Final answer:
False, CT scans or MRI are usually used to examine the brain due to their detailed imaging. Ultrasounds are the preferred and safest imaging technique during pregnancy for monitoring fetal development as they do not use ionizing radiation.
Step-by-step explanation:
An ultrasound is false as the preferred modality for examining the brain. For evaluating the brain, CT scans or MRI are typically used because they provide more detailed images of brain tissue. However, when specifically studying fetal growth and development, ultrasound imaging is the technique of choice due to its safety and non-invasive nature. During pregnancy, ultrasounds are preferred as they are the least invasive of imaging techniques and use no electromagnetic radiation, making them safe for both mother and fetus.
Ultrasound technology works by transmitting high-frequency sound waves into the body to generate an echo signal, which is converted into a real-time image. Despite the image quality being heavily operator-dependent and the inability to penetrate bone and gas, it remains the safest imaging technique particularly for monitoring fetal development during pregnancy. In comparison to other imaging techniques such as CT scans, PET scans, and X-rays, which involve exposure to some level of radiation, ultrasounds provide a much safer alternative.