Anatomic variations of internal jugular vein, inferior petrosal sinus and its confluence pattern: Implications in inferior petrosal sinus catheterization.

OBJECTIVE: The purpose of this study is to describe anatomic variations of the internal jugular vein (IJV), inferior petrosal sinus (IPS) and their confluence pattern and implications in IPS catheterization. The anatomic route of IPS after going out of the cranium and its confluence patterns with IJV and will supply knowledge about typing of IPS-IJV junction.
METHOD: A review of the literature was performed.
RESULTS: There might be different routes for entering the intracranial segment of the IPS and multislice spiral computed tomography (MSCT) is effective in identifying the confluences of the IPS with the IJV and their courses. It is important to find the confluence of IPS with IJV for diagnosis and treatment of intracranial lesions via venous route. Meanwhile, IPS diameter at the confluence can significantly affect success of catheterization.
CONCLUSION: The classification and the theory of the development of the caudal end of the IPS may be useful in establishing treatment strategies that involve endovascular manipulation via the IPS.