Choline/NAA Spatial Variation

Lars Ewell

Radiation Oncology University of Arizona Medical Center

1/25/08

1

Cho/NAA Spatial VariationMetabolite Ratios for Different Tissue

0

0.51

1.5

2

2.53

3.5

44.5

5

1 2 3

Ratio

Cho/Cr

Cho/NAA

NAA/Cr

RadiationInduced Necrosis

WhiteMatter

RecurrentTumor

Cho/NAA has potential for necrosis/disease discrimination

Weybright et al., Neuroradiology (2004) 46: 541–549

Patient 1: Scanned 3/23/07

S26 S46

Patient 1, Cho/NAA 3/23/07

• Highest ratio near center of disease/radiation.

• Dark blue not zero, ambiguous, indeterminate spectra.

Patient 1, Cho/NAA 5/8/07

• Highest ratio moved posterior relative to 3/23/07 spectra.

• Dark blue not zero, ambiguous, indeterminate spectra.

Patient 1: Row and Columns1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

Cho/NAA Ratio: Spatial Variation - Row 11

0.00

0.20

0.40

0.60

0.80

1.00

0.00 1.00 2.00 3.00

Dist. from Inferior Slice (cm )

Cho

/NA

ACho/NAA Column 5

Cho/NAA Column 11

Cho/NAA Column 6

Cho/NAA Column 7

Cho/NAA Column 8

Cho/NAA Column 9

Cho/NAA Column 10

• Central Increase going from Inferior to Superior Slice: Columns 6, 7, 8

•Peripheral Decrease going from Inferior to Superior Slice: Columns 5, 10, 11

• Similar behavior for row number 12

Cho/NAA Ratio: Spatial Variation - Row 12

0.00

0.20

0.40

0.60

0.80

1.00

0.00 1.00 2.00 3.00

Dist. from Inferior Slice (cm )

Cho/

NAA

Cho/NAA Column 5

Cho/NAA Column 11

Cho/NAA Column 7

Cho/NAA Column 8

Cho/NAA Column 9

Cho/NAA Column 10

• Closer to lesion, different behavior Cho/NAA Ratio: Spatial Variation - Row 7

0.00

0.20

0.40

0.60

0.80

1.00

0.00 1.00 2.00 3.00

Dist. from Inferior Slice (cm )

Cho/

NAA

Cho/NAA Column 5

Cho/NAA Column11

Cho/NAA Column 6