Anatomoclinical Aspects of Dural Arteriovenous Shunts in Children

We review 29 children (presenting between 1985-1996) with dural arteriovenous shunts. By analysing the anatomical features from axial and angiographic imaging and examining the clinical history and pathophysiological characteristics, we hypothesize that different diseases can be distinguished and divided into three groups: dural sinus malformation (DSM), infantile type of dural arteriovenous shunts (IDAVS) and adult type of dural arteriovenous shunts (ADAVS). It was helpful to classify these diseases when assessing the treatment options and long-term prognosis. Our group of 29 children comprised 19 DSM, 7 IDAVS, 3 ADAVS. A slight male preponderance was noted in the DSM group. The range of symptoms encountered included mild cardiac failure and coagulopathies, macrocrania, developmental delay, mental retardation, seizures and focal neurological deficits (in the neonates and early infancy age group) with or without haemorrhagic venous infarctions secondary to venous outlet restriction. We found all types of lesion in the neonatal age group, but in general the different types of lesion correspond to the paediatric subgroups with DSM occurring in the neonatal age group, IDAVS in infancy and ADAVS in children. DSMs are revealed in the first few months of live and the prognosis is good if the torcular is not involved. Two types can be seen: 1) DSM involving the posterior sinus with or without the confluens sinusum, with giant dural lakes and slow flow mural AV shunting. Spontaneous thrombosis may further restrict cerebral venous drainage and subsequently lead to intraparenchymatous haemorrhagic infarction. 2) DSM involving the jugular bulb with otherwise normal sinuses but associated with a high flow sigmoi'd sinus AVF. The prognosis is excellent with embolisation treament. IDAVS are high flow and low pressure. The sinuses are large and patent with no lakes. Clinical onset is seen in the first few years of life and the shunts are initially well tolerated. Progressive symptoms (symptoms of raised ICP and venous ischaemia) develop at a later age and initially respond to partial embolisation. The long term prognosis is poor with neurological deterioration in early adulthood. ADAVS present in all age groups and almost all of them are located in the cavernous venous plexus. Post embolisation outcome is excellent.