123I-FP-CIT in progressive supranuclear palsy and in Parkinson's disease: a SPECT semiquantitative study.
OBJECTIVE
It is still debated whether or not I-FP-CIT single photon emission computerized tomography (SPECT) is able to differentiate between Parkinson's disease and progressive supranuclear palsy (PSP). Our aim was to use SPECT semiquantitative analysis to assess the capacity of I-FP-CIT to characterize Parkinson's disease versus PSP.


METHODS
Twenty-one Parkinson's disease patients, 15 disease duration- and age-matched PSP patients and 20 age-matched healthy controls were included in this study. SPECT imaging was always performed at 4 h post-injection. The ratios of striatal (S) to non-specific occipital (O) binding for the entire striatum (S/O), caudate nuclei (C/O), putamina (P/O) were calculated in both the basal ganglia. The asymmetric index (AI) for the whole striatum was also calculated for Parkinson's disease and PSP.


RESULTS
Compared to healthy controls, S/O, C/O and P/O were significantly reduced (P<0.001) both in Parkinson's disease (-46%, -43%, -49%, contralaterally to the most affected side; -41%, -37%, -41%, ipsilaterally) and in PSP (-58%, -57%, -59%, contralaterally; -58%, -57%, -59%, ipsilaterally). S/O, C/O and P/O ratio values were significantly (P<0.001) lower in PSP patients when compared to Parkinson's disease group. The asymmetric index (AI) was significantly higher (P<0.001) in Parkinson's disease than in PSP (AI: 23.6%+/-15.07% vs. 9.66%+/-5.83), but with an overlap between the two groups.


CONCLUSIONS
Our results confirm that I-FP-CIT SPECT is clinically useful for detecting nigrostriatal degeneration both in Parkinson's disease and PSP. Moreover, in our series, semiquantitative analysis using I-FP-CIT SPECT allowed Parkinson's disease and PSP to be discriminated because PSP patients presented a more severe and symmetric dopamine transporter loss, and the results for S/O were more accurate.
Department of Biopathology, University "Tor Vergata", Rome, Italy.
Luca
L
Filippi
Carlo
C
Manni
Mariangela
M
Pierantozzi
Livia
L
Brusa
Roberta
R
Danieli
Paolo
P
Stanzione
Orazio
O
Schillaci
D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000000981:diagnostic imaging*; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013494:Supranuclear Palsy, Progressive / Q000000981:diagnostic imaging*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014326:Tropanes
D019275:Radiopharmaceuticals; D014326:Tropanes; C087552:2-carbomethoxy-8-(3-fluoropropyl)-3-(4-iodophenyl)tropane