In this recently published Italian paper, the imaging records of 13 patients diagnosed with PPFG (primary progressive freezing gait) were evaluated. Four of the patients had their diagnosis changed to PSP after the SPECT imaging scan (using a dopamine transporter) was found to be “abnormal,” and two patients with a “normal” scan had their diagnosis changed to CBD. In the US, SPECT scans are not widely available.
The abstract is below.
Parkinsonism & Related Disorders. 2012 Mar 27. [Epub ahead of print]
Nigro-striatal involvement in primary progressive freezing gait:
Insights into a heterogeneous pathogenesis.
Fasano A, Baldari S, Di Giuda D, Paratore R, Piano C, Bentivoglio AR,
Girlanda P, Morgante F.
Istituto di Neurologia, Università Cattolica del Sacro Cuore, Roma,
Italy; Department of Neuroscience, AFaR-Fatebenefratelli Association
for Biomedical Research, “San Giovanni Calibita-Fatebenefratelli”
Hospital, Isola Tiberina, Rome, Italy.
Primary progressive freezing gait (PPFG) is a clinical syndrome
underlain by diverse neurodegenerative diseases and characterized by
early occurrence of gait freezing. Either degeneration or integrity of
the nigrostriatal terminals have been found by SPECT and PET studies.
In this retrospective study, we evaluated (123)I-FP-CIT SPECT findings
in a consecutive series of 13 PPFG patients with detailed clinical
evaluation over time (mean follow-up duration: 3.1 ± 1.2 years). In
all patients, (123)I-FP-CIT SPECT has been performed at the time of
first clinical evaluation (1.7 ± 1.4 years after disease onset) and
was compared with data from 23 age- and sex-matched healthy subjects.
PPFG patients were categorized as having abnormal (n = 8) or normal (n
= 5) SPECT.
At disease onset, PPFG with abnormal SPECT had more frequent
hypophonia, higher UPDRS-III scores and partial levodopa
responsiveness. By contrast, PPFG with normal SPECT had more frequent
bilateral plantar responses and no response to levodopa.
At latest follow-up, initial diagnosis in the abnormal SPECT group was
revised (n = 5) to progressive supranuclear palsy (n = 4) and pure
akinesia with gait freezing (n = 1).
Among the five patients with normal SPECT, follow-up evaluation
disclosed corticobasal syndrome (n = 2) and primary lateral sclerosis
(n = 1). Dopamine transporter imaging can capture the clinical
heterogeneity of PPFG and might have a value to predict possible
Copyright © 2012 Elsevier Ltd. All rights reserved.
PubMed ID#: 22459564 (see pubmed.gov for the abstract only)