The basics of intraoperative diagnosis in neuropathology.

Intraoperative pathologic consultation continues to be an essential tool during neurosurgical procedures, helping to ensure adequacy of material for achieving a pathologic diagnosis and to guide surgeons. For pathologists, successful consultation with central nervous system lesions involves not only a basic familiarity with the pathologic features of such lesions but also an understanding of their clinical and radiologic context. This review discusses a basic approach to intraoperative diagnosis for practicing pathologists, including preparation for, performance of, and interpretation of an intraoperative neuropathologic evaluation. The cytologic and frozen section features of select examples of common pathologic entities are described.