Motor neuron diseases (MND) are a group of pathologies in which motor neurons are selectively affected. Amyotrophic lateral Sclerosis (ALS) is a member of this group, affecting both upper (UMN) and lower motor neurons (LMN) [1].
ALS is a progressive neurodegenerative disease [1], with an estimated incidence in Caucasians of about 1,2-4,0 per 100,000 person-years [2]. ALS incidence increases with age, being more frequent between the 6th and 7th decades and in women more than men [3].
ALS aetiology is unknown in most cases; it is inherited in only 5-10% of cases (one third have SOD1, TARDBP and C9orf72 mutations) [1]. Similar mutations have been sporadically found in non-hereditary forms [1].
The diagnosis of ALS relays mostly …show more content…
Riluzole, an anti-glutamatergic drug that acts by blocking NMDA receptors, is proven to reduce the excitotoxicity in ALS, modestly improving the prognosis [13]; its combination with multidisciplinary care and respiratory support can slow clinical deterioration and improve life quality [1]. Regardless of these therapeutic interventions, only a minority of patients (5-10%) survive for a decade or more: ALS life expectancy is usually less than 3 years and respiratory failure is the main cause of dead [14, 15].
Currently there are no well-established biological markers of progression or prognosis, even though older age and bulbar-onset are considered worse prognosis factors [16].
During the past two decades an effort has been made to clarify pathophysiological mechanisms and to find new diagnostic methods in order to improve ALS dramatic prognosis. New neuroimaging techniques, allowing investigation of anomalies in micro-structure, biochemistry and neuronal networks in brain and spinal cord [17], have been uncovering important data about ALS pathophysiology.
The aim of this review is to present the advances in Magnetic Resonance Imaging applied to Amyotrophic Lateral Sclerosis for the past decade and to discuss its contribute to the knowledge about ALS pathophysiology and clinical course.
Materials and