A computationally efficient and accurate procedure for calculating
radiation dose distributions within a volume of interest in a patient
incorporating variations in patient density and source particle energy,
position, direction, and type. The procedure iteratively simulates energy
depositions from source particles using the Monte Carlo radiation
transport method and then applies methods for reducing noise inherent in
Monte Carlo results to obtain an accurate and computationally efficient
representation of an actual radiation dose distribution compared to that
produced by Monte Carlo methods alone. The invention makes an analogy
between real measured data and transformed Monte Carlo generated computer
data and then applies data denoising techniques to reduce the noise in the
Monte Carlo dose images. Conversely, the present invention can produce a
dose distribution having a predetermined noise level in a reduced amount
of computation time. Denoising techniques can include digital filtering,
wavelet denoising, kernel smoothing and non-parametric regression
smoothing.
