Mohammed T. Abou-Saleh

30 PRINCIPLES AND PRACTICE OF GERIATRIC PSYCHIATRYTable 7.2continuedStudy Subjects Imaging and measurement technique FindingsMurphy et al., 27 Healthy male volunteers, 19–92 years1992 45 old. No major medical, neurologic orpsychiatric illness. Handedness notspecifiedMR imaging (0.5 tesla). Blinded volumemeasurements using computer-assistedtrace methodology of proton densityaxial images (n=36, 7 mm thick, contiguous).Manual tracing of subcorticalfrom enhanced images. Rater reliabilitieswere established, but number of ratersnot reportedDoraiswamy et al.,1993 46 Same as Doraiswamy et al., 1992 MR imaging (1.5 tesla). Blinded linearmeasurements of interuncal distance onT 1 -weighted axial image (no additionaldetails provided)Raz et al.,1993a,b,c 47,48,4929 Healthy volunteers, 18–78 years old(43.8+21.5 years), 17 M, 12 F. Nohistory of medical, neurologic, orpsychiatric illness. All right-handedChristiansen et al.,1994 50 142 healthy volunteers, 21–80 yearsold, 78 M, 64 F. No major medicalor neurologic illnessCowell et al., 1994 51130 healthy volunteers (overlap withsubjects in Gur et al., 1991), 18–80 yearsold, 70 M, 60 F. No major medical,neurologic or psychiatric illness. Allright-handedDeCarli et al., 1994 52 30 Healthy male volunteers, 19–92 yearsold. No major medical, neurologic, orpsychiatric illness. 29 Right-handedPfefferbaum et al., 73 Healthy male volunteers (included in1994 53 Pfefferbaum et al., 1993), 21–70 years old(44.1+13.8 years). No major medical,neurologic, or psychiatric illness. Lefthanders included (n not specified)Soininen et al.,1994 54 32 Healthy volunteers from thecommunity, all with MMSE scores>25, 16 with age-associated memoryimpairment (AAMI) (67.7+7 years;4 M, 12 F), 16 controls (70.2+4.7 years;6 M, 10 F) without AAMI. All but oneright-handedMR imaging (0.3 tesla). Volumemeasurements using computer-assistedtrace methodology of digitized imagesfrom the films, by two blinded raters withhigh reliabilities. T 1 -weighted axial slices(n=9, 4.2 mm thick, 6.0 mm interscangap). T 2 -weighted coronal slices(n=17–21, 6.6 mm thick, 8.6 mminterscan gap)MR imaging (1.5 tesla). Area and volumemeasurements using computer-assistedtrace methodology of T 2 -weighted axialslices (n=15, 4 mm thick, 4 mm interscangap). Number of raters, their ‘blindness’and their reliabilities not specifiedOlder males (>60, n=17) had smallerratios of total, left, and right hemispherevolume to IV than younger males. Oldermales had smaller ratios of total caudatevolume to IV and of total lenticularnuclei volume to IV than younger males;no difference in ratio of total thalamusvolume to IV. Reductions in caudate andlenticular volumes also found when thevolumes were normalized to total brainvolume, suggesting a differential effect ofaging on these structures. Older malesexhibited a R>L asymmetry in lenticularnuclei; the reverse was true in youngermales.Age associated with larger interuncaldistance (NB: this measure was notcorrelated with amygdala volume ina follow-up study [Early et al., 1993]).Interactions with sex or laterality notreportedAfter controlling for head size, age associatedwith decreased volumes of caudateand visual cortex (females>males). Noassociation between age and volumes ofdorsolateral prefrontal cortex, anteriorcingulate gyrus, prefrontal white matter,hippocampal formation, postcentralgyrus, inferior parietal lobule or parietalwhite matterAge associated with decreased volume ofcerebral hemispheres. Interactions withsex or laterality not reportedMR imaging (1.5 tesla). Volume measurementsusing a combination of computer-Ratio of frontal lobe to IV was smaller inassisted trace methodology and pixelsegmentation of 3D images reconstructedfrom T 2 -weighted axial images (5 mmthick, contiguous). Good rater reliabilities,but ‘blindness’ not specifiedMR imaging (0.5 tesla). Volumemeasurements using computerassistedtrace methodology ofT 1 -weighted coronal images (6 mm thick,contiguous) through temporal lobe,by single (blind?) raterMR imaging (1.5 tesla). Blinded volumemeasurements derived from semi-automatedpixel segmentation of intermediateand T 2 -weighted axial images (n=17–20,5 mm thick, 2.5 mm interscan gap)MR imaging (1.5 tesla). Blinded volumemeasurements using computer-assistedtrace methodology of T 1 -weighted coronalimages (1 mm thick, contiguous)through temporal lobe, by single raterwith established reliabilitiesmales over 40 years old than in youngermales; no such group difference infemales. In contrast, the R>L asymmetryof frontal lobe to IV was larger inolder females than younger females; nosuch group difference in males. Ratio oftemporal lobe to IV was also smaller inmales over 40 years old than in youngermales; no such group difference infemales; no interactions with laterality.Ratio of the remaining brain volume toIV was smaller in older than youngersubjects for both sexes; no interactionswith lateralityAge associated with decreased ratio offrontal lobe volume to IV but not withtemporal lobe volume to IV. Nointeractions with lateralityAdjusting for head size, age associated withdecreased cortical gray matter volume(0.7 ml/year), but not with cortical whitematter volume. Interactions with lateralitynot reportedNo group differences in hippocampal volumes,although controls (but not AAMIsubjects) exhibited significant R>Lasymmetry. No group differences inamygdala volume or asymmetrycontinued