Being continuous, or having a continuous range of values.

(ADC) An analog to digital converter is used to bridge analog and digital circuitry. Medical imaging systems use an analog to digital converter to sample and quantize the image data.

An anaphylactic reaction is a generalized allergic effect (also called anaphylactic shock). Allergic or anaphylactoid reactions range from sneezing, urticaria and itching, bronchospasm, facial and laryngeal edema to life-threatening symptoms including cardiovascular collapse, shock and respiratory distress.
Iodinated contrast materials are safe and widely used. However, anaphylactoid reactions occur rarely after administration of x-ray contrast agents. Most hypersensitivity symptoms appear short time after the intravenous, oral, rectal or other application (e.g., retrograde pyelography), only few are delayed by hours.
Patients with a history of allergic, asthmatic or reactions to contrast agents are at increased risk of anaphylaxis. Pre-treatment with corticosteroids and antihistamines decreases the incidence of an adverse reaction.

Anatomy is the knowledge of human body and includes the exact form, position, size and relationship of anatomic structures like e.g., bones, organs, nerves and other tissues.

H.O. Anger developed the first gamma camera in 1957; introduced in 1958 it was made of a gunsight collimator, one NaJ crystal and seven vacuum tube photomultipliers.

See Gamma Camera.