What is the purpose of lead plates in X-ray therapy?

Lead plates are utilized in X-ray therapy primarily to protect healthy tissues from unnecessary exposure to radiation. This is crucial because while X-rays can target cancerous cells effectively, surrounding healthy tissue is also at risk when radiation is applied. The lead plates act as a barrier, absorbing some of the X-ray radiation and ensuring that the high levels of radiation needed to treat tumors do not adversely affect nearby healthy cells. By doing so, the treatment can be more targeted, minimizing collateral damage and potential side effects for the patient.

The other options, although relevant to different contexts of X-ray use, do not directly pertain to the primary function of lead plates in therapy. For instance, enhancing image contrast is more related to imaging techniques rather than therapeutic procedures, cooling the X-ray machine pertains to maintaining operational efficiency, and improving patient comfort is a secondary concern unrelated to the protective role of lead.