Isodose Window

The Isodose window provides controls that determine how isodose lines and surfaces are displayed. You can create isodose legend preset (.idos6) files in the Custom Isodoses dialog, and then access those files from the Legends menu. Note: each plaque has its own legend settings.

To quickly edit only an isodose color simply click the associated color well control. Double-clicking on any of the displayed legend values or clicking the Customize... button opens the Custom Isodoses dialog.


The Isodose window as it might appear when plotting absolute dose. The legend file 'MyFavorite' has been opened from the Select menu (or set as the startup preference).


The Isodose window as it might appear when plotting isodose lines that have been normalized to the dose delivered to a selected point such as the prescription point which in this example was the tumor apex. The Normalize to button is checked, a normalization value and point have been selected, and the legend file 'Normalized' has been opened from the Select menu.


Drag the window's right edge to widen the window and reveal the Standard vs Alternate legend selector in the toolbar. The standard legend is used to plot isodose lines and surfaces for the standard dosimetry set which consists of the retinal diagram, the meridian and coronal 2D dosimetry planes, and 3D dosimetry.


The alternate legend is applied to surfaces that are not members of the standard dosimetry set. The optic nerve 2D dosimetry plane is such an alternate surface. In this example a variation of the "MyFavorite" file has been loaded which plots a different set of isodose lines which focus on the 5 to 30 Gy range (vs the 60 to 400 Gy range featured in the original file). You can set a startup preference for both the standard and alternate legends.

Upper controls group

The Normalize checkbox normalizes isodose displays to the displayed value (e.g. 1.0 by default) at the point selected in the popup menu. The default normalization point is the prescription (Rx) point.


When the plaque is empty, the dose at the prescription (Rx) point is zero, so the normalization menu substitutes Rx Dose (e.g. 85 Gy) for Rx Point.


The normalization point can be changed to various locations (e.g. the tumor apex) from the Normalize at pop-up menu.


Plaque 1..4 - Selects the plaque (and its associated dose matrices) that is currently "active". Each plaque has its own legend settings.


The Legends pull-down menu lists the isodose legend (.idos6) files that are in Plaque Simulator's master data folder and the most recently selected file. Use this menu to select a legend file. You may also drag & drop an isodose legend file (.idos6) or colors file (.iclr6) on the legend in this window (v6.8.2). Note: if the legend settings have changed significantly since a legend file was opened, the Legends control will display Select rather than the file name.

Center controls group

The column of checkboxes (titled 2D) to the left of the legend selects which isodose lines are plotted on 2D dosimetry surfaces such as the meridian and coronal planes and the retinal diagram.

The column of radio buttons (titled 3D) selects the isodose surface which is rendered in the Setup window. The 3D radio button column will allow only a single selection when in Single 3D mode.


In Multiple 3D mode, the 3D isodose surfaces button column allows multiple selections.


To change an isodose color click on the color well control to the right of the radio buttons. This will open the MacOSX Color picker.

Footer controls

The Single 3D button toggles between Single 3D and Multiple 3D modes.

The Customize... button opens the Custom Isodoses dialog.


The Isodose Units pop-up menu selects Plaque Simulator's isodose plotting units. This control is duplicated in the footer controls of the Planar Dosimetry and Retinal Diagram windows.