Functional diagnostics and imaging

Functional diagnostics and imaging

Functional diagnostics and imaging techniques are two central pillars within medical diagnostics. They provide different but often complementary information about the condition of organs, tissues, and body functions, allowing the doctor to obtain a comprehensive picture of the patient's condition. For example, in the case of suspected coronary artery disease, a functional stress test is combined with imaging of the coronary arteries. Both methods together enable more precise diagnosis, better monitoring, and individually tailored therapy decisions. Functional diagnostics involve examinations that assess the performance and functioning of organs or physiological systems. Unlike purely structural imaging, it is not only concerned with whether an organ is anatomically intact but also whether it is functioning correctly. A classic example is the ECG (electrocardiogram), which records the activity of the heart. Other typical procedures include pulmonary function testing, which measures lung volume and airflow speed, or ergometry, which tests the cardiovascular system under stress. Long-term measurements such as the 24-hour blood pressure profile or long-term ECG also belong to functional diagnostics. In contrast, imaging diagnostics use technical procedures to produce visual representations of structures inside the body. The goal is to make anatomy, changes, lesions, or pathological processes visible. Important imaging procedures include X-ray diagnostics, sonography (ultrasound), computed tomography (CT), magnetic resonance tomography (MRT), and nuclear medicine (e.g., PET or scintigraphy). While X-rays and CT are particularly suitable for bones and lungs, MRT provides detailed images of soft tissues such as the brain, spinal cord, muscles, or joints. Sonography is often used to examine abdominal organs, vessels, or the heart (as echocardiography). Nuclear medicine procedures even make it possible to visualize metabolic processes, such as the metabolism of glucose in tumor tissue.