SEPARATION OF WATER FROM FAT AT MAGNETIC RESONANCE TOMOGRAPHY Russian patent published in 2015 - IPC G01N24/08 

FIELD: physics.

SUBSTANCE: produced are two complex images I₁ and I₂ with different echo times wherein signals from fat and water are in phase and in counter phase, respectively. Phase 2φ of complex vector $$I^2={(I_2{I}_1^{*}/|I_1|)}^2$$ for every pixel of image matrix is calculated. Constructed is the matrix of developed phase 2φ and in the range of main magnitudes -180°…180° and defined is the sign of complex vector Ie^-iφu in matrix every pixel. Imaging for water is performed as the half-sum of absolute magnitude of image in phase and counter phase multiplied by sign Ie^-iφu, imaging of fat is made as half-difference of absolute magnitude of images of fat in phase and image in counter phase multiplied by the sign Ie^-iφu. Note here that estimated are averaged gradients of changes in phases of fat and water images by the formulae: G_F=(|I₁|-|I₂|)²/N_F at Ie^-iφu<0 G_W=(|I₁|-|I₂|)²/N_W at Ie^-iφu<0. Magnitudes G_F and G_W are compared. In case G_F<G_W, pixels of fat and water images are changed in places.

EFFECT: higher correctness of classification.

7 dwg