UNLABELLED: The purpose of this study was to evaluate whether striatal morphology on a three-dimensional surface display of 123I-2beta-carbomethoxy-3beta-(4-iodophenyl)tropane (123I-beta-CIT) SPECT data can be used as a diagnostic index for Parkinson's disease. METHODS: We studied 11 patients with mild Parkinson's disease and 21 age-matched controls. Triple-head SPECT scans were acquired for 30 min at 20 h after injection of 123I-beta-CIT. We measured the vertical height of the caudate head (H) and the length of the long axis of the striatum (L) on the three-dimensional surface display generated from SPECT data. The morphometric index of the striatum was defined as L/H. The power of L/H to discriminate Parkinson's disease and control groups was evaluated by discriminant function analysis and was compared with that of region of interest (ROI)-based 123I-beta-CIT binding measurements (V"3) and their ratios. RESULTS: The mean L/H ratios (ipsilateral/contralateral) to the most affected limbs were (33%/45%) lower in the Parkinson's disease group compared with the control group, respectively. All other ROI-based measures confirmed that dopamine transporter reductions were most severe in the contralateral posterior putamen (a 68% reduction in V"3). In 1 patient with a subsequent clinical diagnosis of drug-induced parkinsonism, all SPECT measures were normal. The contralateral putamen contributed most to the discriminatory power, and the contralateral L/H showed the best discriminatory power of all SPECT measures. CONCLUSION: These results suggest that striatal morphology on a three-dimensional display of 123I-beta-CIT SPECT data provides information of diagnostic significance for Parkinson's disease. This morphometry can be done without requiring technically demanding ROI analysis, and thus this technique may be suitable for routine clinical use.
UNLABELLED: The purpose of this study was to evaluate whether striatal morphology on a three-dimensional surface display of 123I-2beta-carbomethoxy-3beta-(4-iodophenyl)tropane (123I-beta-CIT) SPECT data can be used as a diagnostic index for Parkinson's disease. METHODS: We studied 11 patients with mild Parkinson's disease and 21 age-matched controls. Triple-head SPECT scans were acquired for 30 min at 20 h after injection of 123I-beta-CIT. We measured the vertical height of the caudate head (H) and the length of the long axis of the striatum (L) on the three-dimensional surface display generated from SPECT data. The morphometric index of the striatum was defined as L/H. The power of L/H to discriminate Parkinson's disease and control groups was evaluated by discriminant function analysis and was compared with that of region of interest (ROI)-based 123I-beta-CIT binding measurements (V"3) and their ratios. RESULTS: The mean L/H ratios (ipsilateral/contralateral) to the most affected limbs were (33%/45%) lower in the Parkinson's disease group compared with the control group, respectively. All other ROI-based measures confirmed that dopamine transporter reductions were most severe in the contralateral posterior putamen (a 68% reduction in V"3). In 1 patient with a subsequent clinical diagnosis of drug-induced parkinsonism, all SPECT measures were normal. The contralateral putamen contributed most to the discriminatory power, and the contralateral L/H showed the best discriminatory power of all SPECT measures. CONCLUSION: These results suggest that striatal morphology on a three-dimensional display of 123I-beta-CIT SPECT data provides information of diagnostic significance for Parkinson's disease. This morphometry can be done without requiring technically demanding ROI analysis, and thus this technique may be suitable for routine clinical use.