Visual field defects in children with brain tumors

Introduction: Visual field defects (VFDs) are detected in up to 25% of children with brain tumors and early identification of VFDs is crucial for timely treatment and vision preservation. This study investigated the frequency and associated factors of preoperative VFDs in pediatric brain tumor patients. Methods: Medical records from 485 children diagnosed with brain tumors in Denmark from 2007 to 2017 were reviewed. Data on demographics, tumor characteristics, and clinical findings, including general and ophthalmic symptoms were collected. Results: Of 485 patients, 198 (41%) underwent visual field testing prior to surgery; 51 (26%) had VFDs. Children with VFDs experienced poor vision to a higher extent than children with normal visual fields (39% vs. 15%, p <.001). Reduced best-corrected visual acuity (BCVA) (53% vs. 27%, p <.001), abnormal pupillary responses (27% vs. 8.8%, p <.001), retinal abnormalities (1.4 vs. 7.8, p =.039), and papilledema (31% vs. 13%, p =.003) were also more common in the children with VFDs. However, 25% of children with VFDs reported no visual symptoms, and 12% showed no other abnormalities on ophthalmic examination aside from the VFDs. Children who were not examined were younger (5.8 vs. 9.6 years, p <.001) and had a higher mortality rate (23% vs. 15%, p =.018). Conclusion: VFDs are common in children with brain tumors but may go undetected due lack of symptoms, findings, unreliable testing methods, or poor general health. Visual field testing is important for diagnostic purposes and should be considered in all children, particularly those presenting with poor vision, abnormal pupillary responses, or signs of papilledema.