Intraoperative MRI Head Holder: What to Specify for an iMRI Suite

Why intraoperative MRI neurosurgery needs special fixation

In intraoperative MRI neurosurgery the patient is imaged during the operation so that the extent of a resection can be checked before closing, or navigation can be updated after brain shift. The head must therefore hold position through repeated movements between the OR and the magnet, or within a combined suite where the magnet moves to the patient.

Every component near the scanner must be suitable for the magnetic environment, which is a matter of the manufacturer's labelling (MR Safe, MR Conditional or MR Unsafe) and of the field strength and conditions in your suite. Never assume compatibility from appearance; ask for the MR labelling documentation.

MRI compatible skull clamp: what to look for

An MRI compatible skull clamp should be made without ferromagnetic parts in the imaging area, be labelled for the field strength and scanner type used, and cause limited image artefact so that the surgical site stays clear. Ask for the labelling statement, the maximum field strength it covers, and any restrictions on pin type.

The pins are part of the system. The DORO LUCENT range uses disposable skull pins that minimise artefacts. Confirm in the quotation which pin type is supplied and that it matches the labelling.

DORO LUCENT iMRI and iXI

The DORO LUCENT iMRI is used in head and neck surgery when rigid cranial fixation is combined with intraoperative MRI. A variant of the DORO Skull Clamp Radiolucent mounts to the OR table transfer board via a parallelogram adaptor, keeping the familiar 3-pin workflow. Versions are offered for MAQUET, TRUMPF and Mizuho tables and as a set for IMRIS suites. The DORO LUCENT Headplate allows the head to be positioned before pinning.

The DORO LUCENT iXI supports intraoperative MR, CT and angiography, so bone and soft tissue can be assessed in the same surgery. It pairs a parallelogram design with a classic 3-pin skull clamp, mounts directly to the transfer boards of Maquet OR tables and supports Brainlab Automatic Image Registration. The iMRI system is compatible with leading image-guided surgery systems, including Brainlab AIR depending on the IMRIS scanner used.

• Classic 3-pin workflow with parallelogram adaptor
• Versions for MAQUET, TRUMPF, Mizuho tables and IMRIS suites (iMRI)
• Transfer-board mounting for Maquet tables (iXI)
• Quick-Rail for retractors and accessories (iXI)

Coil integration, navigation and monitoring

The head fixation and the MR coil must be designed together. Check how the coil sits around the clamp, whether the scanner gantry or bore allows the head to enter with the fixation attached, and how cables and tubes are routed. A head holder that is ideal on the table but blocks the coil is of little use.

Monitoring equipment is part of the same question. For intracranial pressure monitor MRI safety, check the labelling of the catheter, cable and monitor individually rather than assuming one statement covers all. The same applies to anaesthesia equipment, infusion pumps and neuro-monitoring leads. For the CT counterpart see head fixation for intraoperative CT.

Planning checklist for project teams

Agree the scanner model and field strength, the OR table and transfer system, the navigation system and the radiolucent range you need. Request MR labelling documents, the instructions for use and cleaning procedure, and a plan for staff screening and training. A written site survey from the supplier is worth requesting. Compare the wider options in radiolucent headrest systems.

Beckfinity supplies the Black Forest Medical range and can coordinate with your project team. Request a quote for your iMRI suite.