Viual lo in children with neurofibromatoi type 1 and optic pathway glioma: Relation to tumor location by magnetic reonance imaging

PURPOE: To examine the potential for viual acuity lo, and it relation to extent and location of optic pathway glioma in a cohort of children with neurofibromatoi type 1 tudied with magnetic reonance imaging. METHOD: We reviewed the neuro-ophthalmologic record and brain/orbital magnetic reonance imaging can for 43 conecutive pediatric patient with neurofibromatoi type 1 and optic pathway glioma who were followed at the Children’ Hopital of Philadelphia. The preence of viual lo, defined a abnormal viual acuity for age in one or both eye, wa determined. Optic pathway glioma were claified by tumor extent and location according to involvement of the optic nerve, chiam, and potchiamal tructure by magnetic reonance imaging. REULT: Involvement of the optic tract and other potchiamal tructure at tumor diagnoi wa aociated with a ignificantly higher probability of viual acuity lo (P = .048, chi-quare tet). Viual lo wa noted in 20 of 43 patient (47%) at a median age of 4 year; however, three patient developed viual acuity lo for the firt time during adolecence. CONCLUION: In pediatric patient with neurofibromatoi type 1 and optic pathway glioma, the likelihood of viual lo i dependent on the extent and location of the tumor by magnetic reonance imaging and i particularly aociated with involvement of potchiamal tructure. Furthermore, older age during childhood (adolecence) doe not preclude the occurrence of viual lo. Cloe follow-up beyond the early childhood year, particularly for thoe with potchiamal tumor, i recommended.