O-RADS Ultrasound (Adnexal Lesion Risk Stratification)

ACR O-RADS US v2022

Assigns an ACR O-RADS US (v2022) category 0-5 to an ovarian or adnexal lesion from its ultrasound descriptors, returning the associated malignancy risk band and management guidance.

Also searched as: adnexal mass · ovarian cyst · gynecology · ovarian · cyst

Is the examination technically adequate?

If technical factors prevent characterization, the exam is O-RADS 0.

What type of finding/lesion is present?

Classic benign lesion subtype

Required only for classic benign ovarian lesions.

Maximum lesion diameter

Largest diameter in any plane. Not used for cystic lesions with solid components or for solid lesions.

Lesion composition

A solid component is focal wall/septal thickening ≥3 mm in height; blood products and dermoid contents do not count as solid components.

Number of locules (chambers)

Internal content of a unilocular cyst

Inner wall / septation contour

Menopausal status

Papillary projections (unilocular cyst with solid component)

A papillary projection is a solid component surrounded by fluid on three sides.

Color Doppler score (IOTA 1-4)

Outer contour of a solid lesion

Broad or diffuse acoustic shadowing (solid lesions)

Refractive edge artifact does not qualify; shadowing only matters when the outer contour is smooth.

Ascites ± peritoneal nodules, not explained by another cause

Upgrades O-RADS 3-4 lesions to O-RADS 5; in O-RADS 1-2, seek an alternative explanation.

Information

Incomplete input

The following information is still needed: technical adequacy of the examination.

How this tool works

The Ovarian-Adnexal Reporting and Data System for ultrasound standardizes how adnexal lesions are described and stratified. Lesions are first separated into normal/physiologic findings, classic benign lesions (paraovarian cyst, hydrosalpinx, peritoneal inclusion cyst, hemorrhagic cyst, dermoid, endometrioma), and all other lesions. Other lesions are scored by composition: cystic lesions without a solid component use locularity, inner wall/septation contour, size, menopausal status, and color Doppler score; cystic lesions with a solid component use locularity with either papillary-projection count (unilocular) or color score (septated); solid lesions use outer contour, broad/diffuse acoustic shadowing, and color score. Unexplained ascites upgrades O-RADS 3-4 lesions to O-RADS 5. Each category 0-5 carries a defined malignancy risk range (<1% up to >=50%) with linked management recommendations.

References

Implemented from the cited published sources. Educational use only; confirm against current guidelines before clinical use.

Clinical questions that use this

Vetting guides that reach for this tool.

Related calculators

Same subspecialty, overlapping subject matter.

IOTA Simple Rules (Adnexal Mass)O-RADS MRI Risk Stratification (Adnexal Lesion)