Clinical usefulness of dopamine transporter SPECT imaging with 123I-FP-CIT in patients with possible dementia with Lewy bodies: randomised study

Background Dementia with Lewy bodies (DLB) is underrecognised in clinical settings. Aims To investigate whether performing a I-123-ioflupane injection (I-123-FP-CIT also called DaTSCAN (TM)) single photon emission computed tomography (SPECT) scan in patients with possible DLB would lead to a more certain diagnosis (probable DLB or non-DLB dementia). Method We randomised 187 patients with possible DLB 2:1 to have a scan or not (control group). The outcome measure was a change in diagnosis to probable DLB or non-DLB. Results There were 56 controls and 114 scanned patients, of whom 43% had an abnormal scan. More patients in the imaging group had a change in diagnosis compared with controls at 8 and 24 weeks (61% (n =70) v. 4% (n =2) and 71% (n =77) V. 16% (n=9); both P<0.0001). Clinicians were more likely to change the diagnosis if the scan was abnormal (82%) than if it was normal (46%). Conclusions Imaging significantly contributed to a more certain diagnosis, proving to be a useful adjunct in the work-up of patients with possible DLB.