Babak Fallahi1, Atefe Esmaeili1, Davood Beiki2, Shahram Oveisgharan3, Hamid Noorollahi-Moghaddam3, Mostafa Erfani4, Abbas Tafakhori5, Mohammad Rohani6, Armaghan Fard-Esfahani1, Alireza Emami-Ardekani1, Parham Geramifar1, Mohammad Eftekhari1. 1. Research Center for Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, North Kargar Ave., Tehran, 1411713135, Iran. 2. Research Center for Nuclear Medicine, Shariati Hospital, Tehran University of Medical Sciences, North Kargar Ave., Tehran, 1411713135, Iran. beikidav@sina.tums.ac.ir. 3. Department of Neurology, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran. 4. Radiation Application Research School, Nuclear Science and Technology Research Institute, Tehran, Iran. 5. Department of Neurology, School of Medicine, Imam Khomeini Hospital and Iranian Center of Neurological Research, Tehran University of Medical Sciences, Tehran, Iran. 6. Department of Neurology, School of Medicine, Rasoul Akram Hospital, Iran University of Medical Sciences, Tehran, Iran.
Abstract
OBJECTIVE: Parkinson disease (PD), parkinsonian syndromes (PS) and essential tremor (ET) are different types of movement disorders which share some symptoms resulting in a difficulty of certain diagnosis. This study was conducted to determine the value of (99m)Tc-TRODAT-1 scan to differentiate PD from ET and other PS cases. METHODS: Totally, 75 patients were studied including 29 PD, 6 possible PD, 22 ET and 18 PS cases. A dual-head SPECT-CT was used to perform basal ganglia (BG) imaging following administration of (99m)Tc-TRODAT-1. The BG uptake values were normalized to whole brain and occipital activity. All patients were followed for 2-22 months to reach a certain diagnosis. RESULTS: Patients with ET and drug-induced parkinsonism show significantly higher normalized BG uptake as compared to the other subgroups; however, no significant difference was noted between PD and PS patients. The sensitivity and specificity of the findings for the differentiation between patients with the disease associated versus not associated with BG dysfunction were 80 and 83.3%, respectively. A predictive positive value of 82.6% was obtained using an additive scaling index defined as asymmetry and unevenness of uptake in putamen and/or caudate contralateral to the dominant side of current symptoms. CONCLUSIONS: (99m)Tc-TRODAT-1 scan is an appropriate method to differentiate PD or PS versus ET. A combination of scan pattern including asymmetry of BG uptake and unevenness of activity in caudate and putamen along with the side of dominant symptoms may be valuable for the differentiation of Parkinson's disease from the other parkinsonian syndromes.
OBJECTIVE:Parkinson disease (PD), parkinsonian syndromes (PS) and essential tremor (ET) are different types of movement disorders which share some symptoms resulting in a difficulty of certain diagnosis. This study was conducted to determine the value of (99m)Tc-TRODAT-1 scan to differentiate PD from ET and other PS cases. METHODS: Totally, 75 patients were studied including 29 PD, 6 possible PD, 22 ET and 18 PS cases. A dual-head SPECT-CT was used to perform basal ganglia (BG) imaging following administration of (99m)Tc-TRODAT-1. The BG uptake values were normalized to whole brain and occipital activity. All patients were followed for 2-22 months to reach a certain diagnosis. RESULTS:Patients with ET and drug-induced parkinsonism show significantly higher normalized BG uptake as compared to the other subgroups; however, no significant difference was noted between PD and PS patients. The sensitivity and specificity of the findings for the differentiation between patients with the disease associated versus not associated with BG dysfunction were 80 and 83.3%, respectively. A predictive positive value of 82.6% was obtained using an additive scaling index defined as asymmetry and unevenness of uptake in putamen and/or caudate contralateral to the dominant side of current symptoms. CONCLUSIONS: (99m)Tc-TRODAT-1 scan is an appropriate method to differentiate PD or PS versus ET. A combination of scan pattern including asymmetry of BG uptake and unevenness of activity in caudate and putamen along with the side of dominant symptoms may be valuable for the differentiation of Parkinson's disease from the other parkinsonian syndromes.