The clinical presentation of children with tumours affecting the anterior visual pathways.
To review the ways in which children with tumours affecting the anterior visual pathways present and to determine the extent of visual loss at presentation and the visual prognosis after treatment. A retrospective review of the 17 children (age 1-13 years at presentation) referred to a specialist paediatric oncology unit. Ten children had extrinsic tumours affecting the chiasmal area whilst 7 had intrinsic gliomas affecting the optic nerve and/or chiasm. Patients were followed up for up to 13 years (median 2 years). The children studied presented with a variety of symptoms including headaches, lethargy and growth failure. Despite the clinical finding of marked visual loss in several cases, visual failure was not prominent amongst the presenting symptoms. After surgical intervention and other treatment vision stabilised or improved; eyes with no perception of light for short periods could regain substantial vision. Children with progressive visual deterioration due to tumours do not readily verbalise their difficulty and may have profound loss at presentation. Standard clinical tests of vision will identify the extent of damage. Visual prognosis depends on the underlying pathology and length of history but prompt treatment may lead to substantial improvement in vision.