Detection of uterine abnormalities has been the focus of recent research in gynaecology. Structural
pathologies in the uterine cavity such as müllerian
duct anomalies (MDAs) and intrauterine lesions (fibroids, polyps, synechiae) may have an important
role in subinfertility, implantation failure and pregnancy outcome. As a result, screening for uterine
abnormalities is a part of routine clinical investigations of women who have histories of infertility,
recurrent miscarriages and early preterm labor (
There are two methods for three dimensional volume acquisition: the freehand technique and automatic acquisition. With the freehand technique,
images are obtained manually with the use of a two
dimensional transducer. Decreased accuracy of
measurements and less quality of images are two
possible problems when comparing the freehand
technique with the automated technique (
We obtained the images in this pictorial review with the use of an ACCUVIX XQ, (Medison, Korea) and three-dimensional transvaginal 3D5-8EK probes. This system employs a newly introduced technique named 3DXI, which utilizes two modes: multi-slice view and oblique view.
The multi-slice view transforms three dimensional volume data obtained from a regular ultrasound scan into a series of sequential images captured at intervals of 0.5 mm to 5 mm segments. Users can instantly view, analyze and understand the more in depth data, and thereby gain greater confidence and accuracy.
The oblique view enables the operator to examine and view three dimensional volume data in various planes of view. The exact portion of three dimensional data that the operator wants to visualize can be selected, thus allowing for a more complete visual examination and better understanding of the correlation between organs and other areas within the region of interest.
MDAs are relatively common disorders associated
with adverse reproductive outcomes. Critical analyses
of studies suggest that the prevalence of uterine
malformation in woman with repeated pregnancy
loss is about 3% (
Several classification systems describe MDAs.
The most accepted system is the American Fertility
Society (AFS) classification system (
Classification system of Müllerian duct anomalies developed by the AFS.
According to AFS, class I consists of hypoplasia
and agenesis. Class II represents unicornuate uterus.
Categories III and IV are composed of uterus
didelphys and bicornuate uteri. Categories V, VI
and VII refer to septate uterus, arcuate uterus and
diethylstilbestrol exposure, respectively (
Various imaging modalities have been used to evaluate MDAs. Despite being invasive, hysteroscopy and laparoscopy are the conventional methods for assessing uterine morphology.
HSG is one of the first conventional diagnostic tools
to provide valuable information about the uterine
cavity and tubal patency; however, the diagnostic
accuracy of hysterosalpingography (HSG) alone is
only 55% in the differentiation of septate from bicornuate
Technologic advances in imaging modalities have revolutionized the evaluation of MDAs by noninvasive tools such as 2DUS, 3DUS and magnetic resonance imaging (MRI).
Even though two dimensional sonography is routinely
used because of its flexibility and moderate
cost, it has some limitations. The sensitivity of
2DUS, particularly for the demonstration of fundal
contour is relatively low compared with other
Despite the high accuracy of MRI in appraising
the cervix and vagina, some limitations may favor
the use of 3DUS. MRI is highly operator and technique
dependent, and costly. The most important
advantages of real time 3DUS over MRI are lower
cost, shorter examination time and wider availability
3DUS images are easier to interpret in the luteal
phase of the cycle due to increased thickness and
echogenicity of the endometrium (
Although fluid instillation into the endometrial cavity enhanced endometrial visualization during transvaginal ultrasound, intrauterine lesions (e.g., polyps, fibroids and synechiae) can be diagnosed sonographically in the initial investigation without the need for fluid instillation. Using 3DUS facilitates access to the most relevant plane, and ability to visualize both the endometrium and the myometrium facilitates correct diagnosis of uterine abnormalities.
3DUS affords a more comprehensive understanding of exact the numbers, sizes and locations of intrauterine lesions. Fibroids causing uterine distortion are the most common uterine abnormalities associated with subinfertility, implantation failure and miscarriage. One of the most useful views obtained on 3DUS are views that enable a clear estimation of the relationship between the endometrium and intramural fibroids, and consider whether they distort the uterine anatomy or not.
Intrauterine adhesions have a variable appearance, ranging from small echogenic areas of focal endometrial thickening to an obliterated endometrium as in Asherman’s syndrome.
Comparison of three-dimensional ultrasound and HSG imaging in cases of uterine malformation using AFS: A. Normal uterus, B. Unicornuate uterus, C. Arcuate uterus, D-G. Different subtypes of septate uterus (partial to complete septum), H. Bicornuate uterus, I. Didelphys.
Endometrial polyps appear as persistent hyperechogenic
areas with variable cystic spaces and
distortion of endometrial contours. They are best
visualized during the mid-cycle and not readily
seen during the mid-luteal scan cycle when the endometrial
layer is thick (
Comparison of three-dimensional ultrasound and HSG imaging in cases of intrauterine lesions: A. Obliteration of the uterine cavity due to severe synechiae, B. Moderately extensive synechiae involving ½ of the uterine cavity, C. Endometrial polyp in the fundal area, D. Marked distortion and deformity of the uterine cavity caused by an intramural myoma bulging to the cavity.
3DUS, which has the ability to visualize surfaces three
dimensionally, has recently become available for endometrial
volume measurement. Ultrasonographic
assessment of the endometrium is an important investigative
tool in the assessment of endometrial receptivity.
Endometrial volume is a useful criterion in predicting
embryo implantation success and pregnancy rate
in patients undergoing
Volume estimation of the endometrium is easily
made because of good contrast between endometrial
tissue and myometrium. 3DUS allows us to
calculate the endometrial volume by manual delineation
of the endometrium (
Three dimensional volume calculation of endometrium in multiplanar display.
Endovaginal 3DUS is a non-invasive, outpatient diagnostic modality which enables a detailed assessment of uterine morphology and is superior to other techniques used for the same purpose. Because of the high level of agreement between 3DUS and hysterosalpingography, MRI, hysteroscopy and laparoscopy, therefore 3DUS has recently become the only mandatory step in the initial investigation of MDA and intrauterine lesions to assess whether hysteroscopic evaluation of the endometrial cavity is indicated.