Results

Table 1 represents the four metabolite ratios calculated according to the anatomic region studied (Temporal Lobe or Frontal Lobe) and the Rivastigmine administration by the time the examination was performed (Week 0 or Week 16). NAA/Cr ratio at the RFL and NAA/mI levels at the LTL show significant differences after 16 weeks of Rivastigmine administration when Tukey test was applied for comparisons among ratio means with Bonferroni correction for small samples (p<0.05).

 

REGION OF INTEREST
NAA/Cr
mI/Cr
Cho/Cr
NAA/mI
RTL WEEK 0
1,89 ± 0,55
1,01 ± 0,23
0,74 ± 0,24
1,93 ± 0,62
RTL WEEK 16
1,40 ± 0,39
0,89 ± 0,47
0,92 ± 0,29
2,30 ± 1,79
         
LTL WEEK 0
2,03 ± 0,36
1,00 ± 0,36
0,77 ± 0,08
1,67 ± 0,51 †
LTL WEEK 16
1,88 ± 0,25
1,07 ± 0,42
0,74 ± 0,14
2,70 ± 1,21 †
 
RFL WEEK 0
1,46 ± 0,21 †
1,00 ± 0,33
0,79 ± 0,19
1,74 ± 0,73
RFL WEEK 16
1,96 ± 0,46 †
1,08 ± 0,29
0,84 ± 0,14
1,74 ± 0,38
 
LFL WEEK 0
1,97 ± 0,30
1,05 ± 0,31
0,94 ± 0,19
2,06 ± 0,78
LFL WEEK 16
1,90 ± 0,71
1,01 ± 0,18
0,84 ± 0,31
1,86 ± 0,40

Table 1
Summary of changes in metabolite ratios as an effect of Rivastigmine administration
RFL: Right Frontal Lobe. LFL: Left Frontal Lobe. RTL: Right Temporal Lobe. LTL: Left Temporal Lobe
† p< 0.05

 

Figure 3 shows MRS performed at the LTL in a moderate AD patient on week 0 (Left) and 16 weeks after Rivastigmine treatment (Right). It is clearly noticeable the significant change (p<0.05) in NAA/mI levels between the two observations. NAA/mI ratio increased from 0.99 (week 0) to 1.48 (week 16).

 

Figure 4 represents individual values of NAA/mI ratio measured at the LTL in moderate AD patients who participate in our study.

 

Figure 5 shows the correlation between MMSE changes and the increase of the NAA/mI ratio at the LTL in moderate AD patients treated with Rivastigmine for 16 weeks. r Spearman coefficient was = 0.94, p<0.004.

Figure 6 represents MRS performed at the RFL in a moderate AD patient on week 0 (Left) and 16 weeks after Rivastigmine treatment (Right). It is clearly noticeable the significant increase (p<0.05) in NAA/Cr levels between the two observations. NAA/Cr ratio changed from 1.35 (week 0) to 2.11 (week 16).

Figure 7 represents individual values for NAA/Cr ratio measured at the RFL in moderate AD patients who participate in the study.

Figure 8 shows the correlation between MMSE changes and the increase of the NAA/Cr ratio at the RFL in moderate AD patients treated with Rivastigmine for 16 weeks. r Spearman coefficient was 0.97, p<0.002.