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Parametric Mapping is a way to measure relaxation time for longitudinal and transverse relaxation time along with extracellular volume. The Native T1 mapping or longitudinal (T1)  relaxation time is the time constant which determines the rate at which excited protons return to equilibrium. It is a measure of the time taken for spinning protons to realign with the external magnetic field. The T2 mapping or transverse (T2) relaxation time constant which determines the rate at which excited protons reach equilibrium or go out of phase with each other. It is a measure of the time taken for spinning protons to lose phase coherence among the nuclei spinning perpendicular to the main field. The term "native" means contrast niave in this context. the T2 measurement is only done prior to contrast.

"T1 mapping stands for registering the course of recovery of longitudinal magnetism", this means the relaxation time after either the preparation step (saturation or inversion prepulse) followed by the acquisition of images at several time points during the T1 recover/relaxation. T1 value represents the time when recovery of magnetism has reached a percentage of its original state (63%). The recovery rate relates to the myocardial tissue properties that may be altered by pathological tissue presence (https://www.ahajournals.org/doi/10.1161/circresaha.116.307974). T1 mapping values increase with disease, and decrease post contrast.

The following example shows the parametric mapping (T1 mapping, T2 mapping, and extracellular volume) results for USUBJID 301. For brevity, after contrast a limited sample of tests were shown in this example.

The PR dataset shows the procedure of cardiac magnetic resonance imaging using the device associated with SPDEVID ABC001 and the PRREFID of 12345678. This information shows what CMR device is used for the procedure and the accession number or procedure reference identifier associated with the specific procedure for USUBJID 301. The SPDEVID variable is used to relate records by the device (in this case, the CMR machine). The Device Identifier (DI) dataset holds the device information details, the Device Properties (DO) dataset holds characteristics of the device that do not vary over the between subjects. The Device-In-Use (DU) dataset holds settings that are set on a device when it is used and may vary between participants.

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