Optic pathway glioma: long-term visual outcome in children without neurofibromatosis type-1

Little is known about the visual outcome of children affected by an optic pathway glioma (OPG).

We evaluated the long-term visual outcome of 32 consecutive children affected by OPG without neurofibromatosis type-1 referred to the Pediatric Department of Padua University and managed according to standardized strategies.

Eight children received chemotherapy, 10 radiotherapy, 7 both chemotherapy and radiotherapy, whereas 7 were untreated. At presentation, visual acuity (VA) was normal in 22 children (13 unilaterally and 9 bilaterally), and reduced in 10. At follow-up, VA had improved in 6 patients; it was stable in 8 and worse in 18. Visual field, assessed in 29 children, was normal in 9 and reduced in 20. The number of children with some grade of visual impairment increased from 7 to 10 during follow-up. Of the 17 children in whom the tumor became significantly smaller, VA improved in 6, was stable in 3, and worse in 8. Of the 6 children with improved VA, 5 received radiotherapy, and their papilla was normal or mildly pale. After a median follow-up of 6 years, 26 patients are alive with stable disease.

The visual prognosis of children with OPG is unsatisfactory. Older children treated with radiotherapy seem to have a better visual outcome than younger children. Severe optic pallor at diagnosis or during follow-up may be indicative of a negative prognosis.