Developmental venous anomaly causing trigeminal neuralgia.

Department of Surgical Specialties, Division of Neurosurgery, Pedro Ernesto University Hospital, State University of Rio de Janeiro, Rio de Janeiro RJ, Brazil; Department of Neurology, University of São Paulo, São Paulo SP, Brazil. Trigeminal neuralgia (TN) is a syndrome characterized by paroxysms of facial pain affecting mainly middle and oldaged patients. Although TN’s pathogenesis is not fully understood, there is increasing evidence that TN is caused by demyelination of trigeminal sensory fibres mostly owing to an arterial neurovascular compression on the root entry zone (REZ) of the trigeminal nerve. Veins, on the other hand, can be regarded as the only offending vessel in up to 13% of the patients. Other unusual causes of TN include intrinsic brainstem lesions or even compression of the trigeminal nerve root by tumors, in which the compression can occur by the tumor itself, by an interposed blood vessel or by a distortion of the posterior fossa contents displacing the nerve root towards blood vessels or the skull base. Nonetheless, in a small number of patients, the pathogenesis remains to be determined. Although vein compression is usually accepted in TN’s pathogenesis, either alone or in combination to arterial compression, developmental venous anomaly (DVA) causing TN is seldom reported with 17 cases described to date. A patient with a classical longstanding right frontal division TN caused by a DVA is reported emphasizing the clinical features and management of such condition.