is a radiologist with Radia Medical Imaging and the Medical
Director Medical Imaging at Providence Everett Medical Center,
Postmenopausal vaginal bleeding is a common clinical problem.
Postmenopausal bleeding (PMB) is caused by endometrial cancer in
approximately 10% of patients, although in some patient
populations, this percentage is as high as 30%.
Transvaginal sonography (TVS) along with endometrial biopsy (EMB)
have become the standards in the evaluation of patients with PMB. A
consensus conference sponsored by the Society of Radiologists in
Ultrasound (SRU) developed a complete, clinically useful algorithm
for the evaluation of patients with PMB beginning with EMB or with
The following case presentation illustrates the use of these
techniques to evaluate patients with PMB efficiently.
A 70-year-old woman who had been menopausal for 18 years
presented to her family physician with intermittent vaginal
spotting. She did not have a history of diabetes or obesity,
conditions which predispose women to endometrial cancer. She had
not been on hormone replacement therapy for several years. Her
family physician performed an EMB, which yielded tissue
insufficient for diagnosis.
She was then referred for ultrasound evaluation, which was
performed using Sequoia equipment (Acuson, Mountain View, CA).
Initially, a transabdominal scan was performed with a 4-MHz probe
with tissue harmonics. This showed a thickened endometrium
measuring 1.8 cm (Figure 1). Transvaginal scanning with an EC10C5
endoluminal probe demonstrated similar findings with the suggestion
of a small cystic space within the endometrium (Figure 2). Cystic
spaces can be seen with endometrial polyps. The radiologist,
recognizing the need to make a more definitive diagnosis in this
patient, suggested saline-infusion sonohysterography (SIS), which
was performed using a balloon catheter immediately following the
Following visualization of the cervix with a lighted speculum,
the catheter was inserted into the endometrial cavity.
Approximately 15 mL of sterile saline was instilled and gray-scale
and color Doppler images were obtained. The study showed a large
homogeneous soft-tissue mass in the endometrium with a relatively
thin attachment (Figure 3). Color Doppler evaluation of the mass
demonstrated a single central vessel (Figure 4), which was
diagnostic of an endometrial polyp. At hysteroscopy, a polyp was
discovered and removed successfully. There was no recurrence of the
A number of studies have been performed to define the role of
transvaginal ultrasonography and endometrial biopsy in patients
The results of studies have consistently shown that a
sonographically measured endometrial thickness of 5 mm or less
almost completely excludes endometrial carcinoma. In most of the
studies, endometrial biopsy was found to have a high sensitivity
for the detection of endometrial cancer, approaching 95% when there
was an adequate sample.
SIS has been shown to be useful for evaluating the endometrium,
particularly in patients with PMB. Even when the endometrial
thickness is 5 mm or less, SIS can identify an anatomic cause of
the bleeding accurately.
Postmenopausal vaginal bleeding is an important and common
problem. The data in older gynecology and radiology literature
suggest that anatomic reasons for bleeding are less common than
endometrial atrophy, which is a diagnosis made when no anatomic
cause is found.
More recently, however, the results of several studies indicate
that anatomic causes of PMB, such as polyps, leiomyomata, and
hyperplasia, are more common than had been previously thought.
Prior to the use of hysteroscopy, dilatation and curettage
(D&C) was the primary surgical diagnostic tool for PMB. Because
it is a blind procedure, D&C does not enable confirmation of
the presence of benign disorders, although it is excellent for
enabling the detection of endometrial carcinoma.
With the recent availability of hysteroscopy and SIS, more
benign anatomic abnormalities are being found in women with PMB.
Many of these abnormalities are polyps and fibroids, and these may
account for the abnormal bleeding. In a multicenter study
investigating the utility of SIS, Bree et al
reported polyps in 47%, leiomyomata in 11%, and endometrial
hyperplasia in 4% of women with PMB. Most of the remainder of the
patients in the study had a normal and thin endometrium, with a
single layer thickness of 2.5 mm or less. These patients probably
had endometrial atrophy as the etiology of the bleeding, although
that is currently a diagnosis of exclusion. Proving absence of
cancer and potential premalignant diagnoses, such as hyperplasia
and large polyps with atypia, is reassuring, and an important
benefit of performing SIS in these patients.
The SRU consensus panel on PMB was very useful in collating the
opinions and experience of a number of specialists in gynecology
and ultrasound on the appropriate evaluation of patients with PMB.
The panelists agreed that either TVS or EMB is an adequate
first-line test. Transabdominal sonography alone is not recommended
for this evaluation. A transvaginal sonogram can be called normal
only if the entire endo-metrium can be seen in a linear fashion
from fundus to cervix. The endometrium must be uniformly thin, and
measure 5 mm or less throughout its length. With a normal TVS or
normal and adequate EMB, further evaluation may not be necessary if
the presence or absence of cancer is the paramount issue. If either
TVS or EMB is inadequate or abnormal, but not obviously a cancer,
further testing with SIS, hysteroscopy, or D&C is warranted.
The choice of a follow-up examination is dependent on whether the
abnormality is focal or diffuse. Focal abnormalities will benefit
from SIS or hysteroscopy. With diffuse abnormalities, SIS is still
useful, but D&C alone may be able to make the correct
diagnosis. A minority of panelists thought that all women with PMB
should undergo SIS.
Bree et al
studied the accuracy and outcomes of using TVS and SIS in a series
of 98 patients with PMB. Using pathology and 6-month follow-up as
proof, the study resulted in a sensitivity of 98%, specificity of
88%, positive predictive value of 94%, and negative predictive
value of 97%. They showed that in a majority of cases, clinical
decision making and diagnostic confidence, as measured by a survey
of the treating physicians, was affected positively by the imaging
results. These decisions included confirmation of the treatment
decision already made, as well as change in management from
surgical to nonsurgical, and nonsurgical to surgical. In another
outcomes study evaluating cost-minimization algorithms for
different strategies for evaluating PMB, Medverd and Dubinsky
demonstrated that algorithms using ultrasound, including SIS, were
less expensive than those using biopsy and hysteroscopic
There are a number of diagnostic choices for evaluating patients
with PMB. Testing that begins with ultrasound seems to have the
best overall patient acceptance, accuracy, and lowest cost. In
patients who are at significant risk for endometrial cancer, it is
very appropriate to perform an EMB initially and, if positive, move
on to definitive therapy. Since cancer is seen in only
approximately 10% of patients with PMB, most other patients would
benefit from an approach using ultrasound. *