Cortical involvement in four cases of primary lateral sclerosis using [11C]-flumazenil PET

Abstract

Four PLS patients underwent cerebral [(11)C]-flumazenil PET. They were compared firstly with a group of controls, then later directly with a group of sporadic ALS patients and a familial ALS group homozygous for the 'D90A' SOD1 gene mutation. There was a similar pattern of decreased binding in PLS patients when compared to controls as that seen in a previous study of sporadic ALS patients, supporting the concept that PLS is part of the same overall spectrum of MND. However, in direct group comparisons, both sporadic and homD90A ALS patients demonstrated relative decreases in anterior and orbito-frontal binding compared to PLS patients, suggesting that there may be differences in cortical vulnerability between phenotypic groups.

Whole brain‐based analysis of regional white matter tract alterations in rare motor neuron diseases by diffusion tensor imaging

“…Supportive laboratory tests merely help to exclude other diseases [Singer et al, 2007]. In some cases, focal atrophy of the precentral gyrus and thinning of the motor cortex on magnetic resonance imaging (MRI) [Butman and Floeter, 2007], and decreased glucose consumption in pericentral regions on positron emission tomography (PET) scan have been observed [Turner et al, 2007]. Magnetic resonance spectroscopy ( 1 H MRS) studies revealed reduced metabolite ratios in PLS patients compared to controls, suggesting dysfunction or loss of neurons in the motor cortex.…”

The Stripe of Primary Lateral Sclerosis

“…11 Primary motor cortex involvement is confirmed on serial magnetic resonance imaging, 12 magnetic resonance spectroscopy, 13 [ 11 C]flumazenil (cortical binding compound) PET, 7 and FDG-PET. 6 Patients with ALS seem to have more diffuse frontal cortical hypometabolism as evidenced by both [ 14 Therefore, it is reasonable to conjecture that pure PLS should primarily affect the primary motor cortex.…”

“…5 In PLS, functional neuroimaging can highlight selective upper motor neuron degeneration in areas such as the pericentral cortex 6 or primary motor cortex. 7 However, functional imaging studies such as positron emission tomography (PET) are not always interpreted uniformly. 8 In clinical practice, fluorodeoxyglucose F18 (FDG) is used to evaluate regional cerebral glucose metabolism.…”

Amyotrophic Lateral Sclerosis

“…Comparative studies in PLS revealed preservation of inhibitory infl uences frontally (Turner et al 2007a ), in keeping with the generally lower incidence of overt cognitive impairment in this group.…”