Anatomical Evaluation Of The Venous Sinuses In The Region Of The Confluence Of Sinuses Using Digital Subtraction Angiography

Objective: The aims of this study were to evaluate anatomy of theconfluence of sinuses and to assess their clinical significance using digitalsubtraction angiography(DSA).Method: The confluence of sinuses and its relevant venous sinuses wereanalyzed using bilateral carotid and vertebral artery angiography in203adultsfrom June2011to January2012at the first afflicated hospital of GuangxiMedical University. We evaluated the anatomy of the sinuses near theconfluence include the method of drainage of the superior sagital sinus(SSS)into the transverse sinus(TS), the drainage of the straight sinus(SS) into the TS,the drainage type of the bilateral TS, comparison of size between the bilateralTS, the communication type of the bilateral TS and the frequency of persistenceof the occipital sinus(OS).Results: The drainage pattern of the SSS into the TS was classified intofour types. Sc type: The SSS reached the centrally located confluence and then divided into the bilateral TS (30.0%); Sd type: The SSS became prematurelyduplicated into the right and left limbs, draining into the same side TS (26.7%);Sr type: The SSS drained predominantly into the right TS, with its posteriorportion deviating to the right side(44.2%); and Sl type: The SSS drainedpredominantly into the left TS, with deviation to the left side at its posteriorportion(9.2%). The drainage pattern of the SS into the TS was classified intothree types. Rc type: The SS reached the centrally located confluence and thendivided into the bilateral TS (68.0%); Rr type: The SS drained predominantlyinto the right TS(18.2%); and Rl type: The SS drained predominantly into theleft TS(13.8%). The drainage type of the bilateral TS was classified into fivetypes: Equal drainage（36.4%）; Drainage mainly from the right side（48.8%）;Drainage mainly from the left side（5.9%）; Drainage limited to the right side（6.9%）Drainage limited to the left side（2.0%）. Comparison in size betweenthe bilateral TS: The bilateral TS were almost equal in size (21.7%); Right TSmildly stenosi（s3.9%）;Right TS seriously stenosi（s0.5%）; Right TS completelyaplastic（2.0%）; Left TS mildly stenosis（35.5%）; Left TS seriously stenosis（10.8%）; Left TS completely aplastic（3.0%）. The communication type of thebilateral TS: direct communication（49.8%）; indirect communication（50.2%）.Occipital sinus: Persistent OS were recognized5.9%in our study by carotidangiography.Conclusion: DSA is a accurate and reliable method to evaluate theconfluence and its relevant venous sinuses. It can provide useful information for the diagnosis and differential diagnosis of cerebral venous disease and certainsurgical intervention.