Impact of DaTscan Imaging on Clinical Decision Making in Clinically Uncertain Parkinson's Disease

The diagnosis of Parkinson's disease (PD) is primarily clinical, but in cases of diagnostic uncertainty, evaluation of nigrostriatal dopaminergic degeneration (NSDD) by imaging of the dopamine transporter using DaTscan with single-photon emission computed tomography (SPECT) brain imaging may be helpful.

In the current paper, we describe clinical scenarios for which DaTscan imaging was used in a prospective case series of 201 consecutive patients in whom a movement disorder specialist ordered DaTscan imaging to clarify NSDD. We describe the impact of DaTscan results on changing or confirming pre-DaTscan clinical diagnosis and on post-DaTscan treatment changes.

DaTscan imaging can be useful in several clinical scenarios to determine if NSDD is present. These include in patients with early subtle symptoms, suboptimal response to levodopa, prominent action tremor, drug-induced parkinsonism, and in patients with lower extremity or other less common parkinsonism clinical presentations. We also found DaTscan imaging to be useful to determine underlying NSDD in patients with PD diagnosis for 3-5 years but without apparent clinical progression or development of motor fluctuations. Overall, in 201 consecutive patients with clinically questionable NSDD, DaTscan was abnormal in 58.7% of patients, normal in 37.8%, and inconclusive in 3.5%. DaTscan imaging changed clinical diagnosis in 39.8% of patients and led to medication therapy changes in 70.1% of patients.