Supplementary Material for: Crouzon’s Syndrome With A Dominant Sinus Pericranii Draining Transverse Sinus- Report Of A Rare Association And Review Of Literature.

Introduction - Crouzon’s syndrome and sinus pericranii are rare entities. Only few cases having both the features are reported. Sinus pericranii most commonly drain in relation to superior sagittal sinus and their communication to major posterior dural sinuses is rare. Case Report - We report a rare case of Crouzon’s syndrome with sinus pericranii at a sub-occipital location with termination of left transverse sinus into the sinus pericranii draining further through the extracranial suboccipital and extravertebral cervical venous plexi into external jugular veins. Distal transverse sinus and sigmoid sinus on left side were absent. Discussion/Conclusion - Crouzon’s syndrome with sinus pericranii is an extremely rare entity. Sinus pericranii with communication to major posterior dural venous sinuses are also rare and mostly associated with multi-suture craniosynostosis. Management depends on the volume of venous blood they are draining. Most of them are dominant type and their occlusion is not feasible. Preoperative diagnosis of a dominant sinus pericranii is essential for proper surgical planning as it needs to be preserved mandatorily to prevent cerebral venous infarction.