Assess adnexal lesions systematically with O-RADS US v2022 using morphology, solid components, papillary projections, and color score.
Apply the classification or measurement steps from this guide in an interactive tool.
O-RADS US was developed to describe ovarian and adnexal ultrasound findings using a shared lexicon, convert imaging features into a malignancy-risk category, and make management recommendations more consistent. Version 2022 clarified the scope of the system and several definitions, including the distinction between bilocular and multilocular cysts, acoustic shadowing in solid lesions, and management recommendations.
O-RADS recommendations provide clinical support for average-risk patients without acute symptoms. Management should be individualized in the setting of acute pain, suspected torsion, pregnancy, known malignancy, high genetic risk, or another specific clinical scenario.
Before entering the O-RADS algorithm, determine which of these three groups the image belongs to:
This distinction matters because classic benign lesions such as a typical hemorrhagic cyst, dermoid, or endometrioma do not enter the general morphology algorithm from the beginning when no atypical feature is present.
| Category | General meaning | Approximate malignancy risk |
|---|---|---|
| O-RADS 0 | Incomplete or technically inadequate examination | Not defined |
| O-RADS 1 | Normal or physiologic finding | 0% |
| O-RADS 2 | Almost certainly benign | <1% |
| O-RADS 3 | Low risk | 1%–<10% |
| O-RADS 4 | Intermediate risk | 10%–<50% |
| O-RADS 5 | High risk | ≥50% |
These risk ranges are not histopathologic diagnoses. They are risk estimates based on the lesion's imaging phenotype.
In O-RADS US v2022, a solid component is tissue that protrudes at least 3 mm into the cyst lumen from the wall or a septation. Blood products and dermoid contents are not considered solid tissue. A papillary projection is a subtype of solid component surrounded by fluid on three sides.
A solid or solid-appearing lesion is one in which approximately 80% or more of the lesion is solid. This distinction determines which branch of the algorithm uses features such as color score and acoustic shadowing.
One practical change in v2022 is the following terminology:
A cyst with a single smooth septation and a size under 10 cm may be classified as O-RADS 2 when the other criteria are met. Calling every septated cyst “multilocular” out of habit may lead to unnecessary category escalation.
In cystic lesions, smoothness is assessed using the inner wall and septations. In solid lesions, the outer contour is assessed. Apparent irregularity should not merely reflect the imaging angle. Use multiple planes and adequate magnification.
An irregular wall or septation, a solid component, and papillary projections are among the key features that increase malignancy risk.
O-RADS US grades intralesional vascularity on four levels:
This assessment depends on equipment settings. The color score is unreliable when the pulse repetition frequency, wall filter, or gain is inappropriate. Although identical settings may not be feasible in every case, Doppler technique must be optimized to demonstrate low-velocity flow.
Broad or diffuse acoustic shadowing in a solid lesion may support fibromatous content and is used in the v2022 algorithm as a feature that improves specificity. Edge-refraction artifact is not true shadowing. Confirm in more than one plane that the shadow originates broadly from the lesion.
When the appearance is typical, the following may fall within the classic benign group:
The word “typical” is essential. If there is a new solid component, definite internal vascularity, an irregular wall, or unexpected growth, do not leave the lesion under a classic benign label. Reassess it using the other lexicon descriptors.
Ascites and/or peritoneal nodules that cannot be explained by another benign or malignant cause may upgrade an associated O-RADS 3 or 4 lesion to O-RADS 5. Heart failure, cirrhosis, infection, and other causes must be considered. Ascites in a patient with a small O-RADS 1–2-appearing lesion does not automatically indicate ovarian malignancy.
Findings: In a premenopausal patient, a 6.2 cm smoothly marginated bilocular cystic lesion in the right ovary, without a solid component or internal vascularity.
Under v2022, this morphology is assessed as a smooth bilocular cyst. The final category and follow-up recommendation should be confirmed using the official management table, together with lesion size, menopausal status, and clinical context.
Example reporting language:
In the right ovary, there is a 62 mm bilocular cystic lesion with smooth inner walls, no solid component or papillary projection, and no internal vascularity on Doppler imaging. The morphology is low risk according to the O-RADS US v2022 lexicon. The category and follow-up recommendation have been assigned according to the patient's menopausal status and the current O-RADS management table.
Findings: An 8 cm unilocular cyst containing three papillary projections, with definite but not maximal vascularity within the papillary structures.
In a unilocular cyst, the number of papillary projections and their vascularity are major determinants of risk category. A lesion with fewer than four papillary projections may enter the O-RADS 4 branch depending on the other features; four or more papillary projections support a higher-risk category. The final classification must be checked against the official algorithm.
Whenever possible, an adnexal lesion report should explicitly document:
Reticular fibrin strands and a retracting clot with concave margins favor a hemorrhagic cyst. When uncertain, use Doppler and follow-up findings.
In v2022, two locules are called “bilocular”; three or more are “multilocular.”
Technically inadequate Doppler may produce a falsely low color score.
Edge refraction is not true broad or diffuse acoustic shadowing.
The category should be auditable. The report must contain the findings that led to it.
The follow-up approach for the same morphology may differ according to menopausal status.
O-RADS 3 is a low-risk category, with an estimated malignancy risk from 1% to less than 10%. Management depends on lesion type, size, menopausal status, and clinical context.
The morphological lexicon may be helpful, but management recommendations were designed for average-risk patients without acute symptoms. Emergencies such as torsion or rupture have separate clinical priority.
No. The systems are complementary but use different imaging features and risk models. Ultrasound is the first-line test for most patients, whereas MRI is a problem-solving method for selected indeterminate lesions.
This content is educational and is not patient-specific medical advice. Every phrase, template, classification result, and recommendation must be verified and adapted by a physician using the complete examination, clinical context, current guidelines, and institutional protocol.
Use the relevant RadPhrases calculator, then verify the result against the official guideline and the complete examination.
