Evaluation and Optimization of Absorbed Dose to the Eye Lens in Various Intensity-Modulated Radiation Therapy (IMRT) Techniques for Treatment of Frontal Area Tumors

Background: In this study, a comparison was performed between various intensity-modulated radiation therapy (IMRT) techniques for treatment of frontal area tumors in order to achieve the optimal treatment technique considering absorbed dose to the eye lens. Methods: Treatment planning and contouring were performed with TiGRT software for 20 patients with frontal area tumors. Three techniques were compared to each other. Finally, by comparing the dose volume histograms, the average dose received by each organ was determined and the best method was selected. Findings: In all three techniques, isodose curve of 30% passed through the eye, but the important point was that the curves were shifted towards the bottom of the eye with increasing the number of fields. Conclusion: The dose in the second technique was less than the other techniques. In this technique, there are five fields, and the path of the field does not go through the eye directly.