Intraventricular arachnoid cyst in the adult

Introduction. Intracranial arachnoid cysts are benign, congential cystic lesions found in infancy. The commonest sites are the lateral fissure and the posterior fossa. Exceptionally they may be found in the ventricular system. Clinical case. We describe a 69 year old patient with a clinical history of headache and tingling of the face for 24 hours. Diagnosis of a lateral ventricle arachnoid cyst was made on computerized tomography and magnetic resonance. Treatment was surgical with excision of the wall of the cyst and the communication with the ventricle. Conclusion. We review 14 cases previously described (9 adults and 5 children), analyzing their clinical and radiological features, type of treatment given and the different theories proposed as to pathogenesis.