Ovarian-Adnexal Reporting and Data System (O-RADS)

The Ovarian-Adnexal Imaging Reporting and Data System, (O-RADS), aims to ensure that there are uniform unambiguous sonographic and MRI evaluations of ovarian or other adnexal lesions, accurately assigning each lesion to a risk category of malignancy being present, and which informs the appropriate management that could be instituted. 

For risk stratification, the O-RADS system recommends six categories (O-RADS 0–5), incorporating the range of normal to high risk of malignancy. 

The Ovarian-Adnexal Reporting and Data System includes the following:

• O-RADS ultrasound
  • lexicon ¹
  • risk stratification score ²
  • calculator³
• O-RADS MRI
  • lexicon ⁴
  • risk stratification score ⁵
  • calculator⁶

The reporting system advocated by O-RADS includes a standardized lexicon that provides a uniform language for describing the imaging characteristics of adnexal lesions. 

History and etymology

O-RADS was developed by an international multidisciplinary committee, comprising clinicians and researchers from the fields of radiology, gynecology, pathology, and gynecologic oncology, and sponsored by the American College of Radiology (ACR). It was originally designed for sonographic evaluation, and the system was extended to include MRI evaluation.