Correlation between clinical symptoms and striatal DAT uptake in patients with DLB

Abstract

In patients with DLB, only parkinsonism is associated with a reduction in striatal DAT uptake.

Clinical imaging in dementia with Lewy bodies

“…Three of the 30 pathologically confirmed DLB subjects however had normal DAT scans, but these patients were found to have minimal pathology in the brain stem (with predominantly neocortical or limbic Lewy bodies) and had presented with fluctuations and visual hallucinations,19 suggesting DLB patients with minimal brainstem Lewy bodies and therefore minimal parkinsonism maybe missed. Indeed, a negative correlation between the severity of parkinsonism and DAT uptake in the striatum has been reported in patients with DLB, with no correlation with the other core features of DLB 20. There were also three false-negative DAT scans in the recent postmortem study, from patients who had AD clinically at the time of their scan, but developed DLB symptoms in the years afterwards, suggesting Lewy body pathology was not present at the time of the scan, but may have developed later, leading to mixed AD/DLB ultimately 19…”

Role of Neuroimaging on Differentiation of Parkinson’s Disease and Its Related Diseases

“…In some cases, the clinical differentiation of patients with AD from those with DLB may be diffi cult because of overlapping clinical and pathological features. 6 Conventional MR imaging shows focal volume loss classically starting in the entorhinal cortex, involving the medial temporal lobe and hippocampus, as well as the parietal lobe in AD. 51 NmMRI shows no reduction in signal intensity in the substantia nigra in AD, while a signal reduction in the substantia nigra is prominent in patients with PD and DLB.…”

“…51,52 Recent studies have indicated that MIBG myocardial scintigraphy provides diagnostic information that is useful for differentiating DLB from AD. 6 Moreover, the combination of DaTSCAN and MIBG myocardial scintigraphy may provide a powerful differential diagnostic tool when it is difficult to differentiate patients with DLB from those with AD using DaTSCAN or MIBG myocardial scintigraphy alone. 6 (Fig.…”

“…6 Moreover, the combination of DaTSCAN and MIBG myocardial scintigraphy may provide a powerful differential diagnostic tool when it is difficult to differentiate patients with DLB from those with AD using DaTSCAN or MIBG myocardial scintigraphy alone. 6 (Fig. 9) Although the gold standard for the diagnosis of PD and its related neurodegenerative diseases is a postmortem neuropathological examination 27 , the diagnosis of these diseases is still largely based on the correct identifi cation of their clinical features.…”

“…4,5 Moreover, difficulties are sometimes associated with the clinical differentiation of patients with parkinsonism from those with Alzheimer's disease (AD) because of overlapping clinical and pathological features. 2,6,7 In spite of recent advances in the imaging and genetics of parkinsonian disorders, the diagnosis of PD remains a primarily clinical exercise. In an attempt to target this pitfall, numerous ancillary investigations have been developed in the last decade to support a PD diagnostic work-up.…”