The Straight Sinus in the Human Cerebral Venous System: An Anatomical Evaluation Using Magnetic Resonance Venography

Aim: In our study, we aimed to evaluate the anatomical variations of the straight sinus, its angulations and its constituent structures by magnetic resonance venography (MRV). Methods: In this retrospective study, MRV data of patients admitted to our hospital with various complications were evaluated. The ages of the patients ranged from 10 to 73 years and the types of termination of the straight sinus in the confluence of sinuses and the contributions of the inferior sagittal sinus and great cerbral vein to the straight sinus were analyzed in 200 patients, 111 females and 89 males. Results: When the termination types of the cases were analyzed, 34% of the patients had complete intersection (type I), 55% had partial intersection (type II) and 11% had non-intersecting variation (type III). The inferior sagittal sinus, which participates in the formation of the straight sinus, was aplasic in 53 patients (26.5%) and hypoplasic in 67 patients (33.5%). It was clearly visualized in the remaining 80 patients (40%). The great cerbral vein was present in all cases and participated in the formation of the straight sinus. Conclusion: The morphologic structures of the dural venous sinuses may differ not only between individuals but even between the two cerebral hemispheres of the same person, depending on embryologic development. A thorough knowledge of these anatomical variations provides guidance to surgeons, particularly during posterior cranial fossa operations, and contributes to the prevention of possible complications.