Surgery of Pineal and Pineal Region Tumours: The Sub-Occipital Transtentorial Approach for Pineal Tumours: How We Do It in Lyon.

The sub-occipital transtentorial approach for pineal and pineal region tumours is reported as realized in Lyon. The approach described by C. Lapras is still performed today with a large skin flap and a large bone flap, which is sawn flush with the superior longitudinal sinus and the transverse sinus.The large bone flap allows elevation and separation of the hemisphere, avoiding its compression against the internal edge of the parietal bone.Opening the tentorium allows broad visualization of the pineal region space and of the venous arch formed by the basilar veins and the Galen vein.Protecting the occipital lobe with a rubber blade and cottonoids prevents compression of the calcarine scissure and has helped to reduce the incidence of the homonymous lateral hemianopia, which was the main criticism of this approach. In recent years, endoscopy assistance at the end of surgery has helped increase the rate of complete tumour removal by detecting pieces of tumour that were left in place.In Lyon, it was realized in more than 300 procedures.