What is NOT an advantage of onboard imaging (OBI) systems in linear accelerators?

The option indicating "Poor quality images with MV energies" accurately captures a disadvantage rather than an advantage of onboard imaging (OBI) systems. OBI systems are designed to enhance the quality of imaging utilized in conjunction with linear accelerators, primarily by providing high-quality diagnostic images crucial for accurate treatment delivery.

Advancements in technology have enabled OBI systems to produce improved image quality, thus allowing for better visualization of patient anatomy in relation to treatment fields. This improvement also aids in correct beam positioning, thereby increasing the precision of radiation therapy and minimizing exposure to surrounding healthy tissues. Furthermore, these systems contribute to better patient comfort by reducing the need for moving patients between different imaging modalities, making the overall treatment process more streamlined and less stressful for the patient.

In contrast, the mention of poor-quality images under MV energies underscores a limitation rather than any merit of the OBI systems, as high-energy images can sometimes suffer from less clarity compared to lower energy images. This characteristic does not align with the advantages provided by OBI systems, making it the right choice as the option that does not describe an advantage.