The effect of cerebellar tumor resection on pain perception in pediatric patients.

Abstract

126 Background: Acute cerebellar infarctions have been shown to lead to affective and cognitive deficits in pediatric patients. However, the consequences of cerebellar insult on pain processing are unknown. Recent evidence not only suggests that the cerebellum plays a role in affective processing, but it also demonstrates increased activity in this area when individuals experience experimental or clinical pain, particularly in the posterior cerebellum. The goal of this study is to evaluate the effect of cerebellar resection of low-grade astrocytomas in children on pain perception. Describing the impact of this treatment may be of particular importance in children, as it may alter sensory development into adulthood. Methods: Twelve pediatric patients treated with surgery only for non-malignant astrocytomas (mean age = 13.78 ± 5.64) and ten age-, gender-, race- and handedness-matched healthy controls (mean age = 14.52 ± 5.96) were evaluated using quantitative sensory testing and magnetic resonance imaging, comprising diffusion tensor imaging, resting state and event-related functional MRI scans. Five of these patients had tumors localized to the posterior cerebellar hemispheres. The psychophysical measures assessed included heat and cold detection thresholds (HDT, CDT), heat and cold pain thresholds (HPT, CPT), and cold pain tolerance using a cold pressor task. Results: Patients with lesions in the posterior cerebellum (n = 5) were shown to have a significantly lower tolerance to the cold pressor test than controls (n = 10). No significant differences were detected for the threshold measures. This suggests increased pain sensitivity in these patients to suprathreshold noxious stimuli compared to controls. Patients with lesions that did not include the posterior cerebellar hemispheres (n = 7) did not show significant differences with controls in terms of cold pain tolerance or thresholds. Conclusions: The differences in cold pain tolerance between patients and controls are presumed to result from damage to the posterior cerebellar hemispheres, potentially interfering with the modulation of pain pathways. Analysis of the preliminary imaging data is underway and recruitment is ongoing. Support: NIH/R21CA185870(EM)