Single burr hole rigid endoscopic third ventriculostomy and endoscopic tumor biopsy: what is the safe displacement range for the foramen of Monro?

Objective: To investigate the safe displacement range of the foramen of Monro (FM) during single burr hole rigid endoscopic third ventriculostomy (ETV) and endoscopic tumor biopsy (ETB).

Methods: Eleven patients who received ETV/ETB for third ventricular and pineal region tumor were reviewed. The burr-hole location, the size, and the virtual displacement of FM were measured using neuronavigation software.