Increased frequency of pathologic findings on transcranial B-mode parenchymal sonography in patients with sporadic amyotrophic lateral sclerosis

Abstract

Although amyotrophic lateral sclerosis (ALS) is characterized by involvement of motor neurons in the motor cortex, brainstem and spinal cord, there is accumulating evidence that it is a multisystem degenerative disease, with dysfunction of the striatonigral dopaminergic system as well. Transcranial B-mode sonography of the parenchyma enables depiction of the differing tissue echogenicity of midbrain and basal ganglia structures in various movement disorders. Transcranial B-mode sonography was performed in the standard manner in 101 patients with sporadic newly diagnosed ALS and 60 age- and gender-matched controls. Increased frequencies of pathologic substantia nigra hyper-echogenicity (p = 0.027), interrupted brainstem raphe (p = 0.003) and increased third ventricle diameter (p < 0.0001) were detected in ALS patients as compared with healthy controls. Only four ALS patients exhibited some features of parkinsonism. Pathologic findings on transcranial B-mode sonography of parenchyma did not correlate with clinical presentation, functional status or disease subtype. Our study provides additional evidence of multisystem involvement in ALS patients, particularly in subcortical areas.

Keywords: Amyotrophic lateral sclerosis; Brainstem raphe; Substantia nigra; Third ventricle; Transcranial parenchymal sonography.