Technical note: The effect of the 4‐mm‐collimator output factor on gamma knife dose distributions
نویسندگان
چکیده
We present results of investigations of the clinical significance of variations in the value of the 4-mm-collimator output factor, OF(4/18). Changes in treatment volume, dose-volume histograms (DVHs), and isodose distributions were studied, by varying OF(4/18) up to 20%. The variations were performed on a sample of clinical patient treatment plans for which the 4 mm collimator was used. Although smaller effects are noted for the prescription isodose line, greater dosimetric changes occur for higher dose regions within the target.
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