To assess the impact of I-123 ioflupane single photon emission computed tomography (SPECT) imaging on classifying patients with striatal dopaminergic deficits. Sixty-one patients with an initial diagnosis of parkinsonism or uncertain tremor disorder were screened and followed-up for one year. All patients were re-examined by two neurologists at our centre and were classified as having neurodegenerative or non-neurodegenerative disorders. Patients underwent I-123 ioflupane SPECT imaging. SPECT studies were blindly evaluated and classified as normal or abnormal (indicative of neurodegenerative disorders). The overall agreement of the SPECT imaging results with the initial classification was 65.6% (kappa=0.229, p=0.074) but was 90.2% (kappa=0.782, p<0.001) with the classification of the neurologists at our centre. I-123 ioflupane SPECT imaging is a valuable method in the evaluation of patients presenting clinically with uncertain parkinsonian syndromes or for whom diagnostic doubt exists.