Abstract
Abstract: :
Purpose: To investigate the value of total-field and hemifield VEPs in pediatric and juvenile patients affected by intra-cranial chiasmatic tumors. Methods: 21 subject, 10 females and 11 males, affected by chiasmatic tumors. 25 age-matched normal subjects total-field and hemifield VEPs were recorded using two temporal frequencies for transient (1,9 Hz) and for steady-state (8.33 Hz).We measured the P100 implicit time and the N75-P100 amplitude in the transient and the second harmonic after Fourier transform in the steady-state VEPs. Results: Pattern VEP implicit times were significantly delayed in patients with intracranial tumors (p<0,001). Patients with visual field defects presented, on average, delayed implicit times compared to control group and to patients without visual field defects. Considering the pattern VEPs amplitudes, the patients with visual field defects presented significant lower amplitudes than the other two groups. Conclusion: Our study confirmed the suitability of the pattern sector VEPs to estimate patients with perimetric defects.
Keywords: 356 clinical (human) or epidemiologic studies: systems/equipment/techniques • 393 electrophysiology: clinical