Hydatid Disease of the Central Nervous System Imaging Characteristics and General Features

Background;Hydatiddiseaseprimarilyaffects the liverand typicallydemonstratescharacteristic imaging findings. Secondary involvement due to hematogenous disseminationmay beseeninalmostanylocations,e.g., lung,kidney,spleen,boneandcentralnervoussystem (CNS). Objectives:ToreviewthedifferentaspectsofhydatidosisoftheCNSbrieflyanddiscussthe pathognomonic features and rare varieties of radiological findings useful in preoperative diagnosisofthediseaseinthehumanCNS. Material& Method; Ina retrospectivestudy,therecordsofalmost100casesofCNShydatidosis wereanalyzed.Theavailableimageswerereviewedbyindependentobservers,either a radiologistora neurosurgeon,andreportedseparately. Results; In skull X-ray films, nonspecific changes denoted increased intracranial pressure, skull asymmetryandcurvilinear calcification in rare instances.Computed tomography (CT) andmagneticresonanceimaging(MRI)demonstratedtheroundoroval,well-definedcystic masswithan attenuation or signal intensitysimilar to that of cerebrospinal fluid,withno associatedperifocaledema,andnocontrastenhancementasthepathognomonicfindingsof brainhydatidosis.Similar findingsweredetectedinhydatidcystsinvolvingtheorbit,spinal column and spinal cord with some variations. Such findings asmild perifocaledema,nonhomogenous contrast enhancement, non-uniform shapes, calcification and multiplicity or septationshavebeentheatypicalradiologicalfindings. Conclusion;Inendemicareas,familiaritywithtypicalandatypicalradiologicalmanifestations of hydatid disease of theCNS, will be helpful inmaking prompt and correct preoperative diagnosisleadingtoa bettersurgicaloutcome.