PMID- 12414259
OWN - NLM
STAT- MEDLINE
DCOM- 20030213
LR  - 20220418
IS  - 1053-8119 (Print)
IS  - 1053-8119 (Linking)
VI  - 17
IP  - 3
DP  - 2002 Nov
TI  - Statistical parametric mapping of (99m)Tc-HMPAO-SPECT images for the diagnosis of 
      Alzheimer's disease: normalizing to cerebellar tracer uptake.
PG  - 1193-202
AB  - BACKGROUND: For a quantitative comparison of images obtained during 
      (99m)Tc-hexamethylpropylene amine oxime (HMPAO) single-photon emission computed 
      tomography (SPECT), brain activity values are usually normalized to a reference 
      region. In studies of Alzheimer-type dementia (ATD), the cerebellum is often used 
      as a reference region, assuming that it is spared any major pathological 
      involvement. Statistical parametric mapping (SPM) may enhance the evaluation of 
      SPECT scans in ATD patients. However, current SPM software only allows scaling to 
      average whole brain activity (i.e., global normalization). The aim of this study 
      was to develop an easily applied, objective, and reproducible method for 
      determining average cerebellar tracer uptake so that images can be scaled 
      specifically to cerebellar activity prior to the performance of SPM analysis. We 
      also investigated whether cerebellar normalization increases the sensitivity and 
      specificity of SPM analysis of ATD patients compared with global normalization. 
      METHODS: Image files were taken from a parallel study investigating the use of 
      SPECT as a diagnostic tool for early onset of ATD. Two methods for determining 
      cerebellar activity were developed: one manually, using templates, the other 
      automated, using specified coordinates entered into a Matlab routine. Group 
      comparison of ATD patients versus controls (= healthy volunteers and depressed 
      patients) was performed on a voxel-by-voxel basis using SPM 96 on Windows 95. 
      Receiver operator characteristics (ROC) were computed for 20 student raters 
      examining patient and control scans with and without single-subject SPMs. 
      RESULTS: The reduction of cerebral blood flow in the group of ATD patients 
      appeared 1.7 times greater in spatial extent when the tracer uptake was 
      normalized to cerebellum rather than to average whole brain activity. Computing 
      the reverse contrast (reductions in the control group compared with ATD patients) 
      produced clusters of significance in globally normalized images which were not 
      manifest after normalizing to cerebellum. This is consistent with the notion that 
      the cerebellum is spared in ATD. Analysis of the area under the ROC curve showed 
      that cerebellar-normalized SPM produced significantly improved accuracy over 
      perfusion scans alone. CONCLUSION: An easily applied, objective, reproducible 
      method was developed for normalizing images to cerebellum prior to the 
      performance of SPM analysis. Cerebellar normalization produced more extensive 
      abnormalities in SPM analyses of ATD patients than global normalization. 
      Furthermore, cerebellar normalization produced marginally more accurate 
      diagnostic results in single-scan SPM analysis of ATD patients than did global 
      normalization.
FAU - Soonawala, Darius
AU  - Soonawala D
AD  - Department of Psychiatry, University of Edinburgh, Kennedy Tower, Royal Edinburgh 
      Hospital, Morningside Park, Edinburgh EH10 5HF, United Kingdom.
FAU - Amin, Tania
AU  - Amin T
FAU - Ebmeier, Klaus P
AU  - Ebmeier KP
FAU - Steele, J Douglas
AU  - Steele JD
FAU - Dougall, Nadine J
AU  - Dougall NJ
FAU - Best, Jonathan
AU  - Best J
FAU - Migneco, Octave
AU  - Migneco O
FAU - Nobili, Flavio
AU  - Nobili F
FAU - Scheidhauer, Klemens
AU  - Scheidhauer K
LA  - eng
PT  - Journal Article
PL  - United States
TA  - Neuroimage
JT  - NeuroImage
JID - 9215515
RN  - 3B744AG22N (Technetium Tc 99m Exametazime)
SB  - IM
MH  - Aged
MH  - Aged, 80 and over
MH  - Alzheimer Disease/*diagnostic imaging/psychology
MH  - Brain/*diagnostic imaging
MH  - Brain Mapping/*methods
MH  - Cerebellum/diagnostic imaging
MH  - Depressive Disorder/diagnostic imaging/psychology
MH  - Female
MH  - Humans
MH  - Image Processing, Computer-Assisted/*statistics & numerical data
MH  - Male
MH  - Mathematical Computing
MH  - Mental Status Schedule
MH  - Middle Aged
MH  - ROC Curve
MH  - Reference Values
MH  - Reproducibility of Results
MH  - Technetium Tc 99m Exametazime
MH  - Tomography, Emission-Computed, Single-Photon/*statistics & numerical data
EDAT- 2002/11/05 04:00
MHDA- 2003/02/14 04:00
CRDT- 2002/11/05 04:00
PHST- 2002/11/05 04:00 [pubmed]
PHST- 2003/02/14 04:00 [medline]
PHST- 2002/11/05 04:00 [entrez]
AID - S1053811902912590 [pii]
AID - 10.1006/nimg.2002.1259 [doi]
PST - ppublish
SO  - Neuroimage. 2002 Nov;17(3):1193-202. doi: 10.1006/nimg.2002.1259.