Aim. Previous positron emission tomography (PET) [F-18]fluorodeoxyglucose ([F-18]FDG) studies in Parkinson's disease (PD) demonstrated that moderate to late stage patients display widespread cortical hypometabolism, whereas early stage PD patients exhibit little or no cortical changes. However, recent studies suggested that conventional data normalization procedures may not always be valid, and demonstrated that alternative normalization strategies better allow detection of low magnitude changes. We hypothesized that these alternative normalization procedures would disclose more widespread metabolic alterations in de novo PD. Methods. [F-18]FDG PET scans of 26 untreated de novo PD patients (Hoehn & Yahr stage I-II) and 21 age-matched controls were compared using voxel-based analysis. Normalization was performed using gray matter (GM), white matter (WM) reference regions and Yakushev normalization. Results. Compared to GM normalization, WM and Yakushev normalization procedures disclosed much larger cortical regions of relative hypometabolism in the PD group with extensive involvement of frontal and parieto-temporal-occipital cortices, and several subcortical structures. Furthermore, in the WM and Yakushev normalized analyses, stage II patients displayed more prominent cortical hypometabolism than did stage I patients. Conclusion. The use of alternative normalization procedures, other than GM, suggests that much more extensive cortical hypometabolism is present in untreated de novo PD patients than hitherto reported. The finding may have implications for our understanding of the basic pathophysiology of early-stage PD.

Alternative normalization methods demonstrate widespread cortical hypometabolism in untreated de novo Parkinson's disease / Berti V; Polito C; Borghammer P; Ramat S; Mosconi L; Vanzi E; De Cristofaro MT; De Leon M; Sorbi S; Pupi A. - In: THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING. - ISSN 1824-4785. - STAMPA. - 56:(2012), pp. 299-308.

Alternative normalization methods demonstrate widespread cortical hypometabolism in untreated de novo Parkinson's disease.

BERTI, VALENTINA;RAMAT, SILVIA;MOSCONI, LISA;SORBI, SANDRO;PUPI, ALBERTO
2012

Abstract

Aim. Previous positron emission tomography (PET) [F-18]fluorodeoxyglucose ([F-18]FDG) studies in Parkinson's disease (PD) demonstrated that moderate to late stage patients display widespread cortical hypometabolism, whereas early stage PD patients exhibit little or no cortical changes. However, recent studies suggested that conventional data normalization procedures may not always be valid, and demonstrated that alternative normalization strategies better allow detection of low magnitude changes. We hypothesized that these alternative normalization procedures would disclose more widespread metabolic alterations in de novo PD. Methods. [F-18]FDG PET scans of 26 untreated de novo PD patients (Hoehn & Yahr stage I-II) and 21 age-matched controls were compared using voxel-based analysis. Normalization was performed using gray matter (GM), white matter (WM) reference regions and Yakushev normalization. Results. Compared to GM normalization, WM and Yakushev normalization procedures disclosed much larger cortical regions of relative hypometabolism in the PD group with extensive involvement of frontal and parieto-temporal-occipital cortices, and several subcortical structures. Furthermore, in the WM and Yakushev normalized analyses, stage II patients displayed more prominent cortical hypometabolism than did stage I patients. Conclusion. The use of alternative normalization procedures, other than GM, suggests that much more extensive cortical hypometabolism is present in untreated de novo PD patients than hitherto reported. The finding may have implications for our understanding of the basic pathophysiology of early-stage PD.
2012
56
299
308
Berti V; Polito C; Borghammer P; Ramat S; Mosconi L; Vanzi E; De Cristofaro MT; De Leon M; Sorbi S; Pupi A
File in questo prodotto:
File Dimensione Formato  
QJNM_2012_Normalization_FDG_PD.pdf

Accesso chiuso

Tipologia: Pdf editoriale (Version of record)
Licenza: Tutti i diritti riservati
Dimensione 2.5 MB
Formato Adobe PDF
2.5 MB Adobe PDF   Richiedi una copia

I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificatore per citare o creare un link a questa risorsa: https://hdl.handle.net/2158/643962
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 15
  • ???jsp.display-item.citation.isi??? 15
social impact