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The Dose Area (or volume) Histogram can be a 1 to 4 page document.
- Plot #1 - By default, a cumulative dose-area histogram of the retinal surface. Use the Retina-Dose-Area Histogram (RDAH) to confirm dosimetric coverage (e.g. 85 Gy) of the tumor base (GTV) and tumor base + margin (PTV), and to find seed loading patterns that reduce dose to critical regions such as the macula and optic disc. A Dose-Volume Histogram (DVH) can also be calculated, but it is not as useful because the critical regions of the eye can have irregular base shapes located in the thin retinal and choroidal layers which are better modeled by a surface area calculation. The most useful DVHs are the volumes of the lens and the cornea. The cornea is modeled by voxels comprising a spherical bowl with default shell thickness of 0.55 mm (cornea thickness, height and curvature are user customizable via the Setup window's size control). Dose to voxels located in the fluid filling the anterior chamber is ignored when calculating the cornea DVH. The DVH voxel resolution is user customizable via the P# Histogram #2 Options menu. Medium resolution results in a cornea calulation using about 550 voxels. High resolution uses about 4700 voxels to model the cornea.
- Plot #2 - By default a differential RDAH.