Transcript ENCYSTED HEMATOCELE COMPLICATING CHRONIC ECTOPIC PREGNANCY

M ZEGHIDI1, Y MTAALAH1, F AMIRA1, C MBARK2, H OUESLATI2, S BOUSSETTA1
Department of Radiology1 and of gynecology2, Regional Hospital of Ben Arous
OB1
Chronic ectopic pregnancy is an unusual situation in
which the βhCG value can be low or negative.
Sonography could not disclose final diagnosis. If in
doubt, MRI is the investigation of choice for the
assessment of pelvic masses, particularly for extraovarian masses as hematocele.
We report the MRI features of five cases of chronic
ectopic pregnancy with encysted hematocele. The
mean overall age was 33 year-old.Their main
complaints consisted in meno-metrorrhagia, subacute
abdominal or pelvic pain. Pregnancy tests were
positive but low in four cases and negative in one case.
Intrauterine pregnancy was denied with transvaginal
sonography in all patients. Suprapubic and transvaginal
ultrasound revealed a large heterogeneous adnexal
mass in all the cases.
These patients underwent MRI in emergency. MRI was
performed using 1.5 T superconductive system (GE
system). Sagittal and axial + coronal T2-weighted
images, axial T1-weighted images with and without fat
saturation and axial T1 fat sat post contrast sequence
were performed.
MRI, which was performed to better characterizing
these adnexal masses, distinguished the different
components of these lesions. MRI illustrated
hematocele by assessing the location of this lesion, its
anatomic relationships, its morphology and its signal
characteristics.
We summarize our 5 cases in this table :
Cases
1
2
AGE
29
41
RISK
FACTOR
. Intrauterine
device
. Caesarean
section
SYMPTOMS
. Acute
abdominal
pain
. Vaginal
bleeding
Intra-uterine
Pelvic pain
device
B-HCG
(UI/I)
ULTRA SOUND
64
. An empty uterus
. A large heterogeneous
cystic mass with several
floating walls ranging
near to the pouch of
Douglas
322
. endometrial
decidualization with an
empty uterus
. A right adnexal solid
and cystic mass
3
4
5
29
35
30
Caesarean
section
Caesarean
section
Intrauterine
device
. Vaginal
bleeding
. Acute
abdominal
pain
Acute
abdominal
pain
Abdominal
pain
50
Negative
70
A mass with a dual
component near to
the right ovary
A heterogenous cystic
adnexal mass
. An empty Uterus
. Large heterogeneous
solid and cystic cystic
mass
endometrial
decidualization
with an empty
uterus
A solid and cystic right
adnexal mass
A large adnexal
complex cystic mass
with several floating
walls ranging near to
the pouch of Douglas
Hematocele exhibited a global central low signal intensity on T1
and T2 weighted images associated with a peripheral high signal
intensity on T1 image. These sequences demonstrated also a few
pseudo-nodular foci with high signal intensity on T1 and low signal
intensity on T2-weighted images suggesting hemorrhage with
different age of blood products.
Axial T2-weighted MR image shows masses of high and
medium signal intensity and axial T1-weighted MR image
shows the same masses with medium signal intensity
suggesting an encysted hematocele. Axial T1-weighted MR
image shows also a cystic GS with a yolk-like structure
surrounded by a thick wall. Post-contrast axial T1-weighted MR
image shows a sausage like structure with an enhancing wall
corresponding to the right fallopian tube that contains the GS
surrounded by the trophoblast.
Adnexal multilocular right
mass corresponding to a luteal
cyst + (central hyper T2,
peripheral hypo T1) on coronal
image, a hematocele (hyper
T2, hyper T1) and a
hematosalpix (heterogenous
signal on T1 and T2 images) on
sagittal sequences
+
An ectopic pregnancy is a clinical condition in which a fertilized
ovum implants in a area other than the uterine cavity. The most
common site for ectopic pregnancy is the fallopian tube. The
early diagnosis of ectopic pregnancy is based on the highly
sensitive human chorionic gonadotrophin (β-hCG) and
transvaginal sonography [1].
Chronic ectopic pregnancy is considered as a separate clinical
entity in witch a blood collection is organized.
This bleeding is spontaneously stopped by blood clots or
blocked by the omentum, the sigmoid colon and intestines
making a real diaphragm. Indeed, when the bleeding is scarce
(tubo-abdominal abortion, a cracked hematosalpinx), the blood
is confined to the lowest point of the peritoneal cavity, namely
the Douglas giving rise to a retro-uterine encysted hematocele
but also it can give rise to a latero-uterine or peri-tubal one.
The main strength of MR imaging is its ability to determine the
exact organ of origin when this hematocele is not clearly
determined by transvaginal US. This situation requires access to
MRI
in
emergencies
in
such
clinical
settings.
MR study is proposed to provide additional information for a
limited number of patients who need precise diagnosis.
MR imaging is capable not only of identifying blood but also of
determining the age of blood products as acute (intermediate
signal intensity on T1 and marked low signal intensity on T2),
subacute (peripheral high signal intensity with a distinct central
area of low intensity signal on T1 and T2) or chronic (entirely
high signal intensity on T1 and T2) [2].
MRI illustrates hematocele by assessing the location of
the lesion, its anatomic relationships, its morphology
and its signal characteristics (hypersignal T1/hypersignal
T2/non cleared after fat saturation in sequence FATSAT)
showing the hemorrhagic nature [3].
MRI also shows in some cases the abnormal gestational
sac and allows locating it precisely [4].
Although these examples shows the superiority of
MRI in comparison with ultrasound, specially in
better characterization of blood elements and good
anatomical definition), the sonographic appearance
should be known by the junior radiologists. So they
can suspect the diagnosis even if the clinical and
biological context is misleading.
In addition, MRI would be unnecessary if βhCG value
is positive.
MRI increased the diagnostic accuracy of chronic
ectopic pregnancy owing to its excellent tissue contrast
and spatial resolution.
1.Filhastre M, Dechaud H, Lesnik A, et al. Interstitial pregnancy : role of MRI.
Eur Radiol 2005; 15: 93-95.
2 . Kataoka ML, Togashi K, Kobayashi H, et al. Evaluation of ectopic pregnancy
by magnetic resonance imaging. Hum Reprod 1999; 14: 2644-50.
3. Yoshigi J, Yashiro N, Kinoshita T, et al. Diagnosis of ectopic pregnancy with
MRI: efficacy of T2*weighted imaging. Magn Reson Med Sci 2006; 5: 2532.
4. Kataoka ML, Togashi K, Kobayashi H, et al. Evaluation of ectopic pregnancy
by magnetic resonance imaging.Hum Reprod 1999; 14: 2644-50.