WELL Health Diagnostic Centres

O-RADS

O-RADS™ US v2022 — Assessment Categories

Release Date: November 2022

O-RADS ScoreRisk Category [IOTA Model]Lexicon DescriptorsManagement
Pre-menopausalPost-menopausal
0Incomplete Evaluation [N/A]Lesion features relevant for risk stratification cannot be accurately characterized due to technical factorsRepeat US study or MRI
1Normal Ovary [N/A]No ovarian lesionNone
Physiologic cyst: follicle (≤3 cm) or corpus luteum (typically ≤3 cm)
2Almost Certainly Benign [<1%]Simple cyst≤3 cmN/A (see follicle)None
>3 cm to 5 cmNoneFollow-up US in 12 months*
>5 cm but <10 cmFollow-up US in 12 months*
Unilocular, smooth, non–simple cyst (internal echoes and/or incomplete septations)≤3 cmNoneFollow-up US in 12 months*
Bilocular, smooth cyst>3 cm but <10 cmFollow-up US in 6 months*
Typical benign ovarian lesion (see “Classic Benign Lesions” table)<10 cmSee “Classic Benign Lesions” table for descriptors and management
Typical benign extraovarian lesion (see “Classic Benign Lesions” table)Any size
3Low Risk [1 – <10%]Typical benign ovarian lesion (see “Classic Benign Lesions” table), ≥10 cmImaging:

  • If not surgically excised, consider follow-up US within 6 months**

  • If solid, may consider US specialist (if available) or MRI (with O-RADS MRI score)†


Clinical: Gynecologist
Uni- or bilocular cyst, smooth, ≥10 cm
Unilocular cyst, irregular, any size
Multilocular cyst, smooth, <10 cm, CS <4
Solid lesion, ± shadowing, smooth, any size, CS = 1
Solid lesion, shadowing, smooth, any size, CS 2–3
4Intermediate Risk
[10 –<50%]
Bilocular cyst without solid component(s)Irregular, any size, any CSImaging:
Options include:

  • US specialist (if available) or

  • MRI (with O–RADS MRI score)† or

  • Per gyn–oncologist protocol


Clinical: Gynecologist with gyn–oncologist consultation or solely by gyn–oncologist
Multilocular cyst without solid component(s)Smooth, ≥10 cm, CS <4
Smooth, any size, CS 4
Irregular, any size, any CS
Unilocular cyst with solid component(s)<4 pps or solid component(s)
not considered a pp; any size
Bi- or multilocular cyst with solid component(s)Any size, CS 1–2
Solid lesion, non-shadowingSmooth, any size, CS 2–3
5High Risk [≥50%]Unilocular cyst, ≥4 pps, any size, any CS
Imaging: Per gyn-oncologist protocol
Clinical: Gyn-oncologist
Bi- or multilocular cyst with solid component(s), any size, CS 3–4
Solid lesion, ± shadowing, smooth, any size, CS 4
Solid lesion, irregular, any size, any CS
Ascites and/or peritoneal nodules††

GLOSSARY

Smooth and irregular: refer to inner walls/septation(s) for cystic lesions, and outer contour for solid lesions; irregular inner wall for cysts = <3 mm in heightSolid: excludes blood products and dermoid contents; solid lesion = ≥80% solid; solid component = protrudes ≥3 mm (height) into cyst lumen off wall or septation
Shadowing: must be diffuse or broad to qualify; excludes refractive artifactpp = papillary projection; subtype of solid component surrounded by fluid on 3 sides
CS = color score; degree of intralesional vascularity; 1 = none, 2 = minimal flow, 3 = moderate flow, 4 = very strong flowBilocular = 2 locules; multilocular = ≥3 locules; bilocular smooth cysts have a lower risk of malignancy, regardless of size or CS
Postmenopausal = ≥1 year amenorrhea (early: <5 yrs; late: ≥5 yrs); if uncertain or uterus surgically absent, use age >50 years (early = >50 yrs but <55 yrs, late = ≥55yrs)

*Shorter imaging follow-up may be considered in some scenarios (eg, clinical factors). If smaller (≥10–15% decrease in average linear dimension), no further surveillance. If stable, follow-up US at 24 months from initial exam. If enlarging (≥10–15% increase in average linear dimension), consider follow-up US at 12 and 24 months from initial exam, then management per gynecology. For changing morphology, reassess using lexicon descriptors. Clinical management with gynecology as needed.

**There is a paucity of evidence for defining the optimal duration or interval for imaging surveillance. Shorter follow-up may be considered in some scenarios (eg, clinical factors). If stable, follow-up at 12 and 24 months from initial exam, then as clinically indicated. For changing morphology, reassess using lexicon descriptors.

† MRI with contrast has higher specificity for solid lesions, and cystic lesions with solid component(s).

†† Not due to other malignant or non-malignant etiologies; specifically, must consider other etiologies of ascites in categories 1–2.

O-RADS™ US v2022 — Classic Benign Lesions

Release Date: November 2022

LesionDescriptors and Definitions

For any atypical features on initial or follow-up exam, use other lexicon descriptors
(eg, unilocular, multilocular, solid, etc.)
Management

If sonographic features are only suggestive, and overall assessment is uncertain, consider follow-up US within 3 months
Typical Hemorrhagic CystUnilocular cyst, no internal vascularity*, and at least one of the following:

.Reticular pattern (fine, thin intersecting lines representing fibrin strands)
.Retractile clot (intracystic component with straight, concave, or angular margins)
Imaging:

Premenopausal:
≤5 cm: None
>5 cm but <10 cm: Follow-up US in 2–3 months

Early postmenopausal (<5 years):
<10 cm, options to confirm include:
Follow-up US in 2–3 months or
US specialist (if available) or
MRI (with O–RADS MRI score)

Late postmenopausal (≥5 years):
Should not occur; recategorize using other lexicon descriptors.

Clinical: Gynecologist**
Typical Dermoid CystCystic lesion with ≤3 locules, no internal vascularity*, and at least one of the following:

.Hyperechoic component(s) (diffuse or regional) with shadowing
.Hyperechoic lines and dots
.Floating echogenic spherical structures
Imaging:

≤3 cm: May consider follow-up US in 12 months†

>3 cm but <10 cm: If not surgically excised, follow-up US in 12 months†

Clinical: Gynecologist**
Typical EndometriomaCystic lesion with ≤3 locules, no internal vascularity*, homogeneous low–level/ground glass echoes, and smooth inner walls/septation(s)

± Peripheral punctate echogenic foci in wall
Imaging:

Premenopausal:

<10 cm: If not surgically excised, follow-up US in 12 months†

Postmenopausal:

<10 cmand initial exam, options to confirm include

Follow–up US in 2–3 months or

US specialist (if available) or

MRI (with O-RADS MRI score)

Then, if not surgically excised, recommend follow-up US in 12 months†

Clinical: Gynecologist**
Typical Paraovarian CystSimple cyst separate from the ovaryImaging: None

Clinical: Gynecologist**
Typical Peritoneal Inclusion CystFluid collection with ovary at margin or suspended within that conforms to adjacent pelvic organs

± Septations (representing adhesions)
Imaging: None

Clinical: Gynecologist**
Typical HydrosalpinxAnechoic, fluid–filled tubular structure

± Incomplete septation(s) (representing folds)
± Endosalpingeal folds (short, round projections around inner walls)

*Excludes vascularity in walls or intervening septation(s)

**As needed for management of clinical issues

† There is a paucity of evidence for defining the need, optimal duration or interval of timing for surveillance. If stable, consider US follow-up at 24 months from initial exam, then as clinically indicated. Specifically, evidence does support an increased risk of malignancy in endometriomas following menopause and those present greater than 10 years.