Diagnostic ultrasound ( PDFDrive )

554 PART II Abdominal and Pelvic Sonography
If an IUD is not seen on ultrasound and not known to have
been expelled, one should evaluate the adnexa sonographically
(Fig. 15.25G). However, if the IUD has perforated and is in the
pelvis, it might be diicult to identify sonographically owing to
bowel gas. A radiograph of the abdomen and pelvis should then
be done to determine if the IUD is present in the peritoneal
cavity.
Tubal Occlusion Devices
Tubal occlusion devices may be placed hysteroscopically into
the fallopian tube to provide permanent sterilization. he Essure
device (Bayer HealthCare Pharmaceuticals) has been most
frequently used. hese devices normally appear as curvilinear
hyperechoic structures in the cornual region bilaterally
(Fig. 15.25H–I). 186,187 Ideally the device spans the uterotubal
junction, extending slightly into the endometrial cavity and into
the fallopian tube. 188
he Adiana device (Hologic, Bedford, MA) is a nonabsorbable
silicone matrix that is inserted into the proximal fallopian tube.
he product has been discontinued, although one may still
encounter women with this device, which may appear as a small
hyperechoic area in the cornual region of the uterus. 189
POSTPARTUM FINDINGS
Normal Findings
he uterus will be enlarged initially ater delivery and usually
returns to its nongravid size by about 6 to 8 weeks ater delivery.
he uterus is oten sot and easily compressible by the transducer
during the irst few days ater delivery. TAS alone is oten adequate
to evaluate the uterus in the irst few postpartum weeks, as
the enlarged uterus usually provides an adequate sonographic
window. TVS is more oten needed later in the postpartum
period. he inner myometrium may be hyperechoic relative to
the outer myometrium in the early postpartum period and can
potentially be mistaken for the endometrium (Fig. 15.26A). 190
Echogenic foci due to air are normal and can persist for up
to 3 weeks. 191 Small amounts of luid and heterogeneous tissue
due to clot are commonly seen in the early postpartum period
(Fig. 15.26B).
Bleeding Postpartum
Some amount of bleeding postpartum is expected and is
normal; therefore visualization of blood and debris within
the postpartum uterus is a normal inding. When patients
have an abnormal amount of bleeding, pain, and/or fever,
then sonographic evaluation is typically used to assess for causes
such as retained products of conception (RPOC) or
endometritis.
Retained Products of Conception
At times the calciied appearance of the term placenta will be
visualized and the diagnosis of RPOC will be obvious. When
there is vascularized (based on detectable low on Doppler
imaging) tissue in the endometrial cavity (Fig. 15.27), this is
usually indicative of RPOC. If there is tissue that is not vascularized,
this could be due to either blood clot or devascularized
RPOC. he size of the suspected RPOC is important because
that may guide therapy. For example, at one of our institutions,
medical management is typically initiated for smaller regions of
RPOC (usually 2 cm or less) whereas D&C is typically performed
for larger areas which are felt to be unlikely to respond to medical
therapy. If RPOC are seen and they extend beyond the expected
endometrial cavity into myometrium, this is indicative of an
invasive placental condition such as placenta accreta. his is an
important diagnosis to suggest because the placenta will not be
easily removed at D&C and the patient will be at increased risk
A
B
FIG. 15.26 Normal Postpartum Findings. (A) Normal hyperechoic myometrium. Sagittal TAS image from a patient 4 days after vaginal delivery
shows hyperechoic appearance of inner portion of myometrium (between arrows). One could potentially misinterpret this entire area as endometrium.
(B) Normal endometrial luid. Sagittal TAS image from a patient 9 days after vaginal delivery shows a small amount of luid in the endometrial
cavity, a common inding in postpartum women.