Echocardiography is the ultrasound examination of the heart. Depending on the used ultrasound system, echocardiograms can be two-dimensional slices or 3D real-time images of the heart. Based on the ultrasound principles the direction and speed of blood flow can be utilized e.g., to diagnose a leaking or stenosed valve or to identify intracardiac shunts.

Different types of echocardiography:
The transthoracic echocardiogram (images are taken through the chest wall) is a non-invasive, highly accurate and quick assessment of the overall health of the heart.
A more invasive method is to insert a specialized scope containing an echocardiography transducer (TEE probe) into the esophagus, and record images from there. The advantages are clearer images, since the transducer is closer to the heart.
Contrast echocardiogram (CE) is already a valuable tool to delineate endocardial borders, direct invasive procedures, detect intracardiac shunts, assess myocardial perfusion and viability, and quantify coronary flow reserve and blood volumes (see also hemoglobin). The mechanism of microbubble CE is based on the physical principles of rarefaction and compression, leading to volume pulsations of microbubbles, and it is this change that results in CE signal.
Stress echocardiograms are echocardiography exams used for detection of coronary artery disease.

See also Diastole, Bicycle Stress Echocardiography, Resistive Index, and M-Mode Echocardiography.

(MIP) Angiography (Doppler) images can be processed by Maximum Intensity Projection to interactively create different projections. Although the maximum intensity projection (MIP) post processing algorithm is sensitive to high signal from inflowing spins as used in MRI, it is also sensitive to high signal of any other etiology as used in ultrasound imaging. The MIP connects the high intensity dots of the blood vessels in three dimensions, providing an angiogram that can be viewed from any projection. Each point in the MIP represents the highest intensity experienced in that location on any partition within the imaging volume.
For complete interpretation the base slices should also be reviewed individually and with multiplanar reconstruction (MPR) software. The MIP can then be displayed in a CINE format or filmed as multiple images acquired from different projections.

See also 3D Ultrasound.

The definition of imaging is the visual representation of an object. Medical imaging is a broad term that encompasses various imaging modalities and techniques used in the field of medicine to visualize and study the body's anatomy and physiology. It includes both diagnostic and non-diagnostic imaging procedures, where diagnostic imaging specifically refers to the subset of medical imaging techniques that are primarily focused on diagnosing diseases or conditions. Medical imaging techniques are employed to obtain images or visual representations of the internal organs, tissues, and structures, aiding in the diagnosis, treatment, and monitoring of medical conditions.
The field of medical imaging has significantly evolved since the discovery of X-rays by Konrad Roentgen in 1896. Initially, radiological imaging involved focusing X-rays on the body and capturing the images on a single piece of film within a specialized cassette. Subsequent advancements introduced the use of fluorescent screens and special glasses for real-time visualization of X-ray images.
A significant breakthrough came with the application of contrast agents, enhancing image contrast and improving organ visualization. In the 1950s, nuclear medicine studies utilizing gamma cameras demonstrated the uptake of low-level radioactive chemicals in organs, enabling the observation of biological processes in vivo. Currently, positron emission tomography (PET) and single photon emission computed tomography (SPECT) technologies play pivotal roles in clinical research and the diagnosis of biochemical and physiological processes. Additionally, the advent of the x-ray image intensifier in 1955 facilitated the capture and display of x-ray movies.
In the 1960s, diagnostic imaging incorporated the principles of sonar, using ultrasonic waves generated by a quartz crystal. These waves, reflecting at the interfaces between different tissues, were received by ultrasound machines and translated into images through computer algorithms and reconstruction software. Ultrasound (ultrasonography) has become an indispensable diagnostic tool across various medical specialties, with immense potential for further advancements such as targeted contrast imaging, real-time 3D or 4D ultrasound, and molecular imaging. The first use of ultrasound contrast agents (USCA) dates back to 1968.
Digital imaging techniques were introduced in the 1970s, revolutionizing conventional fluoroscopic image intensifiers. Godfrey Hounsfield's pioneering work led to the development of the first computed tomography (CT) scanner. Digital images are now electronic snapshots represented as grids of dots or pixels. X-ray CT brought about a breakthrough in medical imaging by providing cross-sectional images of the human body with high contrast between different types of soft tissue. These advancements were made possible by analog-to-digital converters and computers. The introduction of multislice spiral CT technology dramatically expanded the clinical applications of CT scans.
The first magnetic resonance imaging (MRI) devices were tested on clinical patients in 1980. With technological improvements, such as higher field strength, more open MRI magnets, faster gradient systems, and novel data-acquisition techniques, MRI has emerged as a real-time interactive imaging modality capable of providing detailed structural and functional information of the body.
Today, imaging in medicine offers a wide range of modalities, including:

These imaging modalities have become integral components of modern healthcare. With the rapid advancement of digital imaging, efficient management has become important, leading to the expansion of radiology information systems (RIS) and the adoption of Picture Archiving and Communication Systems (PACS) for digital image archiving. In telemedicine, real-time transmission of all medical image modalities from MRI to X-ray, CT and ultrasound has become the standard. The field of medical imaging continues to evolve, promising further innovations and advancements in the future, ultimately contributing to improved patient care and diagnostics.

See also History of Ultrasound Contrast Agents, and History of Ultrasound.

In 1918, Philips started with their first medical X-ray tube. Philips Medical Systems now is a global leader in diagnostic imaging systems, healthcare information technology solutions, and patient monitoring and cardiac devices. Philips also provides customer services such as financing, consultancy and maintenance & repair.
Philips lacked in the field of ultrasound till 1998. By buying ATL (Bothell, Washington) in this year Philips establishing itself as an important player in ultrasound. In 2001 Philips also acquired Agilent (formerly Hewlett-Packard; Andover, Massachusetts), a market leader in the cardiology and vascular ultrasound systems (HP2000 to HP5500, now Sonos 2000 to Sonos 5500).

Philips Medical System is the diagnostics business of Royal Philips Electronics of the Netherlands, one of the world's biggest electronics companies and Europe's largest. Philips is quoted on the NYSE (symbol: PHG), London, Frankfurt, Amsterdam and other stock exchanges. On October 19, 2001, Philips Medical Systems completed a 3-year acquisition strategy through its purchase of Marconi Medical Systems. Marconi Medical Systems offered leading multislice CT, MRI, and Nuclear Gamma Camera systems to medical institutions around the world. As well as new 3.0T developments, Philips is also in collaboration with researchers at the University of Nottingham, with the intention of developing an ultrahigh field strength clinical 7.0T whole body MR system.

Ultrasound Systems:

A plane, slice or section of the body cutting from front to back through the sagittal suture of the skull, and continued down through the body in the same direction, dividing it into two parts.