Susceptibility Weighted Imaging: A Novel Method to Determine the Etiology of Aqueduct Stenosis

Abstract

The stenosis of aqueduct of Sylvius (AS) is a very common cause of obstruction to cerebrospinal fluid. Multiple etiologies are proposed for this condition. Because treatment is specific for correctable disorder, assessment of etiology gains importance. A case of pediatric hydrocephalus was diagnosed with stenosis of AS on magnetic resonance imaging (MRI). Susceptibility-weighted imaging (SWI) demonstrated blooming in the distal aqueduct and lateral ventricle, which was not seen on routine MRI sequences. The findings suggest that old hemorrhage is a cause of chemical arachnoiditis and adhesions causing aqueduct stenosis and hydrocephalus. To our knowledge literature is very scarce, wherein SWI is being used to confirm blood products as a cause of aqueduct stenosis; hence SWI should be routine protocol in imaging of pediatric hydrocephalus. Etiology, clinical presentation, role of imaging, and, in particular, SWI in evaluation of aqueductal stenosis is discussed.

Keywords

susceptibility weighted imaging - aqueductal stenosis - magnetic resonance imaging - hydrocephalus

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