Fluorodeoxyglucose F18 positron emission tomography in progressive apraxia of speech and primary progressive aphasia variants.

Abstract

OBJECTIVES:

To determine patterns of hypometabolism on fluorodeoxyglucose F18 positron emission tomography (FDG-PET) in patients with progressive apraxia of speech (PAS) and primary progressive aphasia (PPA) variants and to use these patterns to further refine current classification.

DESIGN:

We identified all patients who had FDG-PET and PAS or PPA who were evaluated by an expert speech-language pathologist. Patterns of hypometabolism were independently classified by 2 raters blinded to clinical data. Three speech-language pathologists reclassified all patients into 1 of 7 operationally defined categories of PAS and PPA blinded to FDG-PET data.

SETTING:

Tertiary care medical center.

PATIENTS:

Twenty-four patients with PAS or PPA and FDG-PET.

MAIN OUTCOME MEASURE:

Fluorodeoxyglucose F18 PET hypometabolic pattern.

RESULTS:

Of the 24 patients in the study, 9 had nonfluent speech output; 14, fluent speech; and 1 was unclassifiable. Twenty-one patients showed FDG hypometabolism; the remaining 3 did not. Among the patients showing hypometabolism, 8 had a prerolandic pattern of which 7 had nonfluent speech including progressive nonfluent aphasia (n = 3), PAS (n = 1), and mixed nonfluent aphasia/apraxia of speech (n = 3); the other patient had PPA unclassifiable. The remaining 13 had a postrolandic pattern, all with fluent speech (P < .001), including logopenic progressive aphasia (n = 6), progressive fluent aphasia (n = 6), and semantic dementia (n = 1). Patterns of hypometabolism differed between the nonfluent variants and between the fluent variants, including progressive fluent aphasia.

CONCLUSION:

Patterns of FDG-PET hypometabolism support the clinical categorizations of fluency, the distinction of apraxia of speech from progressive nonfluent aphasia, and the designation of a progressive fluent aphasia category.

• Authors: Keith A Josephs, Joseph R Duffy, Tepanta R Fossett, Edythe A Strand, Daniel O Claassen, Jennifer L Whitwell, Patrick J Peller
• Journal: Archives of neurology (Arch Neurol) Vol. 67 Issue 5 Pg. 596-605 (May 2010) ISSN: 1538-3687 [Electronic] United States
• PMID: 20457960 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• Fluorodeoxyglucose F18

Topics

• Aged
• Aged, 80 and over
• Aphasia, Primary Progressive (diagnostic imaging, metabolism, physiopathology)
• Apraxias (diagnostic imaging, metabolism, physiopathology)
• Brain (diagnostic imaging, metabolism, physiopathology)
• Brain Mapping
• Cohort Studies
• Diagnosis, Differential
• Energy Metabolism (physiology)
• Female
• Fluorodeoxyglucose F18
• Functional Laterality (physiology)
• Humans
• Language Tests
• Male
• Middle Aged
• Positron-Emission Tomography
• Predictive Value of Tests