Professor Hopf is currently director of the NeuroChirurgicum Stuttgart, a center for endoscopic & minmal invasive Neurosurgery. He is a world-recognized expert in Neuroendoscopy, minimally invasive and keyhole surgical approaches for a broad spectrum of brain tumors, skull base tumors as well as vascular malformations and has considerably contributed to the development of Endoscope-assisted Microsurgery (EAM) and Endoscopic Skull Base Surgery. He is also specialized in extended endoscopic transsphenoidal surgery for tumors of the sellar region, lesions of the brainstem and medulla, as well as tumors of the pineal region.