Medical speciality using imaging to diagnose and treat diseases. Imaging techniques include X-rays, ultrasound, computer tomography (CT), nuclear medicine, positron emission tomography (PET), and magnetic resonance imaging (MRI). Interventional radiology is used to apply procedures under the guidance of imaging techniques (angioplasty). Nuclear medical procedures utilise radioactive-labelled drugs administered through different routes. Radiotherapy is widely used for cancer treatment.