The moment that determines operative outcome in neurosurgery is not the moment the clip is applied — it is the moment before the retractor is placed, when the anatomy either exists clearly in the surgeon's mind or does not. When that map is incomplete, the consequences are not missed laboratory values or adjusted doses — they are avulsed lenticulostriate arteries, sacrificed anterior choroidal arteries, and permanent deficits that no postoperative intervention will reverse. This book builds the three-dimensional spatial framework that converts anatomical knowledge into operative fluency — corridor by corridor, danger relationship by danger relationship, across the full neuroaxis. • The Surgical Corridor System — a five-point operative framework applied to every major approach in the book, from the transsphenoidal corridor to the far-lateral, so the anatomy is organized the way surgery actually unfolds • Perforator anatomy at operative resolution — the thalamoperforators, the anterior choroidal artery, and the lenticulostriates mapped as surgical danger relationships, not labeled diagrams • Brainstem safe entry zones — all seven zones defined by the functional structures on each side, with lesion-adapted entry point selection for brainstem cavernous malformations • The deep venous system as operative boundary — internal cerebral veins, vein of Galen, and the straight sinus developed as the inviolable limits they are in transcallosal and posterior interhemispheric surgery • DBS target anatomy at submillimeter resolution — STN, GPi, and VIM with MER signatures, stimulation-defined therapeutic windows, and the anatomical basis of every side effect • Sixty ABNS-format examination items — spanning every corridor, consolidated in the Surgical Corridor Master Compendium Written for neurosurgery residents preparing for the ABNS Neuroanatomy Examination, fellows reviewing subspecialty corridor anatomy, and attending surgeons who want a corridor-organized reference before complex cases. If the anatomy should never be the limiting factor in your operating room, this is where that standard begins.
