The Keyhole Concept in Neurosurgery

In all cases, meticulous preoperative planning was done for determining the site, size, and optimal placement of the craniotomy as well as the trajectory toward the surgical target. Most importantly, the surgical approach was performed either completely or at least under permanent presence of the responsible senior surgeon from the moment of patient positioning until wound closure. The minimally invasive keyhole approaches allowed safe intraoperative control and adequate dealing with intracranial lesions. Essential preconditions for keyhole surgery were 1) careful selection of cases, 2) accurate preoperative planning, 3) placement of the craniotomy tailored to the individual case, and 4) intraoperative use of transcranial endoscope-assisted microsurgery techniques. Advantages of intraoperative endoscopic visualization were increased light intensity, extended viewing angle, and clear depiction of details even in hidden parts of the surgical field.