Burr Hole to emergently relieve the intracranial pressure should be done in the left temporal region if no localising sign is found, to evaluate and decompress the dominant hemisphere Choice of side for initial Burr Hole Sta with a temporal Burr hole on the side Ipsilateral to a blown pupil: This will be on the correct side in >85% of epidural hemorrhages and other extra - axial mass lesions If both pupils are dilated, used the side of the first dilating pupil (if known) If pupils are equal, or it is not known which side dilated first, place on side of obvious external trauma If no localisation clues, place hole on left side (to evaluate and decompress the dominant hemisphere) Ref: Ramamuhi and PN Tandon's Textbook of Neurosurgery 3rd edition Vol-1 Pgno :442