Diagnostic ultrasound ( PDFDrive )

CHAPTER 22 The Scrotum 833
A
B
FIG. 22.15 Adrenal Rests in Patient With Congenital Adrenal Hyperplasia. (A) Longitudinal scan shows multifocal hypoechoic masses
(arrows) within the testis that cannot be distinguished from tumor. (B) CT in same patient shows bilateral adrenal hyperplasia (arrows).
of circulating adrenocorticotropic hormone in CAH and Cushing
syndrome. hese lesions are typically multifocal, bilateral, and
eccentrically located. Sonographically, they are variable in appearance,
typically presenting as hypoechoic masses, although they
may be heterogeneous, hyperechoic masses with posterior acoustic
shadowing (Fig. 22.15). Adrenal rests can demonstrate spokelike
vascularity with multiple peripheral vessels radiating toward a
central point within the mass. Usually, if the patient has the
appropriate hormonal abnormalities associated with CAH and
if sonography shows the appropriate indings, no further workup
is necessary. 106,107 If conirmation of the diagnosis is required, a
biopsy under ultrasound guidance may be obtained intraoperatively
when the testis is exposed. Additionally, testicular vein
sampling will show elevated cortisol levels compared with
peripheral blood levels. 108 Treatment with glucocorticoid replacement
therapy results in stabilization or regression of
the masses. 109
Splenogonadal Fusion
Splenogonadal fusion is a rare congenital anomaly in which there
is fusion of the spleen and gonad. It typically occurs on the let
side and is most oten associated with cryptorchidism. 110 here
are two types of splenogonadal fusion: continuous and discontinuous.
In the more common continuous form, the gonad is linked
to the spleen by a ibrous cord of splenic tissue. In the discontinuous
form, ectopic splenic tissue is attached to the testis. Rarely,
ectopic splenic tissue may occur on the epididymis or spermatic
cord. Splenogonadal fusion may mimic testicular malignancy.
he diagnosis may be established by documenting uptake on a
technetium-99m sulfur colloid scan.
Calciications
Scrotal calciications may be seen within the parenchyma of the
testis or epididymis, attached to the tunica, or freely located in
the luid between the layers of the tunica vaginalis. Large, smooth,
curvilinear intratesticular calciications without an associated
sot tissue mass are characteristic of a large-cell calcifying Sertoli
cell tumor 111 (see Fig. 22.9C). Scattered calciications may be
found in tuberculosis, ilariasis, and scarring from regressed
germ cell tumor or trauma.
Scrotal Calciications
TESTICULAR
Solitary, postinlammatory granulomatous, vascular
Microlithiasis
Regressed, or “burned-out,” germ cell tumor
Large-cell calcifying Sertoli cell tumor
Teratoma
Mixed germ cell tumor
Sarcoid
Tuberculosis
Chronic infarct
Posttraumatic
EXTRATESTICULAR
Tunica vaginalis, “scrotal pearls”
Torsed appendages
Chronic epididymitis
Schistosomiasis
Testicular microlithiasis is a condition in which calciications
are present within the seminiferous tubules of the testis either
unilaterally or bilaterally. It is postulated that microlithiasis is
caused by defective Sertoli cell phagocytosis of degenerating
tubular cells, which then calcify within the seminiferous
tubules. 112,113 Microlithiasis has been classiied as difuse and
limited. 114 In the difuse form, innumerable small, hyperechoic
foci are difusely scattered throughout the testicular parenchyma.
hese tiny (1-3 mm) foci rarely shadow and occasionally demonstrate
a comet-tail appearance (Fig. 22.16). In the limited
form, less than ive hyperechoic foci are seen per image of the
testis (Fig. 22.16B).
Microlithiasis is seen in 1% to 2% of patients referred for
testicular sonography and has a reported prevalence in the general
population of 0.6% to 0.9%. 115 Microlithiasis has been associated
with cryptorchidism, Klinefelter syndrome, Down syndrome,
pulmonary alveolar microlithiasis, AIDS, neuroibromatosis,
previous radiotherapy, and subfertility. 112,115-117 Microlithiasis
is typically an incidental inding on scrotal ultrasound, and if