Suspicious features include: abnormal lymph nodes and/or invasion of local tissues by
the thyroid nodule. Abnormal lymph node features include: calcifications, cystic
components, and/or increased enhancement.
ACR Spleen Calculator
No follow-up Imaging
Notes:
Benign features include: homogeneous, low density < 20HU, no enhancement, smooth margins
Suspicious features include: heterogeneous, enhancement, irregular margins, necrosis, splenic parenchymal or vascular invasion, substantial enlargement.
ACR Lymph Node Calculator
No follow-up Imaging
Notes:
Benign features include: size < 1cm on short axis, reniform shape, fatty hilum,
normal enhancement, normal cortical thickness
Suspicious features include: size > 1cm on short axis, round shape, indistinct hilum,
necrosis, increased cortical thickness, enlarging
ACR TI-RADS Calculator
3
Mildly Suspicious (TR 3)
FNA if ≥ 2.5 cm Follow if ≥ 1.5 cm
Notes:
If nodule Composition is cystic or almost completely cystic or Spongiform, other categories do not add points and TI-RADS category is benign (TR 1).
ACR Adnexa Calculator
No further imaging
Notes:
Simple cyst features include: oval, circumscribed, homogeneous fluid signals, thin wall,
size < 10 cm
Probably benign features include: not anechoic, angular margin, not round/oval,
partially obscured or indistinct
Suspicious features include: irregular or thick wall/septations, mural nodule, solid
component, hemorrhage in postmenopausal patient
ACR Liver Calculator
Benign, no further follow-up
Notes:
Benign features include: sharp margin, homogeneous low attenuation (20 HU) on
noncontrast and/or portal venous–phase imaging, and characteristic features of
hemangiomas, focal nodular hyperplasia (FNH), focal fatty sparing or deposition, or
perfusional changes.
Suspicious features include: ill-defined margins, heterogeneous density, mural
thickening or nodularity, thick septa, and intermediate to high attenuation on portal
venous–phase imaging (>20 HU, in the absence of pseudo enhancement). If pre- and
postcontrast CT is available, enhancement >20 HU is a suspicious feature.
Low-risk patient: no known primary malignancy, hepatic dysfunction, or hepatic risk
factors.
High-risk patient: known primary malignancy with a propensity to metastasize to the
liver, cirrhosis, and/or other hepatic risk factors
Fleischner Lung Nodule Calculator
No routine follow-up
Notes:
These guidelines do not apply to patients who are younger than 35 years,
immunocompromised, with cancer history, or qualify for lung cancer screening.
High risk factors include: older age, heavy smoking, emphysema, fibrosis, exposure to
asbestos/radiation, first-degree relative with lung cancer, irregular/spiculated
margins or upper lobe location of nodule.
ACR Pancreas Calculator
Reimage q1y x 5, then reimage q2y x 2. Stop if stable over 9 yrs. If interval growth*, consider EUS/FNA
Notes:
Interval growth: if cyst size < 1.5cm, growth defined as 100% increase in
longest-axis diameter for cysts < 0.5cm and 50% increase for cysts between 0.5-1.5cm.
If cyst size >= 1.5cm, growth defined as 20% increase in longest-axis diameter.
ACR Adrenal Calculator
Probably benign, consider follow up adrenal CT in 1 yr
Notes:
Benign features include: macroscopic fat (myelolipoma), calcification, no enhancement,
density < 10HU (adenoma), decreased signals on CE-MRI (adenoma)
ACR Adrenal Washout Calculator
No result %No result %
Notes:
Nodule = lipid-rich adenoma if pre-contrast density < 10 HU
Nodule = lipid-poor adenoma if Absolute washout > 60% and Relative washout > 40%
Otherwise, nodule remains indeterminate and needs additional MRI characterization.
ACR Kidney Calculator
If density is -10 to 20 HU, benign cyst and no further follow-up.
If density >20 HU, complicated or solid cystic mass and follow Bosniak classification
Notes:
Suspicious features include: calcifications, thick or irregular wall/septations, mural
nodule, solid component, enhancing, enlarging
