Longitudinal grey matter and metabolic contributions to cognitive changes in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis is characterized by rapidly evolving cognitive and brain impairments. While previous work revealed structural and functional alterations associated with cognitive decline in patients suffering from amyotrophic lateral sclerosis, the relationships between anatomo-functional changes and both disease’s progression and the evolution of cognitive performance remain largely unexplored. Here, we took advantage of repeated multi-modal acquisitions in patients with amyotrophic lateral sclerosis over 1 year to assess the longitudinal sequence of grey matter atrophy, glucose metabolism and cognitive changes. Results revealed metabolic and structural changes over frontal, thalamic and temporal regions. Both cortical hypermetabolism and hypometabolism (right temporal gyrus and right angular gyrus, respectively) were associated with cognitive performance and thalamic hypometabolism during the follow-up testing session. Furthermore, the inferior frontal gyrus atrophy mediated the relation between early hypometabolism in this region and the subsequent decline of the theory of mind abilities. Marked volume loss was associated with larger hypometabolism and impaired cognitive performance. To our knowledge, this is the first study to longitudinally examine both grey matter volume and metabolic alteration patterns in patients with amyotrophic lateral sclerosis, over a mean follow-up time of 1 year. We identify how changes of the inferior frontal gyrus critically underly later cognitive performance, shedding new light on its high prognostic significance for amyotrophic lateral sclerosis-related changes. These results have important implications for our understanding of structural and functional changes associated with amyotrophic lateral sclerosis and how they underly cognitive impairments.

Adult brainstem glioma presenting with isolated persistent hemifacial spasm or facial nerve palsy

OBJECT

Adult brainstem gliomas are a rare group of heterogeneous brain tumors. Classical clinical presentation includes progressive impairment of cranial nerves associated with long tract signs. The prognosis and response to treatment are poor; nevertheless, some patients do have a long survival. The objective of this study was to describe a series of patients with an isolated persistent hemifacial spasm and/or facial nerve palsy as the presenting symptom of a brainstem glioma.

METHODS

Fourteen patients from 3 French hospitals (Paris, Caen, Lille) were included. Clinical and radiological features and overall survival were retrospectively analyzed. A review of the literature of similar cases was performed.

RESULTS

Mean age at diagnosis was 35 years (range 19-57 years). Mean duration of facial nerve involvement before diagnosis was 17 months (range 1-48 months). Tumors were characterized on MRI by a lateralized location in the pons, a T1-weighted hyposignal, a T2-weighted hypersignal and no contrast enhancement after Gadolinium injection except for 2 cases. Biopsies were performed in 10 cases and showed 8 low-grade and 2 high-grade gliomas. All the patients were initially treated with radiotherapy and 6 patients with chemotherapy after progression. Eleven patients died from tumor progression. Median survival time was 90 months.

CONCLUSIONS

Adult brainstem gliomas revealed by a progressive isolated involvement of the facial nerve seem to have particular clinico-radiological features of slow progressive tumors and may be associated with long patient survival.

Longitudinal Study of Cognitive and Emotional Alterations in Amyotrophic Lateral Sclerosis: Clinical and Imaging Data

Objectives: Extra-motor manifestations occur in 50% of patients with amyotrophic lateral sclerosis (ALS). These mainly concern cognition, emotional processing and behavior. Depression and anxiety are less frequent. Little is known about how these manifestations change as the disease progresses. Similarly, although cortical thinning has been well-documented at disease onset, there are scant data about cortical thinning over time and how this correlates with extra-motor manifestations. The present study therefore assessed cognitive, emotional and psychological state and cortical thinning in a group of patients with ALS at baseline and after a follow-up period.

Methods: We assessed executive functions, facial emotion recognition, depressive and anxious symptoms, and cortical thinning in 43 patients with ALS at baseline, comparing them with 28 healthy controls, and 21 of them 9 months later. We looked for links among the extra-motor manifestations and correlations with cortical thickness.

Results: At baseline, patients had poor executive function and recognition of complex emotions from the eyes, and more anxious and depressive symptoms than controls. At follow-up, only inhibition abilities had worsened. Cortical thinning was observed in bilateral pre-central regions and other parts of the cerebral cortex at baseline. Over time, it worsened in motor and extra-motor areas. Executive functions correlated with thinning in the middle and inferior frontal gyrus and orbitofrontal cortex.

Conclusions: During follow-up, there was little deterioration in extra-motor manifestations and psychological state, despite continuing cortical thinning. Patients with affective Theory of Mind (ToM) changes seemed less depressed than the others. Impaired mental flexibility was subtended by prefrontal regions with cortical thinning.

Alexithymia in Amyotrophic Lateral Sclerosis and Its Neural Correlates

Introduction: Amyotrophic lateral sclerosis (ALS) is a severe neurodegenerative disease that causes progressive and extensive motor deficits. Patients may also have cognitive impairments or alteration of emotional processing. Very few studies, however, have looked at deficits in how they experience their own feelings (alexithymia).

Methods: We assessed alexithymia in 28 patients with ALS using the 20-item Toronto Alexithymia Scale (TAS-20), comparing them with a control group matched for sex, age, and education level. We took into account both the total score of the TAS-20 and its three subscores corresponding to the three dimensions of alexithymia: Difficulty Identifying Feelings (DIF), Difficulty Describing Feelings (DDF), and Externally Oriented Thinking (EOT). Patients also underwent a neuropsychological assessment and anatomical magnetic resonance imaging (MRI) in order to correlate cognitive performances and gray matter volume and level of alexithymia.

Results: On average, ALS subjects had a significantly higher total score and DIF sub-score of the TAS-20 than controls indicating an increased alexithymia in patients. Total and DIF Scores correlated significantly and negatively to gray matter volume of the prefrontal cortex, right superior temporal pole and parahippocampal gyri. No correlations were found between scores on executive functions and those on the TAS-20.

Conclusion: The first stage of one's own emotional processing seems to be affected in ALS independently of executive dysfunction. This trouble seems to be underpinned by cerebral regions that are well known to be both implicated in alexithymia in healthy subjects and altered in ALS.

Voxel-based mapping of grey matter volume and glucose metabolism profiles in amyotrophic lateral sclerosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive disease of the nervous system involving both upper and lower motor neurons. The patterns of structural and metabolic brain alterations are still unclear. Several studies using anatomical MRI yielded a number of discrepancies in their results, and a few PET studies investigated the effect of ALS on cerebral glucose metabolism. The aim of this study was threefold: to highlight the patterns of grey matter (GM) atrophy, hypometabolism and hypermetabolism in patients with ALS, then to understand the neurobehavioral significance of hypermetabolism and, finally, to investigate the regional differences between the morphologic and functional changes in ALS patients, using a specially designed voxel-based method. Thirty-seven patients with ALS and 37 age- and sex-matched healthy individuals underwent both structural MRI and 18[F]-fluorodeoxyglucose (FDG) PET examinations. PET data were corrected for partial volume effects. Structural and metabolic abnormalities were examined in ALS patients compared with control subjects using two-sample t tests in statistical parametric mapping (SPM). Then, we extracted the metabolic values of clusters presenting hypermetabolism to correlate with selected cognitive scores. Finally, GM atrophy and hypometabolism patterns were directly compared with a one-paired t test in SPM.

RESULTS

We found GM atrophy as well as hypometabolism in motor and extra motor regions and hypermetabolism in medial temporal lobe and cerebellum. We observed negative correlations between the metabolism of the right and left parahippocampal gyri and episodic memory and between the metabolism of right temporal pole and cognitive theory of mind. GM atrophy predominated in the temporal pole, left hippocampus and right thalamus, while hypometabolism predominated in a single cluster in the left frontal superior medial cortex.

CONCLUSIONS

Our findings provide direct evidence of regional variations in the hierarchy and relationships between GM atrophy and hypometabolism in ALS. Moreover, the 18FDG-PET investigation suggests that cerebral hypermetabolism is deleterious to cognitive function in ALS.

Neural substrate of cognitive theory of mind impairment in amyotrophic lateral sclerosis

We now know that amyotrophic lateral sclerosis (ALS) is not restricted to the motor system. Indeed, a large proportion of patients with ALS exhibit cognitive impairment, especially executive dysfunction or language impairment. Although researchers have recently turned their attention to theory of mind (ToM) in ALS, only five studies have been performed so far, and they reported somewhat contradictory results. Moreover, the neural basis of the potential ToM deficit in ALS remains largely unknown. The present study was therefore designed to clarify whether a cognitive ToM deficit is indeed associated with ALS, specify the putative link between cognitive ToM deficits and executive dysfunction in ALS, and identify the dysfunctional brain regions responsible for any social cognition deficits. We investigated cognitive ToM and executive functions in a group of 23 patients with ALS and matched healthy controls, using an original false-belief task and a specially designed battery of executive tasks. We also performed an (18)F-fluorodeoxyglucose positron emission tomography examination. Results confirmed the presence of cognitive ToM deficits in patients compared with controls, and revealed significant correlations between ToM and executive functions, although the cognitive ToM deficit persisted when a composite executive function score was entered as a covariate. Using statistical parametric mapping, we calculated positive correlations between tracer uptake and false-belief scores on a voxel-by-voxel basis in the patient sample. Results showed that the cognitive ToM deficit correlated with the dorsomedial and dorsolateral prefrontal cortices, as well as the supplementary motor area. Our findings provide compelling clinical and imaging evidence for the presence of a genuine cognitive ToM deficit in patients with ALS.

[Research in amyotrophic lateral sclerosis: what is new in 2009?]

This paper, written by French amyotrophic lateral sclerosis (ALS) center experts, presents an update of recent advances in fundamental, epidemiological and clinical research in ALS based on a review of the literature between September 2008 and November 2009. Among other pathophysiological mechanisms, the role of stress of the endoplasmic reticulum and the importance of energetic metabolic disturbances have been underscored. In the field of genetics, research has been advanced through the identification of mutations of the gene FUsed in Sarcoma/Translated in LipoSarcoma (FUS/TLS) in individuals with familial and sporadic ALS. This gene is involved in the regulation of transcription, splicing and RNA transport, and has functional homology to another ALS gene, TARDBP, which suggests that a common mechanism may underlie motor neuron degeneration. A report showed that mice expressing a mutant form of human TDP-43 develop a progressive and fatal neurodegenerative disease reminiscent of both ALS and frontotemporal lobar degeneration with ubiquitin aggregates (FTLD-U), providing a new animal model that may help to better understand the pathophysiology and test new therapeutics. Beside genetic studies, several epidemiologic studies have investigated the role of environmental factors. A recent study suggests that smoking is a risk factor for developing ALS and it is hypothesized that this could occur through lipid peroxidation via formaldehyde exposure. From a neuroprotective perspective, trials with IGF-1, sodium valproate, coenzyme Q or glatiramer acetate have failed to demonstrate any beneficial effect. A study published in 2008 argued that lithium may have a neuroprotective effect in ALS mice and also in patients. However, two preclinical studies failed to replicate the neuroprotective effect of lithium in ALS mice. Therapeutic trials have been performed or are currently ongoing in Europe and North America. Their results have not yet been published.

[Update on fundamental and clinical research in amyotrophic lateral sclerosis]

This paper from a group of French experts in amyotrophic lateral sclerosis (ALS) presents an update of recent advances in fundamental, epidemiological and clinical research in ALS. Recent development in the pathogenesis of ALS suggests that motor neuron degeneration is a multifactorial and noncell autonomous process. Research has been advanced through the identification of the TAR-DNA-binding protein (TDP-43) as a common neuropathological marker of ALS and frontotemporal lobar degeneration with ubiquitin-positive inclusions. Recently, mutations in the TDP-43 gene have been described in individuals with familial and sporadic ALS. Fundamental research in ALS is expected to lead to the disclosure of new diagnostic markers and therapeutic targets. A small trial has suggested that lithium carbonate may slow ALS progression but larger trials will be needed to confirm these results.

Causes of death amongst French patients with amyotrophic lateral sclerosis: a prospective study

BACKGROUND AND PURPOSE

To prospectively investigate causes of death and the circumstances surrounding death in 302 patients with amyotrophic lateral sclerosis (ALS). The functional status of patients immediately before death was also determined.

METHODS

Information was obtained from neurologists at ALS centres, patients' files, and, when deaths occurred outside a medical facility, attending physicians.

RESULTS

Most patients (63%) died in a medical facility. The most frequently reported cause of death was respiratory failure (77%), including terminal respiratory insufficiency (58%), pneumonia (14%), asphyxia due to a foreign body (3%) and pulmonary embolism (2%). Ten per cent of patients died from other causes: post-surgical or traumatic conditions (5%), cardiac causes (3.4%), suicide (1.3%) and sudden death of unknown origin (0.7%). The cause of death could not be determined in 13% of cases (6% inside a medical facility and 25% outside). At the time of death, only 55% of patients were receiving riluzole, 33% were undergoing non-invasive ventilation, 3% had a tracheotomy and 37% a gastrostomy.

CONCLUSION

The information provided by this study helps to improve our understanding of the natural history of the disease and may help optimize the quality of care we can offer patients at the end of life.

Test prédictif de Manktelow appliqué à l'utilisation de la toxine botulique

We are reporting the use of a xylocain test before the injection of botulinal toxin within the "facial paralysis and botulinal toxin" multidisciplinary consultation of the Caen regional hospital. Our assessment is about 16 patients tested. This test is based on a digital film and a questionnaire. It is often proposed when toxin is first used. It influences the patient's choice. It permits a better understanding of the toxin action by the patient, it reassures. It is reliable for the practitioner even though we do not have a mathematical correlation between the xylocain volume and the botulinal toxin volume. Simple and far, it is a help for the patient and the practitioner before a delicate injection of botulinal toxin.

Breast cancer and motor neuron disease: clinical study of seven cases

We report seven women, aged 52-78 years, with motor neuron disease (MND) associated with breast cancer. In five, cancer preceded MND by 30 years to 24 months, while in the remaining two it occurred from 8.5 years to one month after MND onset. Three patients were considered cured of their cancer at the time of the study. Four patients have died, one from associated colonic cancer, and three from MND. As in a previous report, the clinical pattern of MND in these patients was that of predominant upper motor neuron involvement in 6/7 cases. Three had frontotemporal dementia. No anti-neuronal antibodies were found. Although there is no recognized pathophysiological link between breast cancer and UMN-predominant MND we suggest there may be comorbidity between the two diseases.

[Lip kinetic disorders]

There are many lips kinetic disorders whose clinical appearances greatly differ. An acute examination directs toward the diagnosis on a neurologic, neurogenous, muscular, myogenous, medicamentous, dermatological or psychiatric etiology. The authors review the different etiologies that have to be discussed, in order to choose the appropriate further investigations and specialized examinations, before a possible surgical treatment.