Impact of magnetic field and optimization approach in MR-linac liver stereotactic radiotherapy

Abstract

 Intensity-modulated radiotherapy (IMRT) plans developed for liver masses in various locations should be compared for liver cancer, both with and without a magnetic field. Field and subfield numbers should also be optimized. 62 patients who underwent radiation treatment for liver cancer at Dehli Cancer Hospital were included in this retrospective investigation. A magnetic field-free plan and a static intensity-modulated plan with four alternative optimization strategies were constructed for each patient based on their initial customized intensity-modulated plan. Plans' variations in dosimetric characteristics were contrasted. PTV Dmin rose , Dmax reduced,  D98 increased, and HI decreased when there was no magnetic field in the first quadrant. PTV Dmin rose, Dmax reduced, and HI decreased in the second quadrant without a magnetic field. PTV Dmax dropped, L-P V30 decreased, HI decreased, and PTV Dmin fell in the third quadrant in the absence of a magnetic field. When there is no magnetic field. PTV Dmin dropped,HI reduced, L-P V30 decreased and PTV Dmax decreased. PTV Dmin rose , HI dropped, and D98 increased  in the fourth quadrant without a magnetic field.Each of these distinctions was noteworthy. When creating designs for liver tumors, the dosage effect may be achieved without the use of a magnetic field through the use of a total of 60 subfields in the first area, 80 subfields in the second zone, and 60 or 80 total subfields in the third and fourth zones. A magnetic field has a greater impact on the target dosage in liver cancer patients than it does on doses to organs that are at risk. It is possible to significantly lessen or even completely eliminate the magnetic field's influence by adjusting the maximum total number of subfields in each quadrant.