Optic Nerve Sheath Diameter Calculator
Actual protocol-matched left/right optic-nerve-sheath repeat measurements, not infer intracranial pressure from an arbitrary universal cutoff. Measurement depth, plane, device and qualified assessment external.
Description
Optic-nerve sheath diameter summarizes independently measured left and right samples.
Optic-nerve sheath diameter summarizes independently measured left and right samples.1
Bilateral means and their discrepancy do not estimate intracranial pressure.
When to use Optic Nerve Sheath Diameter Calculator
Use this tool to calculate or review the supplied observations under the stated rules. Establish the assessment or recording protocol, units, instrument version and independently applicable reference or calibration.
How to use Optic Nerve Sheath Diameter Calculator and understand its results
- Establish the assessment or recording protocol, units, instrument version and independently applicable reference or calibration.
- Enter independentlyMeasuredLeftOnsDiametersMm, independentlyMeasuredRightOnsDiametersMm, using the field meanings and rules below, then run the tool.
- Read result.observedLeftMeanOnsDiameterMm, result.observedRightMeanOnsDiameterMm, result.signedRightMinusLeftMeanMm. Use the units and sign conventions below.
- Correct any reported input issue and run again. Before using a successful result, check the stated units, signs, reference scope and observation coverage.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| independentlyMeasuredLeftOnsDiametersMm | Independently measured left ons diameters mm | list of number | Required |
| independentlyMeasuredRightOnsDiametersMm | Independently measured right ons diameters mm | list of number | Required |
Require nonempty strictly positive left and right diameter sample lists. Compute each arithmetic mean separately and right-minus-left mean. The list lengths need not match.
leftMean=mean(leftSamples); rightMean=mean(rightSamples); signedDifference=rightMean−leftMean Use the matching field units and the exact boundary, ordering and reference rules above.
| Output field | Meaning | Value type |
|---|---|---|
| result | Structured result; its nested fields below contain the actual calculation or selected reference | object |
| result.observedLeftMeanOnsDiameterMm | Observed Left Mean Ons Diameter Mm | number |
| result.observedRightMeanOnsDiameterMm | Observed Right Mean Ons Diameter Mm | number |
| result.signedRightMinusLeftMeanMm | Signed Right Minus Left Mean Mm; preserve the subtraction order and sign defined in the mechanics | number |
{
"input": {
"independentlyMeasuredLeftOnsDiametersMm": [
4,
6
],
"independentlyMeasuredRightOnsDiametersMm": [
5,
7
]
},
"output": {
"result": {
"observedLeftMeanOnsDiameterMm": 5,
"observedRightMeanOnsDiameterMm": 6,
"signedRightMinusLeftMeanMm": 1
}
}
}Limitations and assumptions
Actual acquisition, assessment protocol, instrument version and calibration determine applicability. The tool does not examine a person, classify images, administer a questionnaire or choose diagnostic cutoffs.
Missing required fields, unknown fields, wrong types and violated rules return input issues. Numeric values and outputs must be finite. Lists and matrices must be dense, without missing cells. Numeric lists allow at most 10000 entries; ordinary string lists allow at most 128 strings of 128 UTF-16 units each; numeric matrices allow at most 128 rows and 128 columns, subject to narrower requirements above. Extremely large composite outputs are rejected.
Alternative or Complementary methods
For a related step, use Corrected Intraocular Pressure Calculator: Intraocular-pressure correction depends on the actual measurement method and applicable reference. For a complementary comparison, use Speech Reception Threshold Calculator: Speech reception threshold depends on a specified test procedure and measurement convention.
References
-
Optic Nerve Sheath Diameter Calculator — tool.io
Similar or alternative tools
- Corrected Intraocular Pressure Calculator
Intraocular-pressure correction depends on the actual measurement method and applicable reference.
- Speech Reception Threshold Calculator
Speech reception threshold depends on a specified test procedure and measurement convention.