Gradientcorrected

Gradientcorrected is an adjective used to describe data, images, or signals that have been adjusted to compensate for distortions or biases caused by gradient fields or gradient-encoding schemes. The term is often hyphenated as gradient-corrected and may appear in metadata or methodological descriptions to indicate that a correction step has been applied.

In medical imaging, gradient correction typically refers to gradient nonlinearity correction in MRI. Gradient coils encode spatial information, but fields are not perfectly linear, producing geometric distortion and misregistration with anatomical references. Correction uses a precalibrated map of the gradient field or phantom measurements to re-map coordinates, yielding gradient-corrected images with improved geometric fidelity.

Outside imaging, gradient correction can mean removing linear trends associated with sensor gradients or baseline slopes in spectroscopy and other measurement techniques. In data processing pipelines, a gradientcorrected label signals that such corrections have been executed, aiding reproducibility. Software tools may implement gradient correction as part of preprocessing to standardize responses across the field of view.

Limitations include dependence on accurate gradient models and calibration data; residual distortions may remain, and overcorrection can introduce artifacts. The concept is often discussed together with gradient nonlinearity, geometric distortion correction, and related calibration procedures.

See also: gradient nonlinearity, geometric distortion correction.