Diagnostic ultrasound ( PDFDrive )

CHAPTER 54 Pediatric Pelvic Sonography 1885
RT OV
ADNX
A TRV
B CX SAG
C
SAG RT OV
FIG. 54.24 Ectopic Pregnancy in Young Woman
With Pelvic Pain and Vaginal Bleeding. (A) Transverse
gray-scale image demonstrates a thick-walled
structure in the right adnexa adjacent to the right ovary.
(B) Sagittal gray-scale image shows complex free luid.
(C) Color Doppler sonographic imaging of the right
adnexa reveals a circular, thick-walled structure with
a “ring of ire.”
of the “ring of ire” sign, which consists of high-velocity, lowimpedance
low within the hyperechoic ring, may be another
useful inding. 69 However, this sign is nonspeciic and may be
seen surrounding a normal corpus luteal cyst. Hypotension or
overt shock suggests ruptured ectopic pregnancy. Although TVS
has greatly improved the diagnostic evaluation of suspected
ectopic pregnancy, TAS plays a complementary role by providing
a global view of the pelvis and abdominal contents. 70 β-hCG
measurements are essential for establishing the diagnosis. his
glycoprotein hormone begins to increase in a curvilinear fashion
early in pregnancy and continues to increase until approximately
9 to 11 weeks, when it normally reaches a plateau. he plateau
lasts for a few days and declines at 20 weeks. β-hCG level doubles
on an average of approximately 48 hours when the pregnancy
is normal. In the presence of an ectopic pregnancy, however,
serum β-hCG levels oten rise much more slowly, and a plateau
is reached early in the pregnancy. A less than 50% increase in
β-hCG level in a 48-hour period is almost always associated
with a nonviable pregnancy, whether intrauterine or
extrauterine. 71
Infection
Pelvic Inflammatory Disease
Pelvic inlammatory disease (PID) is an infection of the upper
genital tract, usually related to Neisseria gonorrhoeae or Chlamydia
trachomatis infection. he serious sequelae of this disease include
ectopic pregnancy, infertility, and chronic pelvic pain. Adolescent
females are in a higher-risk group, and thus PID should be
considered in sexually active females with pelvic pain. he
ascending infection may afect uterus, fallopian tubes, and ovaries,
causing endometritis, salpingitis, oophoritis, pelvic peritonitis,
and tubo-ovarian abscess.
In a study by Bulas of PID in adolescents, 72 anatomic detail
was improved with TVS compared with TAS. Transvaginal scans
showed new abnormalities in 71% of patients, and the level of
disease severity was changed in 33% of patients, which afected
treatment decisions in many of these patients.
Acutely, the pelvic sonogram may be normal. 70,73 In the
endometritis stage of PID, the uterus may be enlarged and
more hyperechoic, may contain a small amount of luid in
the endometrial canal, and may have indistinct margins. he
normal fallopian tube is usually not visualized on sonography.
As the infection ascends, however, the fallopian tubes become
thick walled and ill with purulent material 72 (Fig. 54.25). A
pyosalpinx is a dilated, occluded fallopian tube that contains
echogenic purulent luid. A residual hydrosalpinx is a tubular
or round structure with anechoic luid. Ovarian changes from
PID may include enlargement secondary to the production of
inlammatory exudate and edema and development of many
tiny cysts, which may represent small follicles or abscesses
(Fig. 54.26).