Pad´e quantification of malignant and benign ovarian MRS data - Signal Processing in MRS with Biomedical Applications - page 299

CONVERGENCE of METABOLITE CONCENTRATIONS in FPT (−) ; BENIGN (Left), MALIGNANT (Right); FID LENGTH: N/M, N=1024, M=8−32

Metabolite Map for Concentrations: x (Input), o (Pade) Metabolite Map for Concentrations: x (Input), o (Pade)

10000 10000

B 0 ≈ 14.1T
N/32 = 32
FPT (−)

B 0 ≈ 14.1T
N/32 = 32
FPT (−)

Benign Malignant

Lac

5000 5000 Lac

(1.41 ppm,2603 µ M/L ww)

3000 3000

(1.41 ppm,6688 µ M/L ww)

2000 2000

1000 1000 Glc

(5.22,1387)

Gln

500 500

(2.47,823)

300 300

200 200

Gln

Glc

(2.47,270)

(5.22,260)

100 100

50 50

30 30

20 20

10 10

5 5

5 4 3 2 1.5 1 5 4 3 2 1.5 1

(i) Chemical shift (ppm) (iv) Chemical shift (ppm)

Metabolite Map for Concentrations: x (Input), o (Pade) Metabolite Map for Concentrations: x (Input), o (Pade)

10000 10000

B 0 ≈ 14.1T

N/16 = 64
FPT (−)

B 0 14.1T

N/16 = 64
FPT (−)

≈

Benign Malignant

Lac

5000 5000

Lac

(1.41 ppm,2479 µ M/L ww)

3000 3000 (1.41 ppm,6536 µ M/L ww)

2000 2000

Converged Converged

Ala

1000 1000 Glc

(1.51,586) Val

(5.22,1387) Ala

(1.04,395)

Gln

500 500

(1.51,293)

(2.47,828)

Lys

300 300

Val

(1.72,490)

200 200 Gln (1.04,113) Glc

Crn

Thr

Crn

(2.47,275)

(5.22,260)

(3.13,79) (1.33,248)

100 100

(3.13,68)
(3.05,63)

Lys

Cr Thr Cr

Iso

50

(1.72,101)

50

(1.33,90) (3.05,66)

Met

(1.02,79)

30 30

Cho (2.13,62)

20 20

Iso

(3.19,42)

(1.02,10)

Met

Cho

10

(2.13,7)

10

(3.19,15)

5 5

5 4 3 2 1.5 1 5 4 3 2 1.5 1

(ii) Chemical shift (ppm) (v) Chemical shift (ppm)

Metabolite Map for Concentrations: x (Input), o (Pade) Metabolite Map for Concentrations: x (Input), o (Pade)

10000 10000

B 0 ≈ 14.1T
N/8 = 128
FPT (−)

B 0 ≈ 14.1T
N/8 = 128
FPT (−)

Benign Malignant Lac

5000 5000

Lac

(1.41 ppm,2479 µ M/L ww)

3000 3000

(1.41 ppm,6536 µ M/L ww)

2000 2000

Converged Converged

Ala

1000 1000 Glc

(1.51,586) Val

(5.22,1387) Ala

(1.04,395)

Gln

500 500 (1.51,293)

(2.47,828)

Lys

300 300 Val

(1.72,490)

200 200 Gln

(1.04,113) Glc

Crn Thr

Crn

(2.47,275)

(5.22,260) (1.33,248)

(3.13,79)

100

(3.13,68)
(3.05,63)

100

Lys

Cr Thr Cr

Iso

50 50

(1.72,101) (1.33,90)

(3.05,66)

Met

(1.02,79)

30 30

(2.13,62)

Cho

20

Iso

20 (3.19,42)

Met (1.02,10)

Cho

10

(2.13,7)

10

(3.19,15)

5 5

5 4 3 2 1.5 1 5 4 3 2 1.5 1

(iii) Chemical shift (ppm) (vi) Chemical shift (ppm)

FIGURE 9.8
Convergence of the Padereconstructed concentrations of the metabolites for
the nonmalignant (left column) and cancerous (right column) ovarian cyst
data from [343]. At N/32 = 32, convergence has not yet been achieved (top
panels (i) and (iv)). At N/16 = 64, the reconstructed concentrations for all the
12 metabolites have converged (middle panels (ii) and (v)). This convergence
is stable at longer signal lengths on bottom panels (iii) and (vi) at N/8 = 128,
and beyond, as explicitly checked at N/4 = 256,N/2 = 512 and N = 1024.