Cerebral venous circulatory system evaluation by ultrasonography - "The aim of this paper is to show the possibilities of intracranial and extracranial ultrasound evaluation of the head and neck venous circulation and chronic cerebrospinal venous insufficiency as one of the most common pathologies evaluated as part of neurodegenerative processes in the central nervous system..." http://www.ncbi.nlm.nih.gov/pubmed/24053081