TI-RADS ACR Thyroid Imaging Reporting and Data System

{
  "applicability": {
    "use_for": "Risk stratification and size-based management of thyroid nodules characterized on ultrasound.",
    "management_exceptions": [
      "previously_biopsied_nodule",
      "PET_avid_nodule",
      "known_thyroid_malignancy"
    ]
  },
  "feature_groups": [
    {
      "id": "composition",
      "selection": "choose_one",
      "options": [
        {
          "id": "cystic_or_almost_completely_cystic",
          "points": 0
        },
        {
          "id": "spongiform",
          "points": 0,
          "stop_scoring_other_groups": true
        },
        {
          "id": "mixed_cystic_and_solid",
          "points": 1
        },
        {
          "id": "solid_or_almost_completely_solid",
          "points": 2
        },
        {
          "id": "cannot_determine_due_to_calcification",
          "points": 2
        }
      ]
    },
    {
      "id": "echogenicity",
      "selection": "choose_one",
      "options": [
        {
          "id": "anechoic",
          "points": 0
        },
        {
          "id": "hyperechoic_or_isoechoic",
          "points": 1
        },
        {
          "id": "hypoechoic",
          "points": 2
        },
        {
          "id": "very_hypoechoic",
          "points": 3
        },
        {
          "id": "cannot_determine",
          "points": 1
        }
      ]
    },
    {
      "id": "shape",
      "selection": "choose_one",
      "options": [
        {
          "id": "wider_than_tall",
          "points": 0
        },
        {
          "id": "taller_than_wide",
          "points": 3
        }
      ]
    },
    {
      "id": "margin",
      "selection": "choose_one",
      "options": [
        {
          "id": "smooth",
          "points": 0
        },
        {
          "id": "ill_defined",
          "points": 0
        },
        {
          "id": "lobulated_or_irregular",
          "points": 2
        },
        {
          "id": "extrathyroidal_extension",
          "points": 3,
          "caveat": "Obvious invasion should be considered malignant until proven otherwise."
        },
        {
          "id": "cannot_determine",
          "points": 0
        }
      ]
    },
    {
      "id": "echogenic_foci",
      "selection": "choose_all_that_apply",
      "options": [
        {
          "id": "none_or_large_comet_tail",
          "points": 0
        },
        {
          "id": "macrocalcifications",
          "points": 1
        },
        {
          "id": "peripheral_rim_calcifications",
          "points": 2
        },
        {
          "id": "punctate_echogenic_foci",
          "points": 3
        }
      ]
    }
  ],
  "score_operation": "Sum composition, echogenicity, shape, margin, and every applicable echogenic-foci point value.",
  "score_map": [
    {
      "points": "0",
      "outcome_code": "TR1"
    },
    {
      "points": "2",
      "outcome_code": "TR2"
    },
    {
      "points": "3",
      "outcome_code": "TR3"
    },
    {
      "points": "4-6",
      "outcome_code": "TR4"
    },
    {
      "points": ">=7",
      "outcome_code": "TR5"
    }
  ],
  "size_thresholds_mm": {
    "TR1": {
      "fna": "never",
      "follow_up": "none"
    },
    "TR2": {
      "fna": "never",
      "follow_up": "none"
    },
    "TR3": {
      "fna_if_gte": 25,
      "follow_if_gte": 15,
      "follow_if_lt_fna": true,
      "follow_up_years": [
        1,
        3,
        5
      ]
    },
    "TR4": {
      "fna_if_gte": 15,
      "follow_if_gte": 10,
      "follow_if_lt_fna": true,
      "follow_up_years": [
        1,
        2,
        3,
        5
      ]
    },
    "TR5": {
      "fna_if_gte": 10,
      "follow_if_gte": 5,
      "follow_if_lt_fna": true,
      "follow_up_years": [
        1,
        2,
        3,
        4,
        5
      ]
    }
  },
  "interval_change": {
    "significant_growth": ">=20% increase in at least two dimensions with an absolute increase of >=2 mm",
    "consequence": "Reapply the management threshold using the new size for the existing TR level."
  },
  "exceptions": [
    {
      "if": "previously biopsied",
      "then": "TR classification may be reported, but management must incorporate pathology; ACR TI-RADS does not provide a standalone recommendation."
    },
    {
      "if": "focal FDG-PET uptake and size >10 mm in a patient with normal life expectancy",
      "then": "ACR FAQ recommends biopsy regardless of TR category; clinical context may alter this in patients with another malignancy."
    }
  ],
  "source_locator": "ACR TI-RADS Atlas and Assessment Categories chart; ACR Diagnostic Ultrasound Reporting Template; ACR TI-RADS FAQ 111-116."
}