Cerebrum functional network alterations following posterior fossa surgery in Children

Pediatric posterior fossa lesions are frequent, and surgery in this area often results in cerebellar injury. Despite improved surgical methods, the impact on brain functional networks and their role in motor and cognitive performance remain unclear. Existing research mainly involves adults or children who received additional therapies, obscuring the effects of isolated cerebellar damage. Evidence from pediatric functional neuroimaging after posterior fossa surgery is limited.

In this cross-sectional study, we examined 12 postoperative children and 13 healthy peers using resting-state functional magnetic resonance imaging (rs-fMRI) and the CNS Vital Signs (CNS VS) computerized neurocognitive battery. The CNS VS battery provided age-adjusted standard scores across multiple cognitive domains as well as motor speed (MotSpd) and psychomotor speed (PsyMotSpd) indices.

Short-term postoperative results indicated that most cognitive domains assessed by CNS VS did not differ significantly between groups, whereas the patient group showed lower scores on MotSpd, PsyMotSpd, and the neurocognitive index (NCI). Brain imaging analyses revealed increased regional activity and altered seed-based functional connectivity in several cortical regions of the patient group relative to controls. Exploratory correlation analyses conducted across all participants showed that several of these imaging metrics were negatively associated with motor-related scores; however, one functional connectivity measure was positively associated with MotSpd.

These findings suggest that children following posterior fossa surgery exhibit measurable alterations in supratentorial brain network organization alongside relatively preserved cognitive performance but reduced motor-related scores on the CNS VS battery. The negative associations between certain imaging metrics and motor performance may reflect heterogeneous or inefficient network reorganization rather than a straightforward compensatory process. Further longitudinal and interventional studies are needed to clarify the functional significance of these network changes and to inform rehabilitation strategies.