Embed Size (px)
Citation preview
Bimonthly Meeting on Oct. 10, 2008
Metabolic Concentrations and Ratios of Brain Tissue
Amarjeet Bhullar
We have compared metabolite ratios, calculated using different methods:
• Directly Generated by Functool [F1]
• Using Metabolites Concentration [F2]
• Gaussian Function Overlapped on metabolite peak with Baseline correction
• Gaussian Function Overlapped on metabolite peak with Baseline+Noise correction
Baseline Correction
Baseline corrects separately each individual spectral point in spectrumBy calculating and subtracting a Spline through each points for smoothing.
If smoothing width is non zero, takes its average value, which is very small =zero
In most of our spectrum baseline exists at zero
Baseline+Noise Correction
Metabolite ppm range Image range
Choline 3.16-3.32 67-77
Creatine 2.94-3.10 80-90
NAA 1.94-2.10 147-158
Lipid and lactate 1.50-0.90 187-221
Noise=Average value of after removing of four peaks
0.0
0.6
1.2
1.8
2.4
3.0
Cho/NAA
Met
abol
ite
Rat
ios
F1 F2 Baseline Corection Baseline+Noise Corection
Cho/Cr
V#20
50 100 150 200 250
0
200
400
Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
Voxel # 20, I0.4
50 100 150 200 250
0
200
400
Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
Voxel # 20, I0.4
0.0
0.6
1.2
1.8
2.4
3.0
Cho/NAA
Met
abol
ite
Rat
ios
F1 F2 Baseline Corection Baseline+Noise Corection
Cho/Cr
V#19
50 100 150 200 250
0
200
400
Real SpectrumS
ign
al (
MR
Un
its)
Image Number
Voxel # 19, I0.4
50 100 150 200 250
0
200
400
Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
Voxel # 19, I0.4
50 100 150 200 2500
300
600
900 Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
Voxel # 16, I0.4
50 100 150 200 2500
300
600
900 Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
Voxel # 16, I0.4
0.0
0.6
1.2
1.8
2.4
3.0
Cho/NAA
Met
abol
ite
Rat
ios
F1 F2 Baseline Corection Baseline+Noise Corection
Cho/Cr
V#16
Chemical Information on Voxel # 16, 19, 20
0.0
0.6
1.2
1.8
2.4
3.0
Cho/NAA
Met
abol
ite
Rat
ios
F1 F2 Baseline Corection Baseline+Noise Corection
Cho/Cr
V#26
50 100 150 200 2500
300
600
900
1200
Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
Voxel # 26, I0.4
50 100 150 200 2500
300
600
900
1200
Real SpectrumS
ign
al (
MR
Un
its)
Image Number
Voxel # 26, I0.4
50 100 150 200 2500
300
600
900
1200Voxel # 25, I0.4
Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
0.0
0.6
1.2
1.8
2.4
3.0
Cho/NAA
Met
abol
ite
Rat
ios
F1 F2 Baseline Corection Baseline+Noise Corection
Cho/Cr
V#25
50 100 150 200 2500
300
600
900
1200Voxel # 25, I0.4
Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
0.0
0.6
1.2
1.8
2.4
3.0
Cho/NAA
Met
abol
ite
Rat
ios
F1 F2 Baseline Corection Baseline+Noise Corection
Cho/Cr
V#24
50 100 150 200 250
-600
-400
-200
0
200
Real SpectrumSig
nal
(M
R U
nit
s)
Image Number
Voxel # 24, I0.4
50 100 150 200 250
-600
-400
-200
0
200
Real SpectrumSig
nal
(M
R U
nit
s)
Image Number
Voxel # 24, I0.4
Chemical Information on Voxel # 24, 25, 26
50 100 150 200 250-800
-600
-400
-200
0
Voxel # 31, I0.4
Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
0.0
0.6
1.2
1.8
2.4
3.0
Cho/NAA
Met
abol
ite
Rat
ios
F1 F2 Baseline Corection Baseline+Noise Corection
Cho/Cr
V#31
50 100 150 200 250-800
-600
-400
-200
0
Voxel # 31, I0.4
Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
0.0
0.6
1.2
1.8
2.4
3.0
Cho/NAA
Met
abol
ite
Rat
ios
F1 F2 Baseline Corection Baseline+Noise Corection
Cho/Cr
V#30
50 100 150 200 250
0
300
600
900
1200
Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
Voxel # 30, I0.4
50 100 150 200 250
0
300
600
900
1200
Real Spectrum
Sig
nal
(M
R U
nit
s)
Image Number
Voxel # 30, I0.4
0.0
0.6
1.2
1.8
2.4
3.0
Cho/NAA
Met
abol
ite
Rat
ios
F1 F2 Baseline Corection Baseline+Noise Corection
Cho/Cr
V#27
50 100 150 200 250
-200
0
200
400
600
Real Spectrum
Voxel # 27, I0.4
Sig
nal
(M
R U
nit
s)
Image Number50 100 150 200 250
-200
0
200
400
600
Real Spectrum
Voxel # 27, I0.4
Sig
nal
(M
R U
nit
s)
Image Number
Chemical Information on Voxel # 27, 30, 31
Metabolite Ratios Cho/Cre
0.0
0.4
0.8
1.2
1.6
2.0
Voxel #
Cho
/Cre
F1 F2 Our Calculation
I0.4
Conclusion:
There is no significant difference between our calculation and Functool.
Suggestions are welcome
