Radikulus

Free radiology calculators for the reading room

Enter a few measurements and see where they fall against published criteria. Every page stays dark, so your eyes stay adjusted.

Browse calculatorsOpen WashWizard

Results

Absolute washout APWAbsolute percentage washout: 100 × (Enhanced − Delayed) / (Enhanced − Unenhanced). Decides the category when an unenhanced value is available; adenoma range ≥60% (ACR 2017).
56.7%
Relative washout RPWRelative percentage washout: 100 × (Enhanced − Delayed) / Enhanced. Decides the category only when no unenhanced value is available; adenoma range ≥40% (ACR 2017).
37.3%

Washout category

Decision order, top to bottom
StepCriterionMeaningThis lesion
W1Step 1 of this calculator’s decision order, applied top to bottom. A Radikulus step label, not an ACR category.Unenhanced ≤10 HUUnenhanced attenuation at or below 10 HU, checked first.Low unenhanced attenuationUnenhanced attenuation ≤10 HU is consistent with benign low-density features. For a homogeneous lesion, ESE recommends no further adrenal imaging; possible entities include lipid-rich adenoma, myelolipoma and a fluid-filled cyst.
W2Step 2 of this calculator’s decision order, applied top to bottom. A Radikulus step label, not an ACR category.Early and delayed enhancement <10 HULess than 10 HU change from unenhanced on the early phase, without delayed enhancement ≥10 HU.Washout not applicableNo measurable early enhancement (<10 HU change); washout is not applicable. ACR considers a mass without enhancement a cyst or hemorrhage requiring no follow-up imaging.
W3Step 3 of this calculator’s decision order, applied top to bottom. A Radikulus step label, not an ACR category.Delayed > enhancedDelayed attenuation exceeds enhanced attenuation.No washout: indeterminateNo washout: not adenoma-typical — indeterminate.
W4Step 4 of this calculator’s decision order, applied top to bottom. A Radikulus step label, not an ACR category.APW ≥60%Absolute percentage washout: 100 × (Enhanced − Delayed) / (Enhanced − Unenhanced). Decides the category when an unenhanced value is available; adenoma range ≥60% (ACR 2017).Adenoma rangeWashout at or above the adenoma threshold. ESE 2023 (PMID 37318239): evidence for accuracy of these cutoffs in adrenal incidentalomas was very low.
W5Step 5 of this calculator’s decision order, applied top to bottom. A Radikulus step label, not an ACR category.APW <60%Absolute percentage washout: 100 × (Enhanced − Delayed) / (Enhanced − Unenhanced). Decides the category when an unenhanced value is available; adenoma range ≥60% (ACR 2017).IndeterminateIndeterminate by washout criteria (absolute washout <60%).APWAbsolute percentage washout: 100 × (Enhanced − Delayed) / (Enhanced − Unenhanced). Decides the category when an unenhanced value is available; adenoma range ≥60% (ACR 2017).56.7%
WashWizard on a published case: Kwek KJH, Yeo CP, Ho BCS, Kon YC 2024, PMID 38487512 (unenhanced 35, enhanced 102, delayed 64 HU, 2 cm).

Calculators

Body CT

Chest CT

Organ volumes

Musculoskeletal

How the calculators are built

Criteria you can see
Each calculator names the guideline it follows, links to the source and says when it was last checked for newer criteria.
Imaging findings only
Results characterize the finding and give imaging next steps. Clinical guidance stays in the article, with a link to the guideline.
Simulate uses real cases
Simulate loads published cases, cited by PMID, or cases clearly labelled hypothetical. Cases are never made up.
Checked twice
Thresholds and wording are fact-checked against primary sources, and results are tested against an independent reference implementation.

WashWizard is the first calculator built to this standard; the others are being moved to it.