Ultrasound of Endometrioma

In this radiology lecture, we review the ultrasound appearance of endometrioma through three unique cases, including an MRI example.

Key teaching points include:

Endometriosis = Ectopic endometrial glands and stroma outside of the uterine cavity. Includes endometriomas, extraovarian implants and adhesions.
Endometriomas = Endometriotic cysts within ovary.
Endometriosis is seen in about 10% of women of reproductive age.
Presentation: Pelvic pain, dysmenorrhea, dyspareunia, infertility.
Ultrasound: Diffuse, homogeneous low-level echoes (most specific feature) yielding a ground glass appearance. May have posterior acoustic enhancement.
Endometriomas may have peripheral punctate echogenic foci. These foci have no internal vascular flow but can see twinkle artifact.
Vascular flow may be present in endometrioma septations.
Endometrioma vs. hemorrhagic cyst: Hemorrhagic cysts are acute, usually solitary and unilocular, whereas endometriomas are chronic, sometimes multiple and multilocular.
Endometriomas can rarely (1%) undergo malignant transformation into endometrioid carcinoma or clear cell carcinoma.
MR is the most specific imaging modality for diagnosis of endometrioma = Specificity 98%.*
Homogeneous, T1 “light bulb” bright, T2 dark = “T2 shading.”
Surgical treatment: Depends on disease severity from laparoscopic cyst aspiration/cystectomy to hysterectomy/oophorectomy.
Medical management may be attempted: Oral contraceptives, GnRH agonists