Imaging diagnosis of arachnoid cysts

Arachnoid cysts are malformed lesions that contain a fluid similar to the cerebrospinal fluid, and are usually located within the arachnoidal membrane. They represent 1% of all intracranial lesions, and in recent years, with the development of radiological techniques, the clinical detectability of arachnoid cysts seems to have increased. Although the majority of diagnosed arachnoid cysts are located in the cranial cavity and especially in the Sylvian fissure, a small number are located at spinal level and they can occur extra- or intra-spinally. An analysis is carried out, detailing the various tests used for the diagnosis of both intracranial and spinal arachnoids cysts, analysing the indications of each one depending on the location of the cysts and patient age. (C) 2015 Sociedad Espanola de Neurocirugia. Published by Elsevier Espana, S.L.U. All rights reserved.