USMLE Prep - Medical Reference Library

O‑RADS — Ovarian/Adnexal US Risk Stratification

System: Radiology • Reviewed: Aug 31, 2025 • Step 1Step 2Step 3

Synopsis:

O‑RADS US categorizes adnexal masses by malignancy risk to guide follow‑up and referral to gynecologic oncology when indicated.

Key Points

  • Stabilize ABCs; begin targeted evaluation without delaying life-saving therapy.
  • Use system-specific risk tools to guide testing and disposition.
  • Order high-yield tests first; escalate imaging when indicated.
  • Start evidence-based initial therapy and reassess frequently.

Algorithm

  1. Primary survey and vitals; IV access and monitors.
  2. Focused history/physical; identify red flags and likely etiologies.
  3. Order system-appropriate labs and imaging (see Investigations).
  4. Initiate guideline-based empiric therapy (see Pharmacology).
  5. Reassess response; arrange consultation and definitive management.

Clinical Synopsis & Reasoning

For O Rads Ovarian Adnexal Us Risk Stratification, frame the differential by acuity and pathophysiology, then align diagnostics to the leading hypotheses. Prioritize stabilization while obtaining high‑yield studies such as CBC (Baseline hematology), BMP (Electrolytes/renal). Incorporate bedside imaging and targeted labs to define severity and identify complications; synthesize results with clinical trajectory to refine the working diagnosis and disposition needs.


Treatment Strategy & Disposition

Initiate disease‑directed therapy alongside supportive care, titrating to objective response. Pharmacologic options commonly include Analgesia/Antipyretics. Use validated frameworks (e.g., O‑RADS Snapshot) to guide escalation and site of care. Address precipitating factors, de‑escalate empiric therapies with data, and arrange follow‑up for monitoring and risk‑factor modification; admit patients with instability, high risk of deterioration, or needs for close monitoring.


Management Notes

Minimize ambiguity—use the O‑RADS lexicon verbatim. Provide images and measurements in multiple planes.


Epidemiology / Risk Factors

  • Risk factors vary by condition and patient profile

Investigations

TestRole / RationaleTypical FindingsNotes
CBCBaseline hematologyAbnormal counts
BMPElectrolytes/renalDerangements

O‑RADS Snapshot

CategoryManagement
2Routine follow‑up or none (simple cysts)
3Short‑interval follow‑up
4MRI or surgical evaluation
5Oncology referral
ModifiersMenopausal status, size

Pharmacology

MedicationMechanismOnsetRole in TherapyLimitations
Tranexamic acidAntifibrinolyticHoursHeavy uterine bleedingThrombosis risk
High-dose combined OCP or ProgestinHormonal therapyDaysBleeding controlVTE risk

Prognosis / Complications

  • Prognosis depends on severity, comorbidities, and timeliness of care

Patient Education / Counseling

  • Explain red flags and when to seek emergent care.
  • Reinforce medication adherence and follow-up plan.

References

  1. ACR O‑RADS US — Link