The utility of cerebral perfusion SPECT analysis using SPM8, eZIS and vbSEE for the diagnosis of multiple system atrophy-parkinsonism

[Clinical and neuropsychological features and changes to regional cerebral blood flow in ‍patients with Parkinson's disease dementia]

This study aimed to clarify associations of clinical and neuropsychological features and change in regional cerebral blood flow (rCBF) on 123I-IMP-SPECT in patients with Parkinson's disease (PD) who developed dementia. Sixty-one PD patients (mean age, 65.9 ± 8.6 years; mean disease duration, 11.0 ± 11.0 years) were recruited and followed-up for two years. Clinical and neuropsychological characteristics, and rCBF from SPECT were compared between PD patients who developed dementia (PDD+) and those who remained undemented (PDD-). Thirty-eight PD patients (62.3%) were diagnosed with PD-MCI at baseline. During follow-up, 22 PD patients (36%) developed dementia (PDD+). Univariate logistic regression models showed that Hoehn and Yahr scale 4 (odds ratio [OR] 5.85; 95% confidence interval [CI] 1.35-30.75]), visual hallucination (OR 5.95; 95%CI 1.67-25.4]), and PD-MCI (OR 6.47; 95%CI 1.57-39.63]) represented a significant risk factor for PDD+. Among neuropsychological parameters, WAIS (Wechsler Adult Intelligence Scale)-III block design (OR 6.55; 95%CI 1.66-29.84), letter number sequencing (OR 7.01; 95%CI 1.65-36.64), digit-symbol coding (OR 3.90; 95%CI 1.13-14.2), Wechsler Memory Scale, revised (WMS-R) visual paired associates II (delayed recall) (OR 4.68; 95%CI 1.36-17.36), Logical memory I (immediate recall) (OR 8.30; 95%CI 1.37-90.89), Logical memory II (delayed recall) (OR 6.61; 95%CI 1.35-44.33), Visual reproduction I (immediate recall) (OR 7.67; 95%CI 2.11-31.40), and Visual reproduction II (delayed recall) (OR 5.64; 95%CI 1.62-21.47) were significant risk factors. Decreased rCBF assessed using the general linear model (two-sample t-test) by SPM8 was observed in the left precuneus (0, -66, 16), right cuneus (6, -76, 30), and left angular gyrus (-46, -74, 32) in PDD+ compared with PDD- patients. Collectively, we have here shown that clinical and neuropsychological characteristics as well as changes to rCBF in PD patients who converted to PDD+. These features should be carefully monitored to detect the development of dementia in PD patients.

Is multiple system atrophy with cerebellar ataxia (MSA-C) like spinocerebellar ataxia and multiple system atrophy with parkinsonism (MSA-P) like Parkinson's disease? - A saccade study on pathophysiology

OBJECTIVE

Patients with multiple system atrophy (MSA) are classified into those mainly manifesting cerebellar ataxia (MSA-C) and those mainly manifesting parkinsonism (MSA-P). Pathophysiological bases of these subtypes remain unclear. We hypothesized that MSA-C patients would resemble spinocerebellar degeneration patients and MSA-P patients would resemble Parkinson's disease (PD) patients in saccade abnormalities.

METHODS

We recorded visually guided and memory guided saccades (MGS) in 27 MSA-C and 15 MSA-P patients, as well as 50 age-matched normal subjects, 14 spinocerebellar degeneration patients showing pure cerebellar symptoms (SCD) and 61 Parkinson's disease (PD) patients.

RESULTS

Saccade parameters of both tasks showed similar changes with progressing disease in SCD and MSA-C patients, as did those of MSA-C and MSA-P patients, although hypometria was slightly more pronounced in MSA-P. In both subtypes of MSA, latency and success rate of MGS were stable throughout disease stages, whereas they deteriorated progressively with progressing disease in PD.

CONCLUSIONS

Pathophysiology underlying MSA-C and MSA-P is similar as viewed from saccade performance. The MGS performance in MSA was preserved. However, MSA-P patients showed more marked hypometria, suggesting a mixture of basal ganglia pathophysiology.

SIGNIFICANCE

The similarity of saccade performance between MSA-C and MSA-P may reflect common olivopontocerebellar pathology, while the direct pathway of the basal ganglia is relatively spared compared with PD, even in MSA-P.