Table 2.

¹H MR Spectroscopic findings in healthy children and adolescents

Investigators	Sample	MRS	Region(s) of interest	Metabolites/findings
van der Knaap et al. (1990)	1 mo – 16 yrs. mean = 5.9 yrs. (n = 41) no sedation	SV, 1.5 T 7 × 3 × 3 cm	paraventricular region, predominantly WM	-NAA/Cho and NAA/Cr increases with age -Cho/Cr decreases with age -Most rapid changes from 1 to 3 years
Kreis et al. (1993)	35 wks – 17.8 yrs. (n = 109 scans) healthy (18%) recovered infants (21%) cerebral pathology (61%) chloral hydrate	SV, 1.5 T 3–8 cm3 young 8–16 cm3 older	occipital cortex (GM) parieto-occipital (WM)	-Cr, myo-I increases until 2 yrs -NAA and Cho increases until 7 yrs.
Toft et al. (1994)	infants 259 – 295 days mean = 277 days (n = 8) adolescents 10 – 15 yrs. mean = 12.3 yrs. (n = 8) no sedation	SV, 1.5 T 2 cm3	infants: 1 voxel including caudate, putamen, globus pallidus adolescents: 4 voxels occipetal, basal ganglia, temporal, frontal. All voxels included GM and WM.	-NAA, PCr+Cr, Glu+/H2O higher in adolescents -Cho higher in infants -Inositols similar across groups
Pouwels et al. (1999)	0 – 18 yrs. (n = 97) healthy (8%) neuropediatric (92%) 18 – 39 yrs. (n = 72) <6 yrs. chloral hydrate	SV, 2.0 T 8–18 mL 8–18 mL 4–5 mL 4–6 mL 4–6 mL	parietal GM parieto-occipital WM cerebellum, vermis thalamus basal ganglia	-NAA increases in GM, cerebellum, thalamus with age up to 2 yrs, then stabilizes -NAA constant in WM, basal ganglia -Cr no change after 1 yr., highest level in cerebellum, followed by basal ganglia, thalamus, parietal GM, parieto-occipital WM -Cho declines in WM after 5 yrs
Choi et al. (2000)	3 – 14 yrs. mean = 9 yrs. (n = 30) young chloral hydrate	SV, 1.5 T 1.8 × 2 × 2 cm	allocortex (hippocampus, parahippocampal) isocortex (medial, frontal and parietal)	-NAA/Cr lower in allocortex than isocortex -Cho/Cr and mI/Cr higher in allocortex than isocortex -No age effects
Kadota et al. (2001)	4 – 88 yrs. mean=45.6 yrs. (n = 90) no sedation	CSI, 1.5 T 1.125 cm3	superior to corpus callosum, 12 voxels: 6 WM, 6 mesial GM, placed bilaterally in anterior, middle and, posterior regions	-NAA/Cho in WM rapidly increases until 10–20yrs. -NAA/Cho in WM declines starting in late 30s Laterality in males for NAA/Cho in WM -Steeper increase in WM NAA/Cho in males than in females -NAA/Cho in GM gradually declines linearly with age
Horska et al. (2002)	3 – 19 yrs. mean = 12.3 yrs. (n = 15) n = 2 nembutal	CSI, 1.5 T .8cm3	frontal, parietal (WM) basal ganglia (GM) thalamus (GM)	-NAA/Cho in GM peaks at 10 yrs. -NAA/Cho in WM increases with age
Costa et al. (2002)	3 – 18 yrs. (n = 37) no sedation	SV, 1.5T 8cm3	parieto-occipital WM cerebellar hemisphere	-NAA/Cr, Cho/Cr lower in cerebellum than parieto-occipital WM -NAA/H2O, Cr/H2O and Cho/H2O higher in the cerebellum than parieto-occipital WM -NAA/H2O increased with age in the cerebellum and parieto-occipital WM -Cho/H2O increased with age in the cerebellum
Goldstein et al. (2009)	6 – 18 yrs. (n = 105) no sedation	CSI, 1.5 T 1.5 × 1.5 × 2 cm	prefrontal cortex basal ganglia superior temporal cortex inferior parietal cortex centrum semiovale occipetal regions	-No significant differences in NAA between youngest (6–9.5 yrs.) vs. oldest (12–18 yrs.) group.
Raininko & Mattsson (2010)	13 – 72 yrs. (n=57) no sedation	SV, 1.5T 4 × 1.2 × 1.8 cm	supraventricular WM	-NAA increased with age -Glx showed U-shaped age dependance with highest concentrations in youngest and oldest subjects -No age dependence in Cho or Cr -No gender differences
Silveri et al. (2013)	12–14 yrs, (n = 30) 18–24 yrs. (n = 20) no sedation	SV, 4T 2 × 2 × 3 cm	anterior cingulate cortex parieto-occipetal cortex	-No differences between age groups for Cr -GABA/Cr lower in ACC but not POC in younger vs. older group -Gln/Glu lower in ACC but not POC in younger vs. older group

Abbreviations: SV, single voxel; CSI, chemical shift imaging; WM, white matter; GM, gray matter.

Note: Subjects in all studies were healthy, normally developing individuals except where noted otherwise. Findings reported in this table reflect healthy subjects only.