Abstract
Screening studies have shown detection of optic pathway gliomas (OPGs) in 8 to 31%
of children with neurofibromatosis type 1 (NF1). Many of those affected show prolonged
indolent phases, but others develop vision disturbances even before diagnosis and
treatment. We assessed the clinical presentation at diagnosis, location, natural progression,
and risk factors for impaired vision of OPG. The clinical database of the NF1 multidisciplinary
clinic of Schneider Children's Medical Center of Israel was reviewed for all patients
diagnosed and followed with NF1 during 2007 to 2019. OPG was diagnosed by hyperintensity
and thickening along the optic pathway on T2-weighted brain magnetic resonance imaging
(MRI), with or without contrast enhancement. Of 257 children with NF1 who underwent
MRI, 57 (22%) were diagnosed with OPG; 31 (54%) were females. Twenty-five (44%) had
familial NF1. Fifteen (26%) who exhibited tumor progression and worsening in ophthalmic
examinations required treatment. Post-chiasmatic glioma was a predictive factor for
treatment (p < 0.05), whereas MRI done later and female gender were not significant. Four patients
who eventually needed therapy had normal ophthalmic examinations at least 1 year prior
to their first MRI. For 6 (40%) of the patients treated, vision continued to worsen.
Our findings demonstrate that normal ophthalmic examinations do not always exclude
OPG in children with NF1. Early brain MRI before age 36 months may detect OPG, lead
to better follow-up and early treatment, and help improve vision outcome.
Keywords optic pathway gliomas - neurofibromatosis type 1 - brain MRI