Spine SRS

Tartalomjegyzék

Plan Analysis Table

Plan Analysis Table Menu



No.

Component

Slider settings for the PTV:

Weighting: Sets the importance of the PTV versus the OARs for the calculation.

Weighting on the PTV (leftmost position):

  • Disables any strict constraint for the most important OAR

  • Guarantees the PTV volume prescription will be fulfilled (unless Dose Shaper is used, see below)

Weighting towards the PTV results in:

  • Higher PTV volume coverage

  • Higher PTV dose homogeneity

  • Improved fulfillment of the upper dose constraint

Weighting towards the OAR results in:

  • Improved fulfillment of OAR constraints

  • Improved normal tissue sparing

  • More relaxed PTV volume prescription

Normal Tissue Sparing: Controls the importance of sparing all normal tissue surrounding the PTV.

High normal tissue sparing results in:

  • A steeper dose gradient

  • Lower (better) CI and GI values

Modulation: Controls the amount of modulation by setting the VMAT dose modulation components.

High modulation results in:

  • Higher number of monitor units

  • More leaf motion between control points

  • More leaf movement within one segment

  • Smaller field sizes

  • Variation between the monitor units of control points of all arcs

Setting Modulation to Low (the lowest setting available) will not produce a dynamic conformal arc. Instead, this setting causes deactivation of the dose modulation (e.g., no change in dose rate and gantry speed) between control points. The resulting treatment plans are similar to dynamic conformal arc plans from iPlan RT Dose with manually adjusted leaf positions. This might lead to treatment plans with less demanding quality assurance requirements.

Settings for the PTV, PTV – boost and boost:

  • Prescription: Number of fractions and prescribed dose

  • Prescription volume: Desired percentage of the PTV that should be covered by the prescription dose
  • D%/DMAX: Maximum/desired dose constraint on the PTV

Slider settings for the most important OAR:

Dose volume constraints: The maximum volume of the most important OAR that is allowed to receive the dose indicated for which the importance can be changed by adjusting the sliders.

  • Off: The OAR constraint will not be taken into account during the optimization.

  • Smart: The optimizer will penalize any violation of the OAR constraint. However, the optimizer will still take other constraints into consideration.

  • Strict: The OAR constraint is given very high importance.

Slider settings for all other OARs:

  • Guardian: Sets the importance of the selected OAR relative to the other OARs and the PTV.

  • Dose volume constraints: The maximum volume of an OAR that is allowed to receive the dose indicated for which the importance can be changed by adjusting the sliders.

Select Configuration to open the list of available Protocol and Setup options and to enable the Advanced Editing mode (see below).

The colored circular symbols indicate the most severe violation of the respective constraints. For example, if the coverage dose is met (green) but the dose for the desired constraint exceeds the tolerance (red), the symbol is red.

Other circular symbols for objects:

  • Solid gray circle: The dose is not available for the object or no constraint is defined for the object

The colored dose/volume values in the Plan Analysis table are defined as follows:

  • For PTV/PTV-Boost/Boost:

    • Coverage dose:
      • Green: The coverage dose is met
      • Yellow: The coverage dose is not met for the coverage volume, but is met for the tolerated coverage volume
      • Red: The coverage dose is not met for the tolerated coverage volume
    • Maximum dose constraint (non-SRS prescription mode only):
      • Green: The dose is below the constraint
      • Yellow: The dose exceeds the constraint, but is within the tolerance
      • Red: The dose exceeds the constraint and is above the tolerance
    • Desired dose constraint (SRS prescription mode only):
      • Green: The dose is within the tolerance
      • Red: The dose exceeds the tolerance in either direction (below or above)
  • For OARs:

    • Green: The dose is ≤ the constraint
    • Yellow: The dose exceeds the constraint, but remains within the tolerance
    • Red: The dose exceeds the tolerance range of the constraint
Art-No. 60919-40EN

A kibocsájtás napja: 2019-05-22