Diffusion Time Calculator
Restricted rectangular PGSE effective diffusion timeΔ−δ/3, same timing/no arbitrary mix sequence, max waveforms external. Not pick diffusion clinical scan parameters.
Description
For rectangular pulsed-gradient spin-echo timing, effective diffusion time differs from the leading-edge separation.
For rectangular pulsed-gradient spin-echo timing, effective diffusion time differs from the leading-edge separation.1
This tool subtracts one third of the supplied gradient duration under that restricted timing convention.
When to use Diffusion Time Calculator
This tool subtracts one third of the supplied gradient duration under that restricted timing convention.
How to use Diffusion Time Calculator and how it works
- Prepare pgse gradient leading edge separation seconds, rectangular gradient duration seconds, using the input definitions and matching units below.
- Enter the required fields and run Diffusion Time Calculator.
- Read result.value using the units, signs and ordering explained below.
- Correct any rejected inputs and rerun; interpret the result within the stated model and its assumptions.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| actualPgseGradientLeadingEdgeSeparationSeconds | Actual Pgse Gradient Leading Edge Separation Seconds. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
| actualRectangularGradientDurationSeconds | Actual Rectangular Gradient Duration Seconds. Use the units and matching context stated in the calculation below. | number | Required; strictly positive; finite; other constraints below |
Require positive gradient leading-edge separation Delta and positive rectangular duration delta in seconds, with Delta>=delta. Return Delta-delta/3 as seconds. The restricted rectangular PGSE timing model is not extended to arbitrary waveforms.
effectiveDiffusionSeconds=DeltaSeconds-deltaSeconds/3 Apply the input ordering, units and branch conditions stated above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Object containing the calculated or selected fields below. | object |
| result.value | Restricted effective diffusion time in seconds. | number |
{
"input": {
"actualPgseGradientLeadingEdgeSeparationSeconds": 1,
"actualRectangularGradientDurationSeconds": 0.3
},
"output": {
"result": {
"value": 0.9
}
}
}Limitations and assumptions
The calculation uses the supplied observations and model inputs. It does not collect measurements, select a reference population or coefficient, or establish that the model applies to the actual case. The stated branch conditions and output units remain part of the result.
All fields require explicit values. Unexpected fields, wrong types, nonfinite numbers and sparse arrays are rejected. Alignment, bounds and supported-token rules are explained above; extremely large inputs or nonfinite results can also fail. Input errors differ from successful false comparisons, unavailable-domain flags and empty match lists.
Alternative or Complementary methods
Use Radial Diffusivity MRI Calculator for a complementary operation: Radial diffusivity averages the two smaller eigenvalues of an independently fitted diffusion tensor.
Use Voxel Volume Calculator for a complementary operation: Rectangular voxel volume combines readout size, phase size and actual slice thickness.
References
-
Diffusion Time Calculator — tool.io
Similar or alternative tools
- Radial Diffusivity MRI Calculator
Radial diffusivity averages the two smaller eigenvalues of an independently fitted diffusion tensor.
- Voxel Volume Calculator
Rectangular voxel volume combines readout size, phase size and actual slice thickness.