Description
Ideal elliptical projected-area ratio from supplied research diameters; no lesion segmentation or treatment-response classification.
Research lesion records distinguish measured dimensions, geometric size models, censoring conventions, assessment denominators, and follow-up timing. An axis product, percent change, or coverage measure describes only its stated inputs and model. Such arithmetic does not automatically implement a clinical response criterion or validate a study.
Ideal elliptical projected-area ratio from supplied research diameters; no lesion segmentation or treatment-response classification.
When to use this tool
Use Tumor Research Ellipse Area Change Term when you need this research measurement, assessment-base, source, or event-time calculation.
How to use the tool and how it works
- Enter firstLong, firstShort, secondLong, secondShort. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read firstArea, secondArea, areaRatio. Use the output convention below.
For positive firstLong and firstShort and nonnegative secondLong and secondShort return firstArea=pi*firstLong*firstShort/4, secondArea similarly, and areaRatio=secondLong*secondShort/(firstLong*firstShort).1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| firstLong | Positive full ellipse diameter, not a semiaxis. | Required. Finite number; strictly above 0. |
| firstShort | Positive full ellipse diameter on the same length basis. | Required. Finite number; strictly above 0. |
| secondLong | Second Long | Required. Finite number; minimum 0. |
| secondShort | Second Short | Required. Finite number; minimum 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| firstArea | First Area | Required. Finite number. |
| secondArea | Second Area | Required. Finite number. |
| areaRatio | Area Ratio | Required. Finite number. |
{
"input": {
"firstLong": 20,
"firstShort": 10,
"secondLong": 10,
"secondShort": 10
},
"output": {
"firstArea": 157.07963267948966,
"secondArea": 78.53981633974483,
"areaRatio": 0.5
}
}Limitations and assumptions
- Inputs are full ellipse diameters in one length unit, not semiaxes. The area model does not establish lesion identity, image orientation, measurement accuracy, formal response categories, or clinical meaning.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use the intended study protocol and a complete measurement or analysis model for a broader conclusion. Verify lesion definitions, censoring, measurement correspondence, time anchors, and missing-assessment policy.
References
Similar or alternative tools
- Tumor Volume Research Axis Product Term
Three-axis model-volume comparison with an explicit common shape coefficient, without image segmentation or response criteria.
- Tumor Research Diameter Percent Change
Descriptive research diameter change and instrument-resolution units, without response criteria, staging or a clinical decision.