MRI-compatible skull-base pin fixation for advanced image-guided pediatric neurosurgery using augmented reality in infants younger than one year: A feasibility study

Rigid cranial fixation in infants younger than 1 year is controversial because thin, incompletely ossified calvaria predispose to skull fractures, epidural hematomas, cerebrospinal fluid (CSF) leaks, and scalp injury. However, neuronavigation, augmented reality (AR), and intraoperative MRI (iMRI) require stable head immobilization.

Four infants aged 5, 4, 7, and 10 months underwent surgery for choroid plexus papilloma, pineal atypical teratoid rhabdoid tumor, hemimegalencephaly, and occipital focal cortical dysplasia, respectively. An MRI-compatible head holder served as both fixation device and iMRI coil (prone position n = 3, supine n = 1). Low-pressure skull-base pinning (below 45 N; both lateral sphenoid wings and upper mastoid) avoided thin calvarial regions. Neuronavigation, microscope-based AR, and iMRI were integrated in all cases.

Stable immobilization sufficient for neuronavigation (registration accuracy below 2 mm), AR-guided microsurgery, and repeated iMRI was achieved in all patients without loss of fixation. iMRI confirmed gross total resection in three cases and complete disconnection on diffusion tensor imaging after hemispherotomy. No fixation-related complications, new or unexpected neurological deficits, or wound-healing disorders occurred during a follow-up of 5-12 months (median 5.5 months).

In this small technical series, low-pressure skull-base pin fixation with an MRI-compatible head holder provided stable immobilization without fixation-related complications in infants undergoing advanced image-guided neurosurgery. These results demonstrate technical feasibility but do not establish safety, which requires larger studies. Careful skull-base pin placement may reduce classical pinning complications while enabling multimodal neurosurgical techniques in infants.