Abdominal and transvaginal ultrasound were performed in 18 patients,
while abdominal ultrasound alone was performed in the remaining 11 patients.
In most of them (27 cases) MRI was also performed.
The findings were confirmed by surgery and histopathology in 26 patients.
The remaining 3 had compatible findings on MRI.
A total of 44 endometriotic foci in different pelvic locations were identified (bladder,
ureter,
ovaries,
uterus,
rectovaginal septum,
retrocervical area,
rectovaginal pouch and bowel endometriosis).
The most frequent location was the posterior compartment of the pelvis: bowel endometriosis of the rectosigmoid junction was found in 11 cases (25%),
8 diagnosed with abdominal ultrasound and 3 with transvaginal ultrasound; and rectovaginal septum in 6 cases (13%),
all of them diagnosed with transvaginal ultrasound.
The second most frequent location was the central compartment (9 cases,
20%),
all diagnosed with transvaginal ultrasound.
Other locations included:endometriosis of ileum and cecal region (6 cases,
5 of them seen on abdominal ultrasound) and of the anterior compartment of the pelvis (urinary bladder and ureter,
all of them visualized with transvaginal ultrasound).
We were able to describe characteristic patterns in the bowel endometriosis of the rectosigmoid junction: pseudonodular morphology adhered to the serosa and bowel muscularis.
The margins were smooth or microlobulated,
with a marked thinning (pseudo tail sign) (Fig.
1A).
In this location,
the implants caused low retraction of adjacent structures.
Ileum and cecum endometriosis presented more frequently a laminar (plaque-like) morphology and spiculated margins that caused short stenoses (Fig.
1B).
We observed 4 cases in the bladder wall,
3 of them with nodular morphology and 1 with pseudonodular morphology with tail.
The implant located in the ureter,
with laminar morphology and spiculated margins,
caused severe hydronephrosis.
Laminar (plaque-like) morphology with retraction of adjacent structures was characteristic in the rectovaginal septum (Fig.
1C).
Nodular morphology often showed a heterogeneous echogenicity identifying small hypoechoic images inside (Fig.
1D).
In the literature,
different types of echogenicities of the endometriotic implant have been described: hypoechoic,
echogenic and heterogeneous.
In our series,
hypoechoic implants were the most common (21 cases).
The rest (8 cases) presented heterogeneous echogenicity.
Most of the patients presented endometriosis in other pelvic locations,
mainly ovarian endometriomas,
which facilitated the diagnosis.