Clinical significance of reduced cerebral metabolism in multiple sclerosis: A combined PET and MRI study

Abstract

Magnetic resonance imaging (MRI) in patients with multiple sclerosis (MS) has provided major insights into the disease's natural history, and many studies have focussed on possible correlations between MRI findings and the clinical manifestations of MS. In contrast, there are few reports on possible relationships between functional imaging data and cognitive function. The present study assessed the relationship between clinical presentation and combined anatomical and functional imaging data in MS. Twenty patients with definite MS underwent MRI and positron emission tomography (PET) to evaluate cerebral blood flow (rCBF) and oxygen metabolism (rCMRO2). The relationships between these neuroimaging findings and clinical data, including the Expanded Disability Status Scale (EDSS), Mini-mental status scale, Hasegawa Dementia Scale and relapse time, were evaluated with Spearman's rank correlation coefficients. A general reduction in rCBF and rCMRO2 in the gray and white matter were found in the MS patients. EDSS was correlated with the number and size of the lesions on MRI and was negatively correlated with rCMRO2. A correlation between the decrease in rCMRO2 and the level of cognitive impairment was also found. The severity of cerebral hypometabolism was also related to the number of relapses. Morphological and functional findings obtained by MRI and PET are closely related to the clinical status in MS. Our results suggest that measurement of cerebral metabolism in MS has the potential to be an objective marker for monitoring disease activity and to provide prognostic information.

Concomitant Analysis of Arterial, Venous, and CSF Flows using Phase-Contrast MRI: A Quantitative Comparison Between MS Patients and Healthy Controls

“…29 Other possible underlying mechanisms were later suggested. Recent studies using MRI or metabolic PET studies 30,31 have highlighted a reduction of arterial inflow within the damaged white matter, particularly the periventricular normal-appearing white matter, 32,33 extending to the cerebral cortex and deep gray matter. Cerebral hypoperfusion in MS patients was mainly assumed to be secondary to reduced metabolic demand due to axonal degeneration.…”

Positron emission tomography with computed tomography imaging of neuroinflammation in experimental autoimmune encephalomyelitis

“…Our results also raise the question of whether this imaging modality can be of value in monitoring the presence of inflammatory infiltrates in the human autoimmune demyelinating disorder MS. Several [ 18 F]FDG PET imaging studies on MS have been published during the last 15 years (39)(40)(41)(42)(43)(44)(45). Interestingly, however, the goal of these studies was not to detect and monitor inflammation but rather to determine whether the regional cerebral metabolic rate of glucose (rCMRGlc) estimated by using [ 18 F]FDG PET can be used as an indirect measurement of cortical impairment in MS.…”

Characterizing Brain Oxygen Metabolism in Patients with Multiple Sclerosis with T2-Relaxation-Under-Spin-Tagging MRI

“…One study by Sun et al (1998), using positron emission tomography (PET), which requires specific tracer such as 15 O, has demonstrated that there is cerebral hypometabolism in both gray matter (GM) and white matter (WM) of MS patients. The severity of cerebral hypometabolism was also related to the number of relapses in patients, suggesting that the measurement of oxygen metabolism has a potential role in monitoring disease activity and prognosis.…”