which drain to
the inferior vena cava (IVC) on the right and to the left
renal vein on the left.
a) Gray scale side-by-side view of both testes in a single image. This image is important to confirm the presence of two testes
b) Gray scale ultrasound in transverse and longitudinal planes used to measure the testicular volume
Fig: (a) Sagittal grayscale image shows a normal testicle with homogeneous echotexture. The scrotal wall contains several layers of muscle and fascia, which cannot be discerned by ultrasound, contributing to its heterogeneous echogenic appearance. The thin hyperechoic line surrounding the testicle is the tunica albuginea. The epididymis is slightly hypoechoic compared to the testicular parenchyma.
(b) Sagittal grayscale image shows a linear hyperechoic line representing the mediastinum testis.
(c) Sagittal image with color and spectral Doppler shows normal testicular perfusion throughout the testicle and a normal low resistance arterial spectral waveform. RI Testicular artery -0.46 to 0.78
(d) Transverse image with color Doppler including both testicles shows symmetrical flow.
The tunica albuginea appears as a thin hyperechoic rim encasing the testicle, which invaginates in the central testicle as a hyperechoic band corresponding to the mediastinum testis.
The spermatic cord has a straight course from the external inguinal ring along the posterior border of the testicle, with a normal transverse diameter of less than 5mm.
Remnants of embryonic ducts give rise to various like......... However, both vas aberrans and paradidymis are not usually seen during imaging.
a) ovoid appendix testis from the superior testicular pole (arrow)
b) There is a short pedunculated mass arising from the head of the left epididymis.
testes contain four appendages:
a) ovoid appendix testis from the superior testicular pole (arrow)
b) There is a short pedunculated mass arising from the head of the left epididymis.
testes contain four appendages:
a) ovoid appendix testis from the superior testicular pole (arrow)
b) There is a short pedunculated mass arising from the head of the epididymis.
(A) Axial and (B) coronal T2-weighted images show the normal T2 hypointense lobular septa (thin white arrows) converging on the mediastinum testis (arrowhead).
The images also show a portion of the epididymis (thick arrow), which is T2 hypointense relative to the testis.
The tunica albuginea appears as a thin T2 hypointense line around the testis (black arrows in B); note also the urethra (curved arrow in B) in the corpora spongiosum. Physiologic fluid is present around the testis (asterisk).
(C) Sagittal T2 and (D) sagittal fat-saturated postcontrast T1 images demonstrate the epididymis (fat arrows) as a low-signal structure along the posterior aspect of the tstis, which is mildly hyperenhancing relative to normal testicular parenchymal. Note the lobular septa (thin white arrows in C) and the scrotal wall (arrowheads).
(E) Coronal T2-weighted image show a low T2 signal structure (arrowhead) in the testis corresponding to a vessel. Note also the epididymal head (thick arrows) and a small hydrocele (asterisk). Partially visualized is a larger left hydrocele (2 asterisks) in this patient with left epididymo-orchitis.
(F) Sagittal T2-weighted image demonstrating the appendix testis (arrow).
Testis develops within the abdomen
Process vaginalis appears as outpouching of parital peritoneum though which testis descent into scrotum
Double layered testiscular covering called tunica vag
Tunica vag helps in suppoting each testis in place
Which will lead to testicular torsion
Tun vag 2 layers- outermost layer parietal layer lines the scrotal wall nd inner layer reflects on testicle itself
Creates potential space between them which has littlt amount of fluid but execess amount of fluid lead to condition called hydrocele
scotal infection can invovle epidydymis or epydidimis testis or only testis
thickened
normally epudiddimis is less vascular
sometimes inf starts in epi and affects testis also
diffusely enlared testis
Enlarged, hypoechoic,
heterogenous. (diffuse >focal)
Increased vascularity on color Doppler.
epididymis is thickened and heterogenous nd on doppler hyperemic, .
A focus of mixed echogenicity and several smaller hypoechoic foci In the epididymal tail, all demonstrating a lack of internal flow - most compatible with abscesses.
complex, heterogeneous fluid collection in the scrotal sac with septa
Transverse color Doppler image showing the asymmetry of vascularity, with the inflamed left testis showing much more color signal than the normal right testis (RT).
infection isolated to testis is called orchitis
Fig. 2. A & B Sonographic image show thickened scrotal wall and multiple echogenic foci with dirty shadowing, representing gas in soft tissues.
Fournier gangrene in a 49-year-old man. (a, b) CT scans show inflammation and air in the scrotum (arrows in a) and left inguinal canal (arrows in b).
it is important determine wheteher a mass is intra or extra
testicular tumors occurs in
pain is unsual and less 10 of testicular cancer presnt with pain
which has spectrum from benign with teratoma being most bening end of the spectrum and choriocarcinoma being most malignant in spectrum
The testes have normal size and vascularity, showing multiple microcalcifications foci,
Within the upper portionsthe testis, there is a well-definedlobulated hypoechogenic nodule that shows increased internal vascularity, but no cystic or calcified components.
The epididymis have normal sonographic appearances. No hydrocele.
Figure: There is a large, conglomerate retroperitoneal lymph nodal mass with cystic necrotic areas within and heterogeneous enhancement noted in the paraaortic region.
The lymph nodal mass is encasing the aorta
AXIAL T2 wieght images showing heterogenous testis with intemridtae signal intesty
After gadolinium administration, there is heterogeneous enhancement of the tumor associated with multiple internal enhancing septa
Figure: Ultrasonography scrotal image
showing a heterogenous lesion with solid (line arrow) and cystic (chevron arrow) components in the right testis and
(b) raised vascularity of the testicular lesion (block arrow).
A large heterogeneous lobulated hypoechoic mass measuring about 1.9 x 3.4 cm is seen in the right testis.
The mass is invading the tunica albuginea posteriorly and has multiple tiny internal calcifications.
The mass is hyper vascular on color Doppler ultrasound examination.
Small right hydrocele.
Ultrasound demonstrates a heterogeneous right testicular mass with predominate cystic components and a hypoechoic solid component showing marginal calcific foci.
when we see intratesticular lesion,always check for
.US of teratoma seen as a low echo lesion containing an area of central calcification.
Axial CT showing left para-aortic lymph node from a left sided tumour.
Small hypoechoic nodule in the mid portion of the right testis with surroundig normal parnchyma. Some internal vascularity detected on color Doppler images
considered as large
The blood-testis barrier limits chemotherapy from reaching the testis, and therefore the testis can act as a sanctuary for leukemic cells
A bell clapper deformity is a predisposing factor in testicular torsion in which the tunica vaginalis has an abnormally high attachment to the spermatic cord, leaving the testis free to rotate. Bell clapper deformity predisposes to intravaginal torsion of the testis.
guburbaculum hold the testis in place inferior aspect to scotum and abscnece cause testis to twist around the spermatic cord and abruting the blood flow to testis
if tosion is discoverd and operated within ... then salvagelbilty of testis is excellent
The right testis appears slightly swollen, with diffuse coarsened echotexture and no detectable parenchymal flow on Doppler examination. Findings are highly suggestive of testicular torsion.
The right epididymis appears enlarged/swollen and heterogeneous in echotexture.
There is also associated mild right sided hydrocele as well.
The right testis is diffusely hypoechoic with heterogeneous texture and no intratesticular vascularity noted. Twisted spermatic cord at scrotal neck which is enlarged and shows whirlpool appearance consistent with a twist. Minimal reactive turbid hydrocele is noted.
Ultrasound demonstrates an enlarged, hypoechoic left testis with no internal vascularity. There is a complex left hydrocele.
Figure: An echogenic right testicle is shown in a patient with 2 days of testicular pain
Arrowheads point to hemorrhage within the "missed" torsion.
This is not typically seen in acute torsion,
vascular flow at the periphery of the testicle. Lack of color flow within the central portion of the testicle suggests torsion.
Surgery confirmed the findings.
The normal appendix testis is 1 to 4 mm in length, and it is oval or pedunculated in shape.
mmediately adjacent to the head of the left epididymis there is a round lesion measuring approximately 1 cm. It is relatively hyperechoic in comparison to the epididymis and testis and there is central heterogeneity. There is vascularity surrounding this lesion but no internal vascularity.
Ultrasound images show an ill-defined hypoechogenic, heterogeneous lesion, with a wedge shape that had its apex at the testicular mediastinum and a peripheral base. There was a complete absence of flow at color Doppler on the inside, while it was preserved of the rest of the testicular parenchyma.
Rupture of right testis, with tunica albuginea defect in the inferomedial portion of the testis
Increased vascularity of the right testis, apart from at a heterogenous, hypoechoic component anteriorly with little flow, likely small contusion/haematoma.Complex right haematocele
Enlarged right testicle with heterogenous echotexture.
There are multiple ill-defined hypoechoic patchy areas within the right testis. This could represent testicular contusion.
On color Doppler there is loss of vascularity in these hypoechoic areas.
.
here this testis is heteregenous with hypoechoic band creating a parenchymak discontinuity
this hypoechoic line representin testiculat fracture
blood collection in tunica vaginalis is called hemotocele
A 7 × 5 mm simple cyst in the upper pole of an otherwise normal testis - well circumscribed, anechoic area with smooth wall and posterior acoustic enhancement
There is a well circumscribed intratesticular mass at the upper pole of the right testis. The mass contains alternating hyperechoic and hypoechoic rings, demonstrating a lamellar ("onion skin") appearance. There is no vascularity within the testicular lesion. The surrounding testis is normal. These findings are suggestive of an intratesticular epidermoid cyst
Grayscale ultrasound of the left testis demonstrates cystic areas within the mediastinum testis, consistent with tubular ectasia of the rete testis
Color.
Doppler ultrasound of the right testicle demonstrates avascular cystic areas within the testis with a cystic area within the epididymal head.
These findings are consistent with tubular ectasia of the rete testis with associated spermatocele.
Ultrasound demonstrates a well-circumscribed anechoic cystic mass in the head of the epididymis, consistent with an epididymal cyst.
There is well defined cystic lesion seen within the head of the right epididymis, with posterior acoustic enhancement, and associated with fine low-level internal echoes.
Multiple dilated serpingeous vessels superior to the upper pole of the left testicle. These measure upto 4mm even in the supine postion.
Avid doppler flow within. The appearances are exaggerated during standing and the Valsala maneourve. No flow reversal.
Colour Doppler images obtained at rest (a) and during Valsalva (b) showing dilated veins to the inferior pole of the testis (T) with refux during Valsalva
Intra-testicular varicocele. very rare charcterised by intratesticular dilatation of veinsand usually seen in the presence of ipsilateral extratesticular varicocele.
A serpiginous structure (arrow) coursing through the central aspect of the testis with ''tumbling'' echoes within.
Colour Doppler image with the patient performing the Valsalva manoeuvre demonstrating colour Doppler flow.
Large right hydrocele with normal testes.
When obliteration fails , peritoneal fluid can enter the deep inguinal ring and flow into the scrotum via the patent processus vaginalis. When this occurs without intra-abdominal contents, it is known as a communicating hydrocele
When obliteration occurs above the testis but fails at the deep inguinal ring, peritoneal fluid may flow through the patent processus vaginalis without entering the scrotum.46 This is known as a funicular hydrocele
When closure occurs both at the deep inguinal ring and directly above the testis, an encysted hydrocele may result.
(a) Fluid is seen within the patent processus vaginalis (star) entering at the deep inguinal ring (arrow) and extending distally. (b) Fluid shown extending through the superficial inguinal ring (arrow). (c) Fluid (asterisk) extends into the right hemi-scrotum surrounding the right testis (RT). Fa.
large cyctic structure that doesnt surround the testicle and has communicaton high up in perotneal cavity
small cystic lesion with no communications
The testes develop in the abdomen and at ~21 weeks of gestation migrate toward the inguinal canal through the deep inguinal ring.
The migration is complete at ~30 weeks.
The gubernaculum is the ligament which connects the testes to the scrotum. Under hormonal influence (probably testosterone), the gubernaculum contracts, and the testes descend into the scrotum.
Scrotal ultrasonography of undescended testis: (a) Normal testis in the scrotum (b) Atrophic and decreased echogenicity of the contralateral testis of the same patient seen in the inguinal region
Oval testis-like structure is noted at the pelvis adjacent, and medial, to the left external iliac vessels just lateral to the urinary bladde.