Craniotomy Procedure Step by Step: Which Equipment Is Used

Craniotomy: what is it and what types exist?

In a craniotomy a bone flap is cut, lifted and later fixed back in place. This differs from a craniectomy, where the bone is not replaced, and from a simple burr hole used for drainage or monitor placement. Craniotomy types are usually named after the approach: frontal, temporal, pterional, parietal, occipital, suboccipital and others, each defined by the location of the flap.

A fuller comparison is in craniotomy, craniectomy and burr hole compared. A special variant, performed with the patient awake for mapping of function, is discussed in awake craniotomy set-up.

Step 1 and 2: positioning and head fixation

After anaesthesia the patient is positioned according to the approach, and the head is fixed in a skull clamp or placed on a non-invasive headrest. The clamp holds the head rigid for the whole operation and gives a base for navigation tracking and retractor arms. The DORO Multi-Purpose clamp, for example, covers newborns to seniors and allows invasive, non-invasive or combined fixation; see DORO Multi-Purpose.

The table, the headrest and the clamp must be compatible, and any intraoperative imaging plan decides whether radiolucent components are needed. Registration for neuronavigation, if used, is done after fixation, so a clamp that moves would invalidate it.

Steps 3 and 4: incision, burr holes and craniotome cuts

The skin is prepared and incised, soft tissues are reflected, and the bone is exposed. Burr holes are made with a cranial perforator; the NOUVAG Cranial Perforator runs at 80 to 1,200 rpm with 120 Ncm peak torque and uses single-use perforator bits. The dura is separated from the underside of the bone, then the bone flap is cut with a craniotome.

The NOUVAG Craniotome operates at 1,000 to 60,000 rpm with a dura protector and turned or diamond milling tools. Together with a motor system, a foot switch and irrigation, these tools form the powered part of a craniotomy drill set. Some teams use a bone saw or Gigli for parts of the cut, depending on their technique.

• Cranial perforator for burr holes
• Craniotome with dura protector for the bone flap
• Irrigation and suction to cool the bone and clear debris
• Bone wax, haemostats and bipolar for bleeding control

Steps 5 and 6: intradural work and closure

The bone flap is removed, the dura is opened and the surgeon works under a microscope or exoscope with microinstruments, retractors and suction. In a craniotomy for tumor resection, navigation, neurophysiological monitoring and sometimes intraoperative imaging support the resection. Brain retraction systems attach to the clamp rail and hold blades without a person holding them.

At the end the dura is closed, the bone flap is replaced and fixed with plates or other fixation, and the scalp is closed. How long surgery takes varies widely with the indication and complexity, so planning of the OR schedule and staffing is done by the surgical team.

Planning the OR and sourcing the equipment

To prepare, list the table and head fixation, motor and handpieces, instrument sets, microscope, navigation and monitoring. Our checklist in neurosurgery equipment list helps structure the plan.

Beckfinity supplies head fixation from Black Forest Medical and motor systems and handpieces from NOUVAG to UAE hospitals. To discuss your craniotomy set-up, contact our specialists.