Figure 2From: Independent absorbed-dose calculation using the Monte Carlo algorithm in volumetric modulated arc therapyComputed tomographic image of a cork phantom (RT-3000-New-Water with cork, R-Tech, Japan) mapping a dose distribution. The low-density area is composed of the piled components of the cork. A spherical insert of 3 cm in diameter is placed anywhere inside the cork, and a 0.015-mL pinpoint ionization chamber can be inserted.Back to article page