What this calculator does
Structures multiparametric breast MRI descriptors into a Kaiser Score from 1 to 11.
Confirm lesion enhancement, then follow the root sign, kinetic curve, margin or internal-enhancement, and edema branches.
Before you calculate
- Confirm a technically adequate contrast-enhanced multiparametric breast MRI and that the target lesion enhances.
- Identify lesion type, root sign, kinetic curve, margin or internal enhancement, and ipsilateral edema before following the tree.
Clinical scope
Use the Kaiser Score to structure assessment of a contrast-enhancing breast lesion on technically adequate multiparametric MRI. The score combines morphology and enhancement kinetics into an ordinal malignancy-risk phenotype.
Applicability and exclusions
- Do not assign a Kaiser Score when the lesion does not enhance; non-enhancement still requires correlation with the indication and complete examination.
- Do not use the score as a substitute for technical quality assessment, BI-RADS reporting, pathology, or multidisciplinary clinical management.
- This basic implementation does not apply optional mammographic microcalcification or ADC moderators.
Method and calculation logic
After confirming enhancement and lesion type, follow the decision tree through spiculation/root sign and kinetic curve. Depending on that branch, margin, internal enhancement pattern, or ipsilateral edema determines the final score from 1 to 11.
Interpretation table
| Score | General interpretation |
|---|---|
| 1-4 | Minimal malignancy risk; BI-RADS 2/3 phenotype |
| 5-7 | Intermediate malignancy risk; BI-RADS 4 phenotype |
| 8-11 | High malignancy risk; BI-RADS 5 phenotype |
Common failure modes
- Scoring a nonenhancing lesion or using descriptors from a technically inadequate examination.
- Using the score as a substitute for the complete BI-RADS assessment, pathology, or clinical management.
The Kaiser Score is a structured MRI phenotype; the final assessment still requires the complete examination and BI-RADS context.
Worked example
Case: Fictional example: an enhancing mass has a root sign, a wash-out curve, and ipsilateral edema.
Calculation: Enhancement present -> mass -> root sign present -> wash-out -> edema present.
Interpretation: The decision-tree endpoint is Kaiser Score 11, a highly suspicious BI-RADS 5 phenotype.
How to use this calculator
- Complete the visible imaging and measurement fields. Required inputs are marked in the workbench.
- Review the calculated category, score, measurements, and any recommendation or warning.
- Copy the report-ready text only after checking the result against the complete examination and source guideline.
Calculator-specific questions
Does lesion type change the numerical score?
The same decision endpoints apply to mass and non-mass enhancement, but lesion type remains important for accurate description and interpretation.
What threshold is considered suspicious?
Scores of 5 or higher are suspicious in the published decision rule; the final BI-RADS assessment and management must use the complete examination and clinical context.
Are patient measurements sent to RadPhrases?
No. Calculator inputs and results are processed in the browser and are not submitted by this page.