Acquired nystagmus as the initial presenting sign of chiasmal glioma in young children.

Abstract

The aim of the study was to investigate the incidence of nystagmus at diagnosis in children with optic pathway glioma involving the chiasm and hypothalamus. Twenty-two patients with a measurable optic pathway/hypothalamic glioma (without neurofibromatosis-1) were followed in our center from 2001 to 2013. The medical files were retrospectively reviewed for demographic and clinical findings, and the imaging scans, for tumor characteristics. There were 9 boys and 13 girls of mean age 3.5±4.4years at diagnosis; 15 were aged <2 years. Tumor size ranged from 10×6mm to 62×29mm. Mean duration of follow-up was 8.3±5.4 years. Nystagmus was detected at diagnosis in 10 children (45%), all <2 years old (66.6% of the younger group); no child older than 2 years presented with nystagmus. Nystagmus, once present, did not resolve and continued throughout follow-up. There were no cases of new onset of nystagmus during follow-up in the children in whom it was not detected at diagnosis. Treatment consisted of partial resection/biopsy with/without shunting (n=13) and chemotherapy (n=19) with (n=2) or without adjuvant radiation. Of the 22 children, 6 had a radiographic response to treatment, 8 remained stable, and 8 (all of whom received chemotherapy) showed disease progression despite treatment. In conclusion, monocular nystagmus is a more common presenting sign of optic pathway/hypothalamic glioma in children <2 years old than previously estimated. Although subtle, nystagmus has a very narrow differential diagnosis, and its presence should raise suspicions of a chiasmal tumor with prompt referral for imaging. The visual prognosis is moderate to poor.