Abstract Listings 2024 – European Society of Ophthalmic Plastic and Reconstructive Surgery

Visual and radiological response assessment after various therapy in isolated pediatric optic nerve gliomas: a national retrospective cohort study

Author: Carlien Bennebroek
Base Hospital / Institution: Amsterdam UMC

Rapid fire oral presentation

Abstract ID: 24-210

Purpose

Pediatric isolated optic nerve glioma (ONG) is a rare low grade condition. Treatment is indicated in case of significant radiological progression, decrease visual function or hindering proptosis. Currently, treatment consists of various modalities as no international consensus exists on the optimal treatment approach.

Methods

We conducted a national retrospective multicenter cohort study (1995-2020) and literature search (1970- 2024) to assess treatment response after systemic anticancer therapy (SAT), surgery, and radiotherapy for ONG. The primary endpoints included changes in best-corrected visual acuity (BCVA) and tumor volume (TV) on MRI, both evaluated at the start, end of therapy, and long-term follow up.

Results

The combined results of the cohort study (n=21 ONGs) and 2 studies (n=10/ n=11 ONGs) included after the literature research included response analysis after SAT (n=22), surgery (n=9) and radiotherapy (n=7). After SAT BCVA stabilized or improved in 11 ONGs (78.6%) after long-term follow up, but severe visual impairment or blindness was present in 10 ONG (45.5%) in total. The TV decreased by a median of 45.1% (range: -88.6% to +31.5%) (n=13). Complete resection led to a decrease of BCVA in 62.5%, resulting in blindness of all involved eyes (n=9). First-line RT resulted in a decrease of BCVA (range 0.0- 1.3 LogMAR) in 85.7%, represented by counting fingers or less (≥ 2.0 LogMAR) (n=7). Longitudinal analysis of TV showed a median of 47.3% (range: -42.8% to +245.1%) < 3 months after cessation of RT (n=3), followed by a decrease of 94.4% and 13.8% (n=2).

Conclusion

So far, SAT should be considered the preferred treatment approach in case of potential preservation or improvement of visual function, regardless of the progression of 1 out of 5 ONG. Complete resection of ONG appears effective in alleviating (painful) proptosis in case of pre-existing blindness. Radiotherapy should be avoided due to the high risk of severe VI & blindness, along with the potential for secondary complications.