Endoscopic Endonasal Transclival Approach to Pontine Cavernous Malformations in the Pediatric Population

Brainstem cavernous malformations (CMs) carry high hemorrhage risk and morbidity due to their eloquent location. Although modern microsurgical approaches emphasize safe entry zones, endoscopic endonasal transclival approaches (EETA) have emerged as a less invasive midline corridor for ventral pontine lesions, potentially reducing brainstem manipulation. However, pediatric experience remains limited. We evaluated the safety, feasibility, and early outcomes of EETA for pontine CMs in children and characterized anatomic and technical considerations unique to this population.

We performed a single-institution retrospective case series of 6 pediatric patients (ages 5 months-17 years) treated between 2011 and 2025. All presented with symptomatic hemorrhage and/or focal neurological deficits from ventral pontine CMs. Preoperative evaluation included MRI, computed tomography, and hydrocephalus assessment. Operative planning emphasized pediatric constraints, including limited nasal corridors and developing skull base anatomy, with multilayer reconstruction techniques to minimize cerebrospinal fluid (CSF) leak risk. Routine postoperative CSF diversion (lumbar drain or external ventricular drain) was used. Outcomes included extent of resection, complications, CSF leak, infection, neurological recovery, and swallow function.

Gross total resection was achieved in all patients. Five demonstrated neurological improvement, including recovery of cranial neuropathies and hemiparesis; one had persistent abducens palsy. One CSF leak occurred with meningitis and resolved after external ventricular drain placement and flap revision without sequelae. No other leaks were observed. Two patients required temporary gastrostomy tubes, but all regained swallowing function. There were no arterial injuries, new permanent deficits, or mortality. The youngest patient (5 months) demonstrated feasibility in infancy with appropriate planning and specialized instrumentation.

EETA is a safe and feasible corridor for selected pediatric ventral pontine CMs, with favorable early outcomes when tailored to pediatric anatomy and careful patient selection.