title: Neuroimaging in the differential diagnosis of primary progressive aphasia - illustrative case series in the light of new diagnostic criteria.
abstract: BACKGROUND
  Primary progressive aphasia (PPA) is a progressive language disorder associated with atrophy of the dominant language hemisphere, typically left. Current PPA criteria divide PPA into three variants: non-fluent (nfvPPA), semantic (svPPA) and logopenic (lvPPA). The classification of PPA into one of the three variants may be performed at 3 levels: I) clinical, II) imaging-supported, III) definite pathologic diagnosis. This paper aimed at assessing the feasibility of the imaging-supported diagnostics of PPA variants in the Polish clinical setting with access to magnetic resonance imaging (MRI) and single-photon emission computed tomography (SPECT) examinations.
  
  
  METHODS
  We present the clinical and neuroimaging data on 6 patients (4 women, 2 men) clinically diagnosed with PPA (3 with nfvPPA and 3 with lvPPA) in whom MRI and SPECT were performed in order to determine if imaging-supported diagnosis could be established in those cases. In 4 individuals (2 with nfvPPA and 2 with lvPPA) clinical diagnosis was supported by neuroimaging (SPECT, albeit not MRI), thus level II of PPA diagnosis could be established in those cases. MRI results were either inconsistent with the clinical diagnosis (Patients 1 and 2) or a mixed pattern of atrophy was observed (Patients 3-6).
  
  
  CONCLUSIONS
  Imaging-supported diagnosis of PPA variant is more feasible with quantitative analysis of SPECT images than with purely qualitative visual analysis of MRI. Hypoperfusion abnormalities evidenced by SPECT are more variant-specific than patterns of atrophy.
authors.affiliation: Department of Neurology, St. Adalbert Hospital, Gdańsk, Poland ; Department of Neurological and Psychiatric Nursing, Medical University of Gdańsk, Gdańsk, Poland.
authors.forename: Emilia J
authors.initials: EJ
authors.lastname: Sitek
authors.affiliation: Department of Neurology, St. Adalbert Hospital, Gdańsk, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Narożańska
authors.affiliation: Department of Nuclear Medicine and Radiological Informatics, Medical University of Gdańsk, Gdańsk, Poland.
authors.forename: Bogna
authors.initials: B
authors.lastname: Brockhuis
authors.affiliation: Department of Radiology, St. Adalbert Hospital, Gdańsk, Poland.
authors.forename: Anna
authors.initials: A
authors.lastname: Muraszko-Klaudel
authors.affiliation: Department of Nuclear Medicine and Radiological Informatics, Medical University of Gdańsk, Gdańsk, Poland ; Faculty of Mathematics, Physics and Informatics, University of Gdańsk, Gdańsk, Poland.
authors.forename: Piotr
authors.initials: P
authors.lastname: Lass
authors.affiliation: Department of Clinical Psychology and Neuropsychology, Institute of Psychology, University of Gdańsk, Gdańsk, Poland.
authors.forename: Michał
authors.initials: M
authors.lastname: Harciarek
authors.affiliation: Department of Neurology, St. Adalbert Hospital, Gdańsk, Poland ; Department of Neurological and Psychiatric Nursing, Medical University of Gdańsk, Gdańsk, Poland.
authors.forename: Jarosław
authors.initials: J
authors.lastname: Sławek
keywords: Frontotemporal Dementia; Magnetic Resonance Imaging (MRI); Primary Progressive Aphasia; Single Photon-Emission Computerized Tomography (SPECT)