[¹²³I]β‐CIT SPECT distinguishes vascular parkinsonism from Parkinson's disease

Abstract

We investigated whether [(123)I]-beta-CIT and single-photon emission computed tomography (SPECT) imaging distinguishes patients with clinically suspected vascular parkinsonism (VP) from patients with idiopathic Parkinson's disease (PD). [(123)I]beta-CIT SPECT is a sensitive marker of dopaminergic degeneration, and the degree of striatal binding reduction in PD correlates with disease severity. Thirteen patients who fulfilled rigid clinical criteria for VP (mean +/- S.D.: age, 76.5 +/- 5.3 years; disease duration, 3.6 +/- 2.8 years), 20 PD patients (age, 66.2 +/- 9.5 years; disease duration, 4.3 +/- 2.7 years), and 30 healthy persons (age, 44.6 +/- 19.2 years) underwent [(123)I]beta-CIT SPECT imaging. Age-corrected striatal beta-CIT binding was reduced on average by 40.8% in PD but was near normal in the VP group (mean reduction, 1.2%). This difference was statistically significant (Z = 4.68; P < 0.001). The left-right asymmetry of striatal beta-CIT binding was significantly increased in the PD group compared with normal controls and the VP group (F(2) = 17.4, P <0.001). Moreover, putamen-caudate nucleus ratios were significantly reduced in PD compared with both VP patients and healthy controls (F(2) = 65.5, P < 0.001). Whole striatal beta-CIT binding was more than one standard deviation above the mean PD values in all but one of the individual VP patients. Our findings suggest that the presynaptic dopaminergic deficits seen in PD are absent in most patients with VP. [(123)I]beta-CIT SPECT imaging may be useful to help distinguish between PD and VP patients during life.

SNM Practice Guideline for Dopamine Transporter Imaging with 123I-Ioflupane SPECT 1.0

“…Even then, a deficit from an infarct often gives a "punched-out" appearance, differing in morphology and quality from a typical presynaptic Parkinsonian syndrome deficit. If clarification is needed, a recent MRI scan should be reviewed (3,41,42). In psychogenic parkinsonism, current evidence suggests that 123 I-ioflupane binding is normal (7,15).…”

Nigrostriatal Dopamine Terminal Imaging with Dopamine Transporter SPECT: An Update

“…Reports on DAT binding in vascular PS provide heterogeneous results, which might indicate that vascular PS is a mixed entity that is not yet well characterized (40). Some authors have reported normal or only a slight but insignificant reduction of DAT binding in patients with suspected vascular PS (45,54,55); others have found significantly reduced binding values (56,57). This discrepancy may be attributed to differences in patient populations and the relatively small numbers of subjects investigated.…”

Practice Parameter: Diagnosis and prognosis of new onset Parkinson disease (an evidence-based review) [RETIRED]

“…Using clinical evaluation as the gold standard, five class III studies [35][36][37][38][39] demonstrated that IBZM or B-CIT SPECT had 8% to 100% specificity in identifying clinically diagnosed PD patients, as compared to other parkinsonian syndromes. Sensitivity varied from 30 to 100% (table E-4).…”