Giant cystic arachnoid granulations: A rare cause of lytic skull lesions

Cranial Venous Outflow Obstruction and Pseudotumor Cerebri Syndrome

“…Ninety-five percent were located in the transverse sinuspredominantly the left. In Rosenberg et al's [145] report of 4 cases of giant arachnoid granulations presenting as osteolytic skull lesions, histological examination demonstrated loss of the normal stromal organisation. Instead large CSF filled cystic spaces were seen.…”

“…In 11 (50%) there were either bilateral venous sinus obstructions (7 cases) or a unilateral venous sinus obstruction in a dominant venous si- 145 Venous Obstruction and Pseudotumor Cerebri Syndrome nus (4 cases). These obstructions were all associated with pressure gradients across the point of stenosis.…”

Brain Herniations into the Dural Venous Sinuses or Calvarium: MRI of a Recently Recognized Entity

“…In their patients there were numerous blood vessels within the granulations. Arachnoid granulations may enlarge with age or in response to increased CSF pressure 1,7,8 . When arachnoid granulations are sufficiently large enough to fill the lumen of a DVS caus- ing local dilation and filling defects they are called "giant" 1,9 .…”

A Quantitative Method for Estimation of Volume Changes in Arachnoid Foveae with Age

“…1), are pits or depressions found on the endocranial surface. They are concentrated along the anterior two thirds of the sagittal edge of the parietal bones, and midline along the coronal suture on the posterior aspect of the frontal bone (1,2). They may be occasionally found along the transverse sinus (3).…”

“…They may be occasionally found along the transverse sinus (3). They are typically located parasagittally within 3 cm from the midline of the skull (1,2). Arachnoid foveae are closely associated with arachnoid granulations, which are projections of the arachnoid mater into the dural venous sinuses.…”