Investigating the role of 99mTc-TRODAT-1 SPECT imaging in idiopathic Parkinson's disease

Abstract

Objective: To investigate the role of 99mTc-TRODAT-1 SPECT in diagnosis and assessing severity of idiopathic Parkinson's disease (PD).

Methods: Thirty-eight patients with primary, tentative diagnosis of PD and eighteen age-matched normal controls were studied with 99mTc-TRODAT-1 SPECT imaging. The regions of interests (ROIs) were drawn manually on cerebellum (CB), occipital cortex (OC) and three transverse plane slice-views of striatums, the semiquantitative BG (background)/[(OC+CB)/2] were then calculated.

Results: A lower uptake of 99mTc-TRODAT-1 in striatums were displayed in thirty-six out of thirty-eight PD patients by visual inspection, compared to controls. In twenty-four PD cases with (Hoehn and Yahr scale) HYS stage I, a greater loss of DAT uptake was found in striatum and its subregions contralateral striatum to the affected limbs than in the same regions of the controls, although the striatal uptake was bilaterally reduced. Using Spearman correlation analysis showed that the reduction of the uptake ratios significantly correlated with the UPDRS in striatum and all its subregions in the PD group (P<0.05), a similar change was also found in the putamen by using the rating scale of Hoehn and Yahr (P<0.05). However, analysis of variance (ANOVA) did not show any relationship between the decreasing uptake of 99mTc-TRODAT-1 and increasing severity of PD patients, although the specific uptake of 99mTc-TRODAT-1 was continuously decreased in the striatum by visual inspection with the progress of PD from HYS stage I to III.

Conclusion: 99mTc-TRODAT-1 SPECT imaging may serve as a useful method for improving the correct diagnosis of PD. In assessing the role of 99mTc-TRODAT-1 SPECT in disease severity of PD, UPDRS can offer a comprehensive index, although the Hoehn and Yahr assessment may be available in part.

Fig. 1

^99mTc-TRODAT-1 SPECT in transverse views of normal controls and PD patients with HYS from stages I to III. A greater decline of DAT binding contralateral to more affected limbs was observed, although the striatal uptake was bilaterally reduced in PD cases with HYS stage I. A greater loss of DAT binding was noted in striatum by visual inspection in PD subjects with higher than lower HYS stage. (a) Control; (b) HYS stage I; (c) HYS stage II; (d) HYS stage III

Fig. 1

^99mTc-TRODAT-1 SPECT in transverse views of normal controls and PD patients with HYS from stages I to III. A greater decline of DAT binding contralateral to more affected limbs was observed, although the striatal uptake was bilaterally reduced in PD cases with HYS stage I. A greater loss of DAT binding was noted in striatum by visual inspection in PD subjects with higher than lower HYS stage. (a) Control; (b) HYS stage I; (c) HYS stage II; (d) HYS stage III

Fig. 1

^99mTc-TRODAT-1 SPECT in transverse views of normal controls and PD patients with HYS from stages I to III. A greater decline of DAT binding contralateral to more affected limbs was observed, although the striatal uptake was bilaterally reduced in PD cases with HYS stage I. A greater loss of DAT binding was noted in striatum by visual inspection in PD subjects with higher than lower HYS stage. (a) Control; (b) HYS stage I; (c) HYS stage II; (d) HYS stage III

Fig. 1

^99mTc-TRODAT-1 SPECT in transverse views of normal controls and PD patients with HYS from stages I to III. A greater decline of DAT binding contralateral to more affected limbs was observed, although the striatal uptake was bilaterally reduced in PD cases with HYS stage I. A greater loss of DAT binding was noted in striatum by visual inspection in PD subjects with higher than lower HYS stage. (a) Control; (b) HYS stage I; (c) HYS stage II; (d) HYS stage III

Fig. 2

The correlation of ^99mTc-TRODAT-1 uptake with UPDRS (a) and HYS stage (b), respectively. (a) The binding ratios of ^99mTc-TRODAT-1 displayed significant negative correlation with UPDRS in striatum, caudate and putamen, respectively; (b) The binding ratios were significantly correlated with HYS stage only in putamen

Fig. 2

The correlation of ^99mTc-TRODAT-1 uptake with UPDRS (a) and HYS stage (b), respectively. (a) The binding ratios of ^99mTc-TRODAT-1 displayed significant negative correlation with UPDRS in striatum, caudate and putamen, respectively; (b) The binding ratios were significantly correlated with HYS stage only in putamen