Ultrasonographic Characteristics of Endometriomas

Classic Ultrasonographic Features

The American College of Radiology recommends that an endometrioma should be reported describing its characteristic appearance of homogeneous low-level internal echoes, presence of surrounding ovarian parenchyma, posterior acoustic enhancement, absence of internal flow on Doppler, and any additional characteristics such as multiloculation or peripheral echogenic foci 1, 2, 3
The presence of surrounding ovarian parenchyma is essential to confirm the ovarian origin of the lesion, as stated by the American College of Radiology 1, 2
Posterior acoustic enhancement is present due to the liquid content of the lesion, according to the American College of Radiology 1, 2, 3
The absence of internal flow on Doppler color is a characteristic feature of endometriomas, and any flow should raise suspicion of neoplasia, as recommended by the Journal of the American College of Radiology 1, 2, 3, 4

Multiloculation, when present, should be reported, and each loculation should show homogeneous low-level echoes, with possible flow in the intervening septa, as stated by the American College of Radiology 1, 2, 3
Peripheral echogenic foci, occasionally visible in the wall, should be reported, although they usually do not produce acoustic shadowing, according to the American College of Radiology 1, 2, 3

The American College of Radiology recommends a combined transvaginal and transabdominal ultrasound approach, which provides higher spatial resolution and contrast, as well as a general anatomical view 4, 5
Doppler color and spectral evaluation is essential to confirm the absence of internal vascularization and differentiate from neoplasias, as stated by the Journal of the American College of Radiology 1, 2, 3, 4

The American College of Radiology states that typical endometriomas with all classic characteristics and absence of internal flow generally correspond to low-risk lesions in the O-RADS system 1, 2, 3
Any atypical feature, such as significant internal vascularization, solid components with flow, or marked irregularity, should raise the risk category and consider additional evaluation with magnetic resonance imaging or consultation with a specialist, as recommended by the Journal of the American College of Radiology 1, 2, 3, 4

The American College of Radiology recommends that an endometrioma should be reported by describing essential characteristics, including homogeneous low-level internal echoes, creating a "ground glass" appearance of the cystic content, with a maximum lesion diameter that should be documented in centimeters, and characteristics that suggest malignancy, such as diameter >5 cm, thick or irregular septa, mural nodules, solid or papillary components 6, 7
Foci of peripheral echogenicity, occasionally visible in the wall, are usually deposits of hemosiderin, although they typically do not produce acoustic shadowing, according to the Journal of the American College of Radiology 8

Ultrasonography correctly characterizes 80% of endometriomas in patient series, with the use of Doppler color helping to avoid classifying malignancies as endometriomas by defining the presence of vascular flow in papillae 6, 7
The sign of uterine sliding is useful for evaluating adhesions and obliteration of the Douglas pouch, and evaluation of ovarian mobility helps identify associated adhesions, as per the Journal of the American College of Radiology 8