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Updated: Jan 22, 2026

A Bedside, Single Burr Hole Approach to Multimodality Monitoring in Severe Brain Injury
Published on: March 26, 2019
Surgical Rescue Technique for Incomplete Burr Hole Using a Small Bone Piece and the Craniotome
Toru Yoshiura1, Kojiro Wada1, Kosuke Kumagai1
1Department of Neurosurgery, National Defense Medical College, Saitama, Japan.
Background:
Incomplete penetration of a burr hole sometimes occurs when performing a craniotomy in elderly patients due to osteoporosis. Completion of the burr hole takes more time and may sometimes cause tearing of the dura mater. We have introduced a small bone piece method that can easily and reliably recover an incomplete burr hole safely.
Methods:
1) Cut out a small bone piece of the outer table of about 5-mm size using a rongeur. 2) Place the small bone piece in the center of the incomplete burr hole. 3) Push on the small bone piece with a craniotome after unlocking the safety stop mechanism. 4) Restart and complete the burr hole with the craniotome.
Results:
We succeeded in 10 of 11 incomplete burr holes. One case that failed had osteoporosis. There were no complications.
Conclusions:
Application of the unlocked craniotome on the small bone piece can easily complete the burr hole. Less bone deficit is caused compared with making a new burr hole. In addition, time is saved without changing the attachment, and the burr hole is completed safely. This small bone piece method is effective to recover an incomplete burr hole.
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