Mammography is a diagnostic imaging procedure of the breast to detect and evaluate breast disease. Mammography is widely used as a screening method and plays a key role in early breast cancer detection.
The screening mammography is used to detect breast changes in women who have no signs or symptoms or noticed breast abnormalities. The goal is to detect a breast tumor before any clinical signs are observable.
A diagnostic mammography is used to investigate suspicious breast changes, such as a breast lump, an unusual skin appearance, breast pain, nipple thickening or nipple discharge.
A breast screening or standard mammography requires two mammograms from different angles of each breast including craniocaudal view and mediolateral view. Additional images can be made from other angles or focus on microcalcifications or other suspicious areas.
A mammogram is created by special mammography equipment with long wavelength of the used x-rays. Film-screen mammography is still the most widely used technology, but the state of the art technique is digital mammography. Conventional x-ray equipment was used to produce mammograms until dedicated mammography equipment became available in the late 1960s. Film-screen mammography and xeromammography, introduced in the early 1970s, used lower radiation doses and produced sharper mammograms. The second generation of mammography systems has been introduced in the early 1980s. Chief disadvantages of analog mammography include the labor-intensive handling of the cassettes, relatively slow processing time, the lack of a direct interface to the x-ray system, and no post processing possibilities.
Mammograms of high quality should be done with the lowest radiation dose as possible. Adequate breast compression is important due to shortening of the exposure times, immobilization of the breast, reduction of motion and blurring and prevention of overpenetration by means of equalizing breast thickness.
Further breast imaging procedures include breast ultrasound and breast MRI.

(MPI) The myocardial perfusion scan is the most common nuclear medicine procedure in cardiac imaging and allows assessing the blood-flow patterns to the heart muscles. The comparison of the radiopharmaceutical distribution after stress and at rest provides information on myocardial viability and cardiac perfusion abnormalities. ECG-gated myocardial perfusion imaging allows the assessment of global and regional myocardial function such as wall motion abnormalities.
The diagnostic accuracy of myocardial perfusion scintigraphy (also abbreviated MPS) allows reliable risk stratification and guides the selection of patients for further interventions, such as revascularization. MPI also has particular advantages over alternative techniques in the management of a number of patient subgroups, including women, the elderly, and those with diabetes. The use of this type of cardiac scintigraphy is associated with greater cost effectiveness of treatment, in terms of life-years saved, particularly in these special patient groups.
Myocardial perfusion scintigrams are acquired with a gamma camera. Single photon emission computed tomography (SPECT) is preferred over planar imaging because of the three dimensional nature of the images and their superior contrast resolution.
Common MPI radiopharmaceuticals, approved by the U.S. Food and Drug Administration (FDA) include: Tl-201 and the Tc-99m-labeled radiopharmaceuticals, such as sestamibi, tetrofosmin, and teboroxime for single-photon imaging. Rb-82 is used for positron emission tomography (PET) imaging.

See also Gated Blood Pool Scintigraphy, Myocardial Late Enhancement, Cardiac MRI and Echocardiography.

See Myocardial Perfusion Imaging.
Myocardial scintigraphy is a nuclear cardiology method for the diagnosis of various forms of heart disease.

See also Myocardial Late Enhancement, Cardiac MRI and Echocardiography.

Radiography is a synonym for the examination of the structure of materials by nondestructive methods, for example with radiation. Radiography is used for both medical and industrial applications.
Autoradiography describes the imaging of an object using radiations produced by the radioactive decay of nuclides in the object.
Sometimes, imaging modalities without use of radiation such as MRI and ultrasound are grouped in radiography due to the fact that the radiology staff handles different forms of medical imaging. Treatment using radiation is known as radiotherapy.

See also Diagnostic Imaging and Conventional Radiography.

Tomography is imaging by sections or sectioning to obtain images of slices through objects like the human body. Tomography is derived from the Greek words 'to cut or section' (tomos) and 'to write' (graphein). A device used in tomography is called a tomograph, while the image produced is a tomogram.
The first medical applications utilized x-rays for images of tissues based on their x-ray attenuation coefficient. The mathematical basis for tomographic imaging was laid down by Johann Radon. This type of imaging is used in different medical applications as for example computed tomography, ultrasound imaging, positron emission tomography and magnetic resonance imaging (MRI) also called magnetic resonance tomography (MRT).
Conventional x-ray tomographic techniques show organ structures lying in a predetermined plane (the focal plane), while blurring the tissue structures in planes above and below by linear or complex geometrical motion of the x-ray tube and film cassette.
Basically, computed tomography is the reconstruction of an image from its projections. In the strict sense of the word, a projection at a given angle is the integral of the image in the direction specified by that angle. The CT images (slices) are created in the axial plane, while coronal and sagittal images can be rendered by computer reconstruction.

See also Zonography, Computed or Computerized Axial Tomography, Resolution Element, Radiographic Noise, Intravenous Pyelogram.