Florio_subbed.qxp 30/4/09 10:56 Page 11
Non-invasive Tools for the Diagnosis of Endometriosis
Table 4: American Fertility Society Revised Classification System for Endometriosis*
Site Endometriosis Lesions <1cm (points) Lesions 1–3cm (points) Lesions >3cm (points)
Peritoneum Superficial 1 2 4
Deep 2 4 6
Right ovary Superficial 1 2 4
Deep 4 16 20
Left ovary Superficial 1 2 4
Deep 4 16 20
Posterior cul-de-sac obliteration: Partial obliteration: 4 points
Complete obliteration: 40 points
Site Adhesion Type Site <
1
⁄3 Enclosed (points) Site
1
⁄3–
2
⁄3 Enclosed (points) Site >
2
⁄3 Enclosed (points)
Right ovary Film 1 2 4
Dense 4 8 16
Left ovary Film 1 2 4
Dense 4 8 16
Right tube Film 1 2 4
Dense 4 8 16
Left tube Film 1 2 4
Dense 4 8 16
*Stage of endometriois is determined by the total number of points assigned to endometriotic lesions and adhesions: stage I (minimal) = 1–5 points; stage II (mild) = 6–15 points;
stage III (moderate) = 16–40 points; stage IV (severe) = >40 points.
Imaging Studies in the Figure 1: Schematic Representation of
Diagnosis of Endometriosis
Endometriosis Classification
Endometriosis is a heterogeneous disease spanning a spectrum from
minimal disease (stage I, characterised by small 1–5mm implants on
Stage I, minimal Stage II, mild
the pelvic peritoneum) to severe disease (stage IV, characterised by
obliteration of the cul-de-sac, deep ovarian endometriosis cysts and
major pelvic adhesions)
48
(see Table 4 and Figure 1). Endometriomas
are relatively common and can mimic other adnexal masses.
Transvaginal ultrasound (TVU) is the method of choice to identify
endometriomas corresponding to a benign ovarian neoplasm
persisting after three months. Ultrasound findings suggestive of an
Stage III, moderate Stage IV, severe
endometrioma include homogeneous low- to medium-level echoes in
a thick-walled cystic mass (unilocular or multilocular). The positive
predictive value of sonography to predict endometriosis was evaluated
at 75% when criteria such as diffuse low-level internal echoes and
absent neoplastic features were used.
49
Differential diagnoses include
corpus luteum, teratoma, cystadenoma, fibroma, tubo-ovarian
abscess and carcinoma. Repeated ultrasound is highly recommended
Source: American Society for Reproductive Medicine.
for unilocular cysts with low-level internal echoes to differentiate
functional corpus luteum from endometriomas.
50
However, (MRI) also fails to detect subtle endometriotic lesions, although fat-
ultrasonography is of limited value for diagnosis or for determining the saturated MRI improves the detection rate of small haemorrhagic
extent of endometriosis since it lacks adequate resolution for lesions that measure less than 5mm from 4% with conventional MRI
visualising adhesions and superficial peritoneal/ovarian implants.
49,50
to 50%.
54
Current imaging technology does not permit reliable
assessment or classification of endometriotic adhesions.
Whether the addition of colour Doppler studies adds to the diagnostic
efficiency of TVU remains uncertain: while Alcazar et al.
51
found no With respect to the role of MRI for the diagnosis of ovarian
improvement in the performance of ultrasound in the diagnosis of endometrioma, it was reported that MRI features are almost
endometriomas by including colour Doppler, Aleem et al.
52
concluded exclusively based on the detection of chronic or recurrent bleeding
that scattered vascularity is typical of ovarian endometriomas and in the endometrioma. Larger endometriomas (>1cm) appear as a
distinct from the dense vascularisation associated with corpus homogeneously high-signal-intensity mass on T
1
-weighted
luteum cysts and ovarian neoplasms. Similar observations were made images and as a low-signal-intensity mass with focal high-signal-
by Guerriero et al.,
53
who reported that endometriomas are associated intensity areas on T
2
-weighted images.
55
In the presence of recent
with ‘poor’ blood supply whereas non-endometriomas are bleeding, the cyst content has high signal intensity in both types of
characterised by ‘rich’ vascularisation or the presence of arterial flow sequence. Finally, it has been suggested that transvaginal
in the papillary structures or echogenic areas of the cyst. sonogram (TVS) is useful in the diagnosis of ovarian endometriomas
if the diameter is ≥20mm; as TVS costs less than MRI, the
Superficial peritoneal endometriosis and ovarian surface implants ultrasonographic technique may be the preferred method of
are not detectable by ultrasound. Magnetic resonance imaging confirming a sizeable endometrioma.
56
EUROPEAN OBSTETRICS & GYNAECOLOGY 11
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84