Safe handling of veins in the pineal region-a mixed method study.

Surgical experience in pineal surgery is largely confined to a few experienced surgeons and may be lost when they stop their practice. The objective of this study is to systematically preserve and analyze valuable practical knowledge of pineal region surgical venous anatomy. A survey was constructed to obtain experienced surgeons' perception of estimated risks and individual experience following occlusion of veins during pineal surgery. Data were qualitative and analyzed with a mixed methods approach. Of the 126 invited neurosurgeons, 40 submitted completed questionnaires. General agreement existed of which veins were associated with high and low risks following occlusion. The risk of death was estimated to be high with sacrifice of the vein of Galen (83%), both internal cerebral veins (69%) and the basal veins (58%). The risk of death was estimated to be lower with the sacrifice of both superior vermian veins (13%) and one internal occipital vein (10%). Importantly, a sub-group of experienced surgeons reported substantial risk of death and consequences with the sacrifice of cerebellar bridging veins (8-13%). Our findings provide a coherent picture of surgical risk with venous sacrifice, which can inform the surgical community of systematically gathered views from aggregated surgeries of a very large cohort of patients. Extensive presurgical radiological workup and anatomical studies seemed to correlate more cautious risk estimations. Our findings increase available knowledge of risks of venous complications.