Color of the William William

Doppler Scrotum1

G. Horstman, D. Middleton,

G. LelandMelson, Barry A Siegel,

US

MD MD

MD MD

Color Doppler ultrasonography (US) is an increasingly important tool in the evaluation of the scrotum, especially in acute scrotal disorders. With this modality, arterial flow is readily detected in the normal spermatic cord and testis but is not seen in the epididymis; venous flow is not seen anywhere in the normal scrotum. Scrotal inflammatory lesions appear as hypervascularity of the epididymis or testis, even though gray-scale findings may be normal or nonspecific. Testicular torsion is demonstrated by an absence or marked decrease in the number ofvisible vessels. Small tumors ( < 1.5 cm) are hypovascular, and larger tumors ( > 1 5 cm) are hypervascular. The modality also demonstrates Valsalva maneuver-induced venous flow augmentation in varicoceles and altered flow in testicular tumors. Color Doppler US allows for evaluation of morphologic findings and perfusion and enables accurate diagnosis of most scrotal disorders. .

.

INTRODUCTION

In the

past

decade,

an extremely tum.

Its

scrotal

high-resolution

valuable

primary

role

and

masses

has

sumed the

corresponding

phy

provides

allow

role

evaluation

Color

of both

Doppler

multaneous color.

Therefore,

display

Index terms: Epididymitis, 847. 12984 #{149} Testis, abscess, 847.40

#{149} Testis,

RadloGraphics I

From

Louis, quests

Institute 25,

the

#{149} Orchitis, #{149} Testis,

noninvasive

12984

847.20 neoplasms,

Ultrasound

847.329, (US),

#{149}

scintigra-

modality

would

allows

for a si-

that scale

gray-scale

diseases, 847.34

Doppler

ideal

technique in gray

of both

#{149} Scrotum,

has asbecause

perfusion.

morphology

strengths

morphologic

847.20, #{149} Testis,

and US

847.30 torsion,

blood

and

#{149} Scrotum,

847.

143

flow

in

testicular

US studies, trauma,

#{149} Testis,

studies

11:941-957

Mallinckrodt February

new

the

Unfortunately, An

of

1991;

ofa

of Radiology, Magna

revision

Washington

Cum

Laude

requested

April

award

University for a scientific

18 and

receivedjune

School

of Medicine,

exhibit

at the

510 1990

12; acceptedJune

S Kingshighway

RSNA

scientific

14. Address

Blvd,

St

assembly. reprint

re-

to W.D.M.

RSNA,

See

847.

MO 631 10. Recipient

Received

C

US studies, 1991;

the

847.20 847.20

and

localization

inflammation

specific.

as

scro-

to evaluate

scintigraphy

scrotal

information.

of tissue

it combines

because

used

testicular

more

morphology

US is a relatively

real-time

are

morphologic

scrotal

limited and

of the and

been

Conversely,

in perfusion

limited

characterization,

of torsion

has emerged

(US)

abnormalities

US has also

is more

nonspecific. diagnosis

changes relatively

detection,

its value

are in the

morphologic

Although

torsion,

entities

a primary

in the

collections.

and

in these

ultrasonography

of evaluating

been

fluid

epididymo-orchitis changes

gray-scale

means

the

1991 commentary

by Cochran

following

this

article.

941

scintigraphy

and

functions

as an

all-encom-

passing

scrotal imaging technique. Early reports on the use of color Doppler US in the scrotum have been encouraging (1-6). We believe it will assume an increasingly important role in the future, particularly in the evaluation of acute scrotal diseases. To date, we have performed over 600 color Doppler US examinations of the scrotum. In some cases, the color Doppler US results have been

correlated applicable,

When

color

Doppler

ings

and

with we

those have

of scintigraphy. also correlated

US results

clinical

with

outcome.

article

U

potential

pitfalls

of the

Doppler

performed

scrotum

US of the with

the

supported the thighs.

tween performed

patient

supine

with

a color

probes

shifts

and

fore,

higher

for difPower output

is varied,

of the

be the

beare

Doppler these

signals

The disadvantage quencies is poorer ence, a transmitted the best compromise tivity

and

US of the

tissue scrotum.

signals from

and

On

for rare

when a markedly enlarged testis scrotal skin thickening is present), MHz transducer does not provide tissue

penetration,

and

color

occasions

a 5.0-MHz

is used.

.

supplies

erential

Doppler (eg,

or excessive the 7.5adequate transducer

size

testis

ANATOMY

these

noise.

the

containing

The testicular arteries are branches of the aorta that arise just distal to the renal arteries and descend in the retroperitoneum to enter the spermatic cord at the deep inguinal ring. Each testicular artery lies in the spermatic cord with the ipsilateral cremasteric artery (a branch of the inferior epigastric artery) and the deferential artery (a branch of the vesicular artery). Although there are anastomoses primarily

background

on

as a bar

of the testis and epididymis are obtained in all patients. Oblique longitudinal views through the vascular planes of the testis are then obtamed to optimally display the vessels. In all cases, the asymptomatic side should be used as a control for comparison.

between

of higher transmitted frepenetration. In our experifrequency of 7.5 MHz is between Doppler sensipenetration

depending

useful

in distin-

images

on the

and the amount of overlying skin thickening. Wall filters, if available, should be adjusted to the lowest possible value. Routine longitudinal and transverse views

There-

more

is displayed

flow. right

of the

frequency

are

to slow

of most

reflections.

probes

sensitivity

the red and blue color assignments ferent Doppler frequency shifts.

US unit

higher

amplitude

frequency

in detecting guishing

produce

higher

to maximize

side

(QAD-l ; Quantum Medical Systems, Issaquah, Wash) with a linear-array transducer. This transducer operates at 7.5 MHz for both imaging and Doppler analysis. The effect of trans. mitted frequency is very important. Because the Doppler frequency shift is proportional to the transmitted frequency and because the intensity of reflection from an object as small as an erythrocyte is proportional to the fourth power of the transmitted frequency, higher

frequency

value

find-

and

Doppler

is maximized

de-

should

on a towel placed All of our examinations

(threshold)

scale

technique.

scrotum

gain

sensitivity while avoiding excesnoise. If the threshold is too low, normal vessels will not be detected. The DoppIer scale (ie, the range of displayable Doppier frequency shifts) is decreased to its lowDoppler

TECHNIQUE

Color

Color

for optimal sive color

The

scribes our experience with normal testicular vascular anatomy, inflammatory disease of the scrotum, testicular torsion and ischemia, tumors, varicoceles, and trauma. It also describes

vessels.

est

the

surgical

This

In addition to selection of the proper transducer, several other adjustments must be made to optimize detection of the low-velocity, low-volume flow in the small testicular

and

epididymis, tissues

vessels, the

cremasteric vas

(7,8).

the

testicular

testis,

arteries

deferens,

Venous

artery

whereas and

outflow

the

supply

def-

the

peritesticular from

the

scro-

tum

is through the pampiniform plexus in the spermatic cord. This plexus drains into the ipsilateral testicular vein. The right testicular vein drains directly into the inferior vena cava while the left vein empties into the left renal vein.

The

veins

is shown

origin

of the

scrotal

in Figure

1.

arteries

and

The anatomy of the intrascrotal arteries is illustrated in Figure 2. After entering the scrotum, the testicular artery runs along the posterior aspect of the testis and penetrates the tunica albuginea to form capsular arteries that run just beneath the tunica albuginea in a

942

#{149} RadioGrapbics

#{149}Horstman

et al

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11

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R. Testiculor

L. Inferior Epigostric

Vein

-

Artery

la.

lb. 1, 2. Diagrams ply to the scrotum (la) from the scrotum (ib). Figures ‘O

Cremosteric

a.#{149}

intrascrotal

arterial

show

normal

arterial

sup-

and normal venous drainage (2) Diagram shows normal supply. a = artery, L = left, R =

right.

-

Recurrent

romi

2.

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Figures 3, 4. (3) Normal intratesticular vascular anatomy. (a) Longitudinal view of testis shows a capsular artery (straight arrows) along the lower pole and multiple centripetal arteries (curved arrows) entering the testis. The Doppler scale is to the right ofthe image. Frequency shifts between + 1,638 and -984 Hz are displayed. This is the smallest scale possible at this field ofview. (b) Longitudinal view of testis shows a centripetal artery (curved arrow) and several small recurrent rami (straight arrows) with blood flow in opposite directions. (c) Longitudinal view at the edge of the testis shows typical tortuosity of the smaller capsular arteries (arrow). (4) Transtesticular artery and vein. Transverse view of the testis shows two centripetal ies (CA) and a transtesticular artery (TA) with blood flow in opposite directions. A testicular vein (1V) companying the transtesticular artery. All vessels are oriented in a radial pattern toward the mediastinum (M), and the transtesticular vessels penetrate the mediastinum.

layer called the tunica vasculosa. The major capsular arteries are straight and are easily seen from multiple views. The smaller capsular arteries are tortuous and are usually seen on views that include only the edge of the testis. The capsular arteries have centripetal branches that enter the testicular parenchyma

944

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and flow approach arteries

toward the mediastinum. the mediastinum, the arborize

into

recurrent

arteris ac-

As they centripetal rami

that

branch back in the opposite direction (9). Capsular and centripetal arteries are visible in all normal adult testes (Fig 3). The recurrent rami may be too small to be visualized in some individuals. In most cases, no arteries flow through the mediastinum. However, in some men, the testicular artery has a large transtesticular

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Figure

5. Vascular planes of the testis. (a) Transverse view of the testis shows multiple centripetal arteries oriented radially toward the mediastinum (M). Line 1 represents a vascular plane; line 2 does not. (b) Longitudinal 1 in a) shows multiple

view

of a vascular

plane

elongated testicular (C) Longitudinal view outside the vascular (line 2 in a) shows vessels in cross section mizes the apparent vasculanity.

All intratesticular ented in vascular diastinum. The best appreciated testis.

vessels tend to be onplanes that intersect the meorientation of these planes is on transverse views of the

Longitudinal

views

obtained

in these

planes branch through from these Once

that enters the testis

the mediastinum in the opposite

and flows direction

the centripetal arteries. We refer to vessels as transtesticular arteries (Fig 4). these transtesticular arteries reach the

surface

of the

testis,

they

supply

capsular

ar-

teries that branch in a normal pattern. The testicular veins normally exit the mediastinum, but usually they are not visible with color Doppler US. However, when a transtesticular artery is present, it is often accompanied by a large vein that is visible (Fig 4). The above findings apply only to adults. Similar anatomic studies have not been performed in children and neonates. Because the pediatric testis and testicular vessels are smaller,

more

reliable

identification

of vessels

tend to accentuate the apparent lanity of the testes because the vessels elongated. Longitudinal views outside planes minimize the apparent testicular lanity

because

(line

arteries. plane and mini-

the

vessels

are

vascuare the vascu-

foreshortened

and

are seen in cross section (Fig 5). In this article, color Doppler US images used to illustrate the normal appearance of the testis were selected to show specific vascular anatomy. In most cases, obtaining these images

required

the precise plane could be displayed clinical

situations,

nor necessary, gree of detail.

additional

time

to determine

in which multiple simultaneously. it is generally

to show

vessels In routine not

vascularity

possible,

in this

de-

is

difficult.

November

1991

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Figure 6. Typical Doppler waveforms testicular lar vessels. V = vein.

and

pulsed from

peritesticu-

A

artery,

=

U HEMODYNAMICS As with other solid organs, the testis has a low vascular resistance. Therefore, the testicular artery and all of its capsular and intratesticuian branches are characterized by typical lowresistance waveforms with relatively broad systolic

peaks

and

Conversely, arteries

the supply

high

levels

of diastolic

cremastenic the

and

high-resistance

flow.

deferential vascular

beds of the epididymis and peritesticular tissues and therefore are characterized by narrower systolic peaks and lower levels of diastolic flow (9). Because these latter vessels are often sampled in the spermatic cord, waveforms from the supratesticular region may be either low resistance (testicular) or high resistance

resistance

(cremastenic

and

in an artery

deferential).

can

be estimated

Vascular

by

using the resistive index defined as (peak systolic velocity end-diastolic velocity) /peak systolic velocity. Higher resistive indexes indicate more resistance to flow. In 30 normal -

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testes, resistive indexes of supratesticular yessels were 0.63-1.00 (mean, 0.84). Resistive indexes from capsular vessels were 0.46-0.78 (mean, 0.66), and resistive indexes from intratesticular vessels (centnipetal and recurrent rami) were 0.48-0.75 (mean, 0.62) (9). Typical pulsed Doppler waveforms from various testicular and penitesticular vessels are illustrated in Figure 6. U

INFLAMMATORY

Epididymitis

and

DISEASE epididymo-orchitis

are

the

most common causes of acute scrotal pain, accounting for approximately 634,000 office visits per year. If not treated promptly, these infections can progress to abscess formation or testicular infarction. In cases of primary epididymitis,

associated

involvement

of the

testis is common. without epididymitis

However, isolated orchitis is uncommon and usually is viral or posttraumatic in origin (10,11). The main purpose of imaging in patients with presumed inflammatory disease is to distinguish inflammation from testicular torsion or other surgically treatable causes of scrotal

Volume

11

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6

‘

the lower

1.

(c) Pulsed

.h’#{149}

Longitudinal

(T) and

view

epididymis

of (E)

Doppler

waveform

ofepididymal

tail

shows abnormal low-resistance arterial flow (below baseline) and abnormal, detectable venous flow

:.

_#{149},..

#{149}#{149}h,g

(a)

of the testis

shows marked hypervasculanity of the epididymal tail. (b) Contralateral testis shows normal amount oftesticular (T) and epididymal (E) vasculanity.

.:#{149}

..

Epididymitis.

pole

(above baseline). from a contralateral

2 .

.

‘:1

(d) Pulsed Doppler waveform peritesticular artery shows

cal high-resistance pattern. (e) Radionuclide gram shows increased perfusion to the right scrotum, especially along its lateral margin.

typianglo-

hemi-

-, -,

‘‘l

-

1,

the normal epididymis demonstrates tectable flow (even at the lowest C.

pain,

such

as abscess

or

testicular

tumor.

In

these cases, color Doppler US can be helpful by providing both accurate morphologic data and information about testicular perfusion. The cardinal feature of inflammation is hyperemia, which is well displayed with color Doppler US as hypervasculanity (1). Because

November

1991

no depossible flow

settings), we believe that the detection of any epididymal vasculanity is abnormal and mdicates hyperemia (Fig 7). We recently reviewed 5 1 well-documented cases involving 45 patients with scrotal inflammation. In this group, it was always possible to demonstrate hypervasculanity of the inflamed epididymis or testis.

It was

not

uncommon

Horstman

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et a!

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Figures 8-10. (8) Epididymitis. Longitudinal view of the epididymal head (E) and upper pole of the testis shows normal size and echogenicity of the epididymis but multiple detectable vessels indicative of hyperemia. (9) Epididymo-orchitis. Transverse view of symptomatic testis shows marked diffuse hypervascularity. (10) Multifocal orchitis. (a) Longitudinal gray-scale US image of the testis shows multiple areas of decreased echogenicity. (b) Corresponding color Doppler US image shows hypervascularity within the hypoechoic regions.

scale

appearance

be normal, culanity cases,

of the

epididymis

or

despite readily evident (Fig 8). In approximately

epididymal

hypervasculanity

was

with sparing of the head or tail. Thus, tire organ should be examined before didymitis

is excluded.

Testicular

formation.

With

color

to

focal,

the enepi-

involvement

was usually diffuse (Fig 9) but was focal 10% of the cases (Fig 10). One complication of epididymo-orchitis abscess

testis

hypenvas25% of the

Doppler

in is US,

an

abscess will appear as a complex scrotal fluid collection with peripheral hypervascularity but no internal vessels (Figs 1 1, 12). Another complication is testicular ischemia, which occurs when epididymal edema compresses the venous outflow of the testis. This may be detected as diastolic flow reversal on intratesticular arterial waveforms (Fig 13). Theoretically, early testicular torsion with compromised venous outflow could also result in diastolic flow

reversal

with

epididymitis

vasculanity,

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and

with

However,

arteries. is epididymal

torsion

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11

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1_.). 11-13. (1 1) Intratesticular abscess. (a) Longitudinal view of the testis demonstrates an intratesticular fluid collection (FC) with low-level internal echoes, increased through transmission, and increased peripheral vasculanity. (b) Follow-up scan shows return to normal after 7 weeks of antibiotic Figures

therapy.

(12)

Pyocele.

(a) Longitudinal

view

of the

scrotum shows testicular atrophy (T) and complex scrotal fluid collection with peripheral hypervascularity; this was surgically proved to be a pyocele (P). (b) Delayed scintigram shows increased blood-pool activity pyocele activity

ischemia.

in the left hemiscrotum. Anteriorly has the appearance of relatively centrally. (13) Epididymitis with

Pulsed

Doppler

waveform

located

decreased testicular

from

intratesticu-

lan artery shows abnormal diastolic flow reversal resulting from decreased venous outflow caused by the epididymal swelling. This indicates increased risk of

ischemic

damage

to the testis.

13.

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b.

a

Figure

neous

14.

Acute

echogenicity

shows a normal after the injection (d) Intraoperative

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testicular

torsion.

but no detectable

(a)

Longitudinal

testicular

view

vasculanity.

of the

symptomatic

(b) Color

Doppler

testis

scan

shows

normal

of contralateral

homoge-

testis

number of intratesticular arteries seen on cross section. (c) Scintigram obtained immediately shows a photon-deficient area (arrow) corresponding to the position of the left testis. photograph shows a 360#{176} torsion of the spermatic cord and a congested, ischemic testis.

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Figure

15. Delayed torsion. (a) Transverse view shows decreased echogenicity of the intratesticular vessels. Marked penitesticular hypervasculanity and a small hydrocele are gram obtained immediately after the injection shows centrally decreased and peripherally in the left hemiscrotum.

Our scrotal is generally

experience

with

inflammatory not

color

disease necessary

Doppler indicates

to obtain

US of that

tender it

pulsed

Doppler waveforms to establish the diagnosis. However, when they are obtained, they frequently show a lowered arterial vascular resistance (resistive index < 0.5 for testicular anteries and < 0.7 for epididymal arteries) (Fig 7). Another occasional finding on pulsed Doppler waveforms is venous flow. Because current equipment is not sensitive enough to detect venous flow on waveforms obtained from patients without disease (except in transtesticular veins accompanying transtesticular arteries), we believe that detectable venous flow is further evidence of inflammation (Fig 7) (1). This may prove to be untrue when slow-flow sensitivity improves. U TESTICULAR TORSION Testicular torsion is a true surgical emergency, since testicular viability is inversely related to the duration of ischemia. In many cases, clinical evaluation is limited by the nonspecificity of the history and laboratory results and the difficulty in palpating an extremely

November

1991

testis.

US is very

In these

effective

testis (T) and no present. (b) Scintiincreased activity

patients,

colon

in helping

Doppler

to make

or ex-

dude the diagnosis of torsion (2-6). The most common color Doppler US finding with testicular torsion is the complete absence of detectable flow in the symptomatic testis

(Fig

guished

14).

This

from

the

hypenvascularity sionally,

can

be

normal

readily testis

distinand

from

of epididymo-onchitis.

one

on two

small

vessels

the Occa-

are

seen

the twisted side, whereas tude ofvessels is detected

the normal multion the contralateral

side.

becomes

With

time,

the

testis

hypo-

echoic on gray-scale images, and pentesticulan hypenemia develops and is seen with colon Doppler US (Fig 15). One potential tation

with

colon

tion

of an

episode

ous

detorsion

flow ischemic

may

Doppler

be

US is in the

of torsion occurs.

normal,

after

In such on there

limi-

detec-

spontane-

cases, may

on

blood be

post-

hyperemia.

Horstman

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Figure tery ings

16.

ately after spectively

.

Acute

180#{176} testicular torsion. (a) Transverse view of the contralateral testis showed the normal interpreted prospectively as acute testicular

(arrow). View were correctly

the injection as normal.

Comparison

and

Acute

shows

of Color

Doppler

in

Evaluation

Scintigraphy

Scrotal

no asymmetry,

the

a finding

study

acute went

scrotal imaging

of

Disorders

of 28

presenting

had

surgically

color

Doppler

proved

US helped

in all seven

make

100%),

whereas

scintigraphy

correct

diagnosis

in six

86%). color single

US than

false-negative

positive

diagnoses

the

connect

majority

make

(sensitivity, was less

the

with

scintigraphy.

finding

from

The

a scinti-

in a patient There were

of torsion

with

with a no falseeither

test

(specificity, 100%). Similar results have been obtained by Mevonach et al (12) with a canine model. Although both modalities had high accuracy

in demonstrating

the

cause

of scrotal

pain (colon Doppler US, 100%; scintigraphy, 96%), we believe that color Doppler US is more suitable because of its speed, cost advantage, and superior morphologic detail and

952

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prospectively

testis more

makes

and

retro-

interpretation

of both

difficult.

U TESTICULAR TUMORS Tumors of the testis are the solid malignancies in young

torsion;

helped

with

graphic study occurred 180#{176} torsion (Fig 16).

studies

(sensitivity,

cases variability

Interobserver Doppler

diatnic

underSeven pa-

testicular

cases

interpreted

with

pain (5). Each patient with both methods.

tients diagnosis

patients

incorrectly

because it does not require exposure to ionizing radiation. To date, these modalities have not been compared in pediatric patients. As mentioned previously, the smaller size and decreased blood flow in the neonatal and pe-

US

To determine the relative accuracy of color Doppler US and scintigraphy in the evaluation of acute scrotal disorders, especially acute torsion, we conducted a prospective doubleblind

of the testis shows a single small capsular arnumber of intratesticular arteries. The findtorsion. (b) Scintigram obtained immedi-

of testicular

tumors

most men. are

common The vast detected

mi-

tially at physical examination; sonography is used to confirm that the mass is in the testis, that it is not a benign cyst, and that contralatenal lesions are not present. We have found that the vascularity displayed with color Doppier US tends to be related to the size of the tumor (13). Tumors smaller than 1.5 cm in diameter are hypovascular in relation to normal testicular parenchyma (Fig 17), whereas tumors larger than 1 5 cm are hypervascular. The distribution ofvessels within the hypervascular tumors may be relatively normal (Fig 18a) or may be quite distorted (Fig 18b). Infiltrative tumors such as leukemia and lymphoma demonstrate hypervascularity with a relatively normal vascular distribution that may be indistinguishable from orchitis (Fig 19). In most cases, the clinical history and the gray-scale sonographic findings are sufficient .

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Figures 17-19. (17) Small testicular tumor. (a) Longitudinal view of the testis shows a 1-cm hypoechoic mass (M) in the upper pole, with no detectable vasculanity. (b) Intraoperative photograph of bivalved testis shows focal upper pole mass (M) that proved to be a seminoma. (18) Large testicular tumor. (a) Transverse view of the testis shows a hypervascular seminoma (S ) larger than 1.5 cm surrounded by normal testis (T) and with relatively normal distribution ofvessels. (b) Longitudinal view of a different patient with diffuse seminoma demonstrates increased lar pattern. (19)

of symptomatic normal pattern this

appearance

orchitis

November

1991

vascularity Leukemic

and distortion of the infiltration. Longitudinal

vascuview

testis shows increased vascuianity but a of vessels. Without the patient history, is indistinguishable

from

that

of diffuse

(cf Fig 10).

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-1

a. Figure 20. testis shows

(arrows) with

Varicocele. (a) Transverse view of the mildly prominent penitesticular veins

without

any detectable

incompetent

venous

flow.

valves,

(b) In patients

a Valsalva

maneu-

ver produces augmented retrograde flow as a result of increased intra-abdominal pressure. (c) Augmented venous flow is also demonstrated with the patient in the upright position.

to establish the diagnosis of tumor. Experience with color Doppler US is currently too limited to determine if it adds important information for patients with testicular tumors. At present, our impression is that colon Doppier US may be beneficial in a limited number of patients, since it might suggest other diagnoses when the gray-scale findings alone would suggest a tumor. U

VARICOCELES

Varicoceles

occur

when

the testicular veins flow and subsequent iform the

plexus. left

Approximately

side

incompetent

valves

allow retrograde venous dilatation of the pampin-

as a consequence

85%

occur

of the

on

drainage

of the left testicular vein into the left renal vein rather than the inferior vena cava (14). Varicoceles can cause scrotal pain and adversely affect fertility by disturbing spermato-

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in

genesis. Because small varicoceles are difficult to detect clinically, colon Doppler US can play an important role in the evaluation of scrotal venous morphology and flow characteristics (15). The major criterion for diagnosing vancoceles is the detection of dilated peritesticulan vascular structures that demonstrate augmented venous flow during the Valsalva maneuver. In our experience, the increased flow with the Valsalva maneuver is the most useful finding. It is also useful to examine the patient while he is supine and then upright to detect increased retrograde flow (Fig 20). Mild transient flow augmentation can be seen with the Valsalva maneuver in some individu-

Volume

11

Number

6

21b.

Figures 21, 22. (21a) Color Doppler US image of a patient at rest shows no venous flow in the spermatic

cord.

(2

ib) With

the

Valsalva

maneuver,

there is minimal transient retrograde venous flow detected. No vanicocele was seen at venography. (22) Testicular contusion after blunt trauma. Transverse view shows avascular hypoechoic mass displacing

intratesticular

vessels

peripherally.

A tumor

of this size should be hypervascuiar; therefore, a posttraumatic lesion was considered more likely. Instead of proceeding to orchiectomy, scrotal exploration and testicular biopsy were performed, and the mass proved to be a contusion with areas of necrosis.

testicular torsion by stimulating forceful contraction of the cremasteric muscles. Colon Doppler US can be very helpful in demonstrating the morphologic alterations caused by trauma and in excluding torsion. It can also be helpful in differentiating posttraumatic

als (Fig 21). This should not be confused with the more prolonged flow augmentation seen with small vanicoceles. The absolute sensitivity of color

Doppler

celes has not yet is clearly superior (15). U

in detecting

conditions

vanico-

been established; however, to a physical examination

it

TRAUMA

Trauma tion,

US

to the

scrotum

hemorrhage,

penitesticular

November

can

result

on contusion

structures.

1991

Trauma

from

tumors,

since

tumors

larger

than 1.5 cm are hypenvascular and hematomas and other posttraumatic conditions may be avascular (Fig 22). In most cases, the color Doppler US findings and the clinical history provide adequate information on which to base patient management.

in laceraof the

can

testis

or

cause

Horstman

Ct

a!

U

RadioGraphics

U

955

a. Figure 23. Inappropriate Doppler scale in patient with diffuse seminoma. (a) High Doppler scale (+ 9,833 to - 5,901 Hz) results in poor sensitivity and perhaps in an impression of hypovascularity. (b) With the Doppier scale set as low as possible (+2,458 to -1,475 Hz), sensitivity is improved and multiple abnormal tumor vessels are seen.

ymis,

U PITFALLS As mentioned earlier, there are several cal parameters that must be optimized tect the low-velocity, low-volume flow testicular

vessels.

The

effect

of the

technito dein small

Doppler

scale is shown in Figure 23. The apparent vasculanity of the testis varies, depending on whether images are obtained in or out of the vascular planes of the testis (Fig 5). One common imaging pitfall is color assignment to hydrocele fluid. This occurs when transducer motion produces flow patterns within

the

assignment This

pitfall

hydnocele. can can

In some

closely be

avoided

cal features of a hydrocele ages (Fig 24).

cases,

simulate by

noting

Visible

supratesticular

the

on gray-scale

venous

inflammation,

and

tected. Testicular

typi-

absence visible

im-

stnating

arteries

include

the

testicular, deferential, and cremastenic arteries. Visible intnatesticular arteries include the capsular; centripetal; and, in some cases, recurrent rami and transtesticular arteries. Arterial flow is not normally seen in the epidid-

vascular.

Horstman

Ct

a!

in

flow

appears

may

be

de-

as a complete in the number In postpubertal

of

Doppler US appears to be than scintigraphy in demon-

Large

tumors

and

orchitis

hypovascuare hypenmay

have

a similar appearance. Varicoceles demonstrate venous flow with the Valsalva maneuver or when the patient is standing. We believe that the use of color Doppler US will continue to expand, especially in the imaging of acute scrotal disorders. Color Dop-

ings

U

venous

torsion

US allows

and

rate diagnosis scrotal disorders

RadioGraphics

anywhere

torsion.

phology

U

seen

Tumors smaller than 1.5 cm are lan, and tumors larger than 1.5 cm

pier

956

is not

on marked decrease vessels in the testis.

patients, color more sensitive be reemphabe readily decord and tes-

flow

scrotum. The testicular and intratesticular arteries have low-vascular-resistance patterns. The penitesticular arteries have high-resistance flow patterns. Scrotal inflammatory lesions are seen as hypenvascularity of the epididymis or testis. The gray-scale examination can be normal, and the involvement can be focal. Arterial vascuiar resistance is generally decreased with

color

varicoceles.

U SUMMARY A few important points should sized. The arterial flow should tected in the normal spermatic tis.

this

and

the

are

absent

for

the

perfusion

evaluation

and

of both

enables

mor-

an accu-

in cases of the most common in which the gray-scale findor

nonspecific.

Volume

11

Number

6

Figure lating

ders,

24. Hydrocele a vascular mass

consistent

fluid flow. or vanicocele.

with

(a) Longitudinal (b) Gray-scale

view image

1.

2.

9.

sonography.

10.

11

Radiology

Lerner RM, Mevorach RA, Hulbert WC, Rabinowitz R. Color Doppler US in the evaluation ofacute scrotal disease. Radiology 1990;

12.

176:355-358. 4.

5.

Middleton WD, Melson GL. Testicular ischemia: color Doppler sonographic findings in five patients. AJR 1989; 152:1237-1239. Middleton WD, Siegel BA, Melson GL, Yates

CK, Andriole

GL.

prospective

and

testicular

7.

KniegerJN,

scrotal

disorders:

of color

Doppler

scmntigraphy.

177: 177-18

6.

Acute

comparison

Radiology

US

13.

14.

1990; 15.

1.

Wang

K, Mack

L.

Middleton

Color

Horstman WG, Middleton WD, Melson GL. Scrotal inflammatory disease: color Doppler US findings. Radiology 1991; 179:55-59. Burks DD, Markey BJ, Burkhard TK, Balsara ZN, Haluszka MM, Canning DA. Suspected testicular torsion and ischemia: evaluation

with color Doppler 1990; 175:815-821. 3.

assignment a fluid

superior collection

to the testis, simuwith angular bor-

a hydrocele.

REFERENCES

U

shows color demonstrates

Preliminary

evaluation of color Doppler imaging for investigation of intrascrotal pathology. J Urol 1990; 144:904-907. Harrison RG, Barkley AE. The distribution of the testicular artery (internal spermatic artery) to the human testis. BrJ Urol 1948;

.

WD,

Doppler

Thorne

ultrasound

DA, Meison

GL.

of the normal

tes-

tis.AJR 1989; 152:293-297. Mittenmeyer BT, Berger RE, Borsai AA. Epididymitis: a review of 610 cases. J Urol 1966; 95:390-398. Freton RC, Berger RE. Prostatitis and epididymitis. Urol Clin North Am 1984; 11:8394. Mevorach PA, Lerner RM, Greenspan BS, et al. Color Doppler ultrasound compared to radionuclide scanning of spermatic cord torsion in a canine model. J Urol 1991; 145:428432. Melson GL, Middleton WD. Color Doppler sonography of testicular tumors. Presented at the 90th American Roentgen Ray Society Meeting, Washington, DC, May 13-18, 1990. Greenberg SH. Vanicocele and male fertility. Fertil Steril 1977; 28:699-706. PetrosJA, Andriole GL, Middleton WD, Picus

DD.

Correlation

of testicular

color

Doppler

ultrasound, physical examination, and venography in the detection of leftvaricoceles in men with infertility. J Urol 1991; 145:785788.

2:57-66. 8.

Harrison

and

functional 282.

November

RG.

cremasteric

The

importance.

1991

distribution

arteries

of the vasal

to the testis J Anat

and their

1949; 83:267-

Horstman

et a!

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U

957