1. Role of 3D ultrasound in ectopic
pregnancy.
“Catch me if u scan .”
Dr. Omneya Nagy Elmakhzangy
Special Fetal Care Unit
Ain Shams University

3. Ectopic pregnancies in a Caesarean
scar
• Implantation of a pregnancy within a Caesarean
fibrous tissue scar is considered to be the rarest
form of ectopic pregnancy and a life-threatening
condition.
• Since the clinical diagnosis of an early pregnancy
implanted in a previous Caesarean scar can be
very difficult, it may occasionally be delayed until
the uterus ruptures and the patient experiences
life threatening bleeding (Seow et al., 2000, 2004;
Weimin and Wenqing, 2002; Yang and Jeng, 2003; Maymon et
al., 2004)

4. • Diagnosis should be based on the pregnant patient’s
history and her clinical manifestations, such as
abdominal pain and any amount of bleeding (ranging
from spotting to a lifethreatening haemorrhage). The
most important investigation, however, is based on
sonographic and Doppler flow findings (Marchiole et al.,
2004).
• Generally, sonography can detect an enlargement of
the Caesarean scar in the lower segment and a mixed
mass or a clear gestational sac that is attached to it. A
very thin myometrium in a state of pre-rupture can
occasionally be visualized inbetween the bladder wall
and the gestational scar (Weimin and Wenqing, 2002,2000,
2004; Fylstra, 2002)).

5. • a discontinuity in the anterior wall of the
uterus being demonstrated on a sagittal view
of the uterus when the direction of the
ultrasound beam runs through the amniotic
sac (Vial et al., 2000)
• This criterion assists in distinguishing this type
of pregnancy from other diagnostic options,
such as cervicoisthmic implantation, cervical
pregnancy and spontaneous abortion in
progress (Godin et al., 1997; Fylstra, 2002)

6. • Others (Shih, 2004) used 3-dimensional (3D)
ultrasound and 3D Power Doppler. According
to their experience, using the combination of
the multiplanar views and 3D-rendered
images permits more accurate diagnosis in the
same situation.
• The peritrophoblastic flow surrounding the
trophoblastic shell may be further illustrated
by 3D Power Doppler ultrasound to ascertain
the diagnosis (Shih, 2004)

9. Interstitial pregnancy
• Interstitial ectopic pregnancy is defined as the ectopic
gestation developing in the uterine part of the fallopian
tube. It is a rare event constituting only 5% of all tubal
ectopic pregnancies and is associated with a high rate
of complications (Wood C, et al. 1992).
• Interstitial ectopic pregnancy is associated with a
higher risk of shock and hemoperitoneum than other
forms of ectopic pregnancy, as well as with a higher
risk of maternal mortality due to delayed diagnosis and
high vascularity of the myometrium.
• The condition is difficult to diagnose, both clinically
and sonographically

10. • The presence of an eccentrically located gestation sac
with incomplete or asymmetric myometrial tissue, < 5
mm in thickness, is a highly suggestive but nonspecific
indicator of interstitial pregnancy.
• The 3D scans are very useful in obtaining the coronal
scans of the fundal region of the uterus, giving a better
overview of the cornual regions of the uterus. The
characteristic features of an interstitial ectopic
pregnancy include a GS located eccentrically outside
the endometrial cavity of the uterus, in the region of
the fundus with no or minimal identifiable myometrial
tissue on its lateral aspect. This eccentric location and
superior and lateral myometrial stripes are better and
easily visualized on coronal scans generated through
3D TVS, an infrequent achievement with 2D scans.

12. Three-dimensional sonographic
diagnosis of ovarian pregnancy
• Among ectopic pregnancies, ovarian ones are
extremely rare. Sonographic diagnosis is feasible
although differential diagnosis from the more common
tubal location is difficult. (Ghi-et al , 2005)
• Owing to their similar sonographic appearance, even
distinction from an ipsilateral corpus luteum is not
straightforward.(Ghi-et al , 2005)
• Among the risk factors for ovarian pregnancy,
endometriosis or intrauterine device usage have been
commonly described (Riethmuller D. et al,1996)

13. Three-dimensional volume ultrasound
of the left ovary: a small mass
compatible with ‘bagel’ appearance
bulging from the cortex and co-existing
with two additional masses is noted.
CL, corpus luteum; ES, ectopic sac.
Appearance of left ovary at laparoscopy; a
small bleeding bulge on the ovarian
surface compatible with a gestational sac
is noted.
Copyright 2005 ISUOG