1. Method implemented by a processing unit of a medical imaging analysis system for producing an estimate of a haemodynamic parameter on the basis of experimental intensity signals S(t), said estimation being carried out on the basis of an estimate {circumflex over (d)} a of a quantity of interest d of a dynamic artery/tissue/vein system of an elementary volume—referred to as a voxel—of an organ, said estimate comprising calculating {circumflex over (d)}=Ã −1 ·c, Ã −1 being a pseudo-inverse of a convolution matrix A and c describing a concentration curve of a contrast agent in said voxel, said concentration curve resulting from a prior conversion of said experimental signals, wherein the method further includes: a step ( 102 ) for breaking down A canonically into singular values in the form A=U·S·V T where S≡diag(σ 1 ,. .. , σ L ) is the diagonal matrix of singular values classified by increasing order, V T is the transpose of a matrix V, V=(V ij ) and U=(u ij ) are two unitary and real square matrices of dimension L×L, L≧N being a defined number of samples, {circumflex over (d)}, A and c respectively having dimensions L×1, L×L and L×1; at least one iterative step for: producing a pseudo-inverse Ã 1 −1 of A, in the form Ã 1 −1 =V·W l ·U T , U T designating the transpose of U with W l = diag ( 0 , … , 0  l , 1 / σ l + 1 , … , 1 / σ L ) 0 < ≤ L ; producing d l =Ã −1 ·c. a step for producing the estimate of the haemodynamic parameter on the basis of the estimate of the quantity of interest {circumflex over (d)}=d l F produced with the iteration l F , l F being positive and less than or equal to L.