Longitudinal clinical characteristics of patients with neurofibromatosis type 1.

Purpose: This study reports on longitudinal clinical characteristics of patients with neurofibromatosis type 1 (NF1) treated at the Department of Ophthalmology of the Medical University of Vienna.

Methods: This retrospective study included children with a genetically proven diagnosis of NF1. Clinical characteristics and outcomes, including best-corrected visual acuity (BCVA), refractive error, ocular motility, specific ophthalmological findings (e.g., Lisch nodules), and the presence of cutaneous café au lait stains were evaluated. Optical coherence tomography (OCT) and magnetic resonance imaging (MRI) were obtained to evaluate optic nerve abnormalities and early detection of optic glioma.

Results: One hundred and sixty-eight eyes of 85 children were included. The mean follow-up of the patients was 8 ± 3.7 years (range: 2-19 years) and mean age at baseline was 3.1 ± 2.6 years. Mean (±SD) BCVA was 0.19 (±0.20) logMAR at baseline. 16.5% of patients showed the presence of optic nerve abnormalities, 18.8% had therapy, 32.9% of the patients had cafe au lait stains, and 37.1% had Lisch nodules in the eye examination. Worse BCVA at baseline was associated with the presence of severe optic nerve abnormalities (mean 0.21 ± 0.14 logMAR; p < 0.01), compared to patients without optic nerve abnormalities (mean 0.14 ± 0.14 logMAR). Additionally, BCVA at baseline was dependent on the visual test (from mean 0.04 ± 0.19 logMAR to mean 0.3 ± 0.16 logMAR; p < 0.01). There was also a significant difference in BCVA change to follow-up in patients who received therapy compared to patients who did not (p = 0.033). The age showed no significant influence on the BCVA at baseline (p = 0.92).

Conclusions: Optic nerve glioma poses a significant threat to vision in NF1 patients, necessitating biannual follow-up until age 6, including MRI, fundoscopy, and OCT imaging.