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Published online: 2024-06-13

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Unravelling the landscape of image-guided radiotherapy: a comprehensive overview

Gautam Sarma1, Hrishikesh Kashyap1, Partha Pratim Medhi1, Rupam Kalita1, Dhanjit Lahkar1


Image-guided radiation therapy (IGRT) is essential to modern radiation therapy. It ensures precise radiation delivery to tumor targets, sparing healthy cells and tissues. IGRT techniques upgraded themselves to a level where the technology allows for tracking the real-time image of the tumor during treatment and significantly improves the accuracy and precision of radiation therapy. By integrating advanced imaging modalities such as cone beam computed tomography, magnetic resonance imaging, and positron emission tomography, clinicians can visualize the tumor and surrounding tissues in three dimensions. It also can account for intrafraction variations, such as organ motion and changes in tumor size or shape, which can occur throughout treatment. Using IGRT techniques, clinicians can adapt the treatment plan in real-time to ensure optimal radiation delivery to the tumor while sparing healthy tissues. Moreover, IGRT is crucial in managing systematic and random errors during radiation therapy. These errors could lead to underdosing of the tumor or overdosing of healthy tissues, compromising treatment efficacy and patient safety. To mitigate these errors, imaging and frequent verification of the treatment are necessary throughout the treatment. This review paper offers a comprehensive summary of IGRT, its diverse modalities, clinical integration, quality assurance tests performed, and the role of artificial intelligence (AI) in IGRT.

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