Tumor load rather than contrast enhancement is associated with the visual function of children and adolescents with optic pathway glioma – a retrospective Magnetic Resonance Imaging study

Abstract

Introduction Optic pathway gliomas are often asymptomatic tumors occurring in children with neurofibromatosis type 1 (NF1 + OPG) or sporadically (spOPG). Treatment is usually prompted by visual loss and/or tumor progression on MRI. The aim of this study was to investigate the relationship between visual acuity (VA), tumor growth, and contrast enhancement to provide more distinct indications for the administration of gadolinium-based contrast agents. Methods Tumor load was retrospectively measured and enhancement semi-quantitatively scored on 298 MRIs of 35 patients (63% NF1 + OPG). Spearman rank correlation between tumor load and enhancement was calculated and a linear mixed model used to examine the influence of tumor load and enhancement on corresponding VA tests (LogMAR). Results The optic nerve width in NF1 + OPGs was strongly associated with VA (regression coefficient 0.75; confidence interval 0.61—0.88), but weakly with enhancement (0.06; −0.04—0.15). In spOPGs, tumor volume and optic nerve width were more relevant (0.31; −0.19—0.81 and 0.39; 0.05—0.73) than enhancement (0.09; −0.09—0.27). Conclusions Tumor load measures may be more relevant for the surveillance of optic pathway gliomas than enhancement, given that VA is the relevant outcome parameter. Regular contrast administration should therefore be questioned in these patients.

Optic nerve glioma

“…Ta èiau tam tikrais at ve jais ga li ma at lik ti ir kom piu te ri nae to mog ra fi jà (KT), pa vyz dþiui, esant me ta li niams sve tim kû niams. Taip pat KT ge riau ma to mi kal ci fi ka tai, ku rie daþ niau pa si tai ko ser gant me nin gio ma [4,29].…”

“…RNG gy dy mas yra in di vi du a lus kiek vie nam pa cien tui ir iki ðiol ke lia daug dis ku si jø [4]. Gy dy mas pri klau so nuo to, ar yra kli ni ki niai simp to mai (pro gre suo jan tis re gos funk cijø pa ken ki mas), ir nuo vaiz di niø ty ri mø re zul ta tø [29,30]. Ste bë ji mas ga li bû ti tai ko mas pa cien tams, ku riems ne pa sireið kia jo kie kli ni ki niai simp to mai [31].…”