Ultrasound of a 28-year-old woman with right-sided pelvic pain shows a right adnexal cyst with uniform low-level internal echoes ('ground glass' appearance) measuring 5 cm, no internal vascularity on Doppler, and no solid nodules. This appearance is most characteristic of:

• A Ovarian dermoid cyst
• B Mucinous cystadenoma
• C Ovarian fibroma
• D Endometrioma ✓

Explanation

An endometrioma (chocolate cyst) classically appears on ultrasound as a unilocular or multilocular cyst with homogeneous low-level internal echoes giving a ground-glass or 'chocolate' appearance, representing old hemorrhagic material. The absence of internal vascularity and solid nodules distinguishes it from malignancy. This pattern is so characteristic that it is considered diagnostic with high specificity. Dermoid cysts show a hyperechoic Rokitansky nodule, layering fat, and acoustic shadowing. Mucinous cystadenoma tends to be multiloculated with anechoic locules.

Reference: Grainger & Allison's Diagnostic Radiology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.