Patrick W. Hales1, Kshitij Mankad2, Patricia O'Hare2, Victoria Smith2, Darren Hargrave2, and Christopher Clark1
Conventional MRI sequences have so far failed to
provide imaging biomarkers that reliably differentiate asymptomatic optic
pathway glioma (OPG) tumours from those which cause visual impairment. ADC maps
are now acquired as standard in most institutions, and despite their typically
limited resolution, may provide quantitative assessment of tumour invasion of
the optic nerve. We measured ADC and optic nerve thickness using standard
clinical imaging sequences in OPG patients, in conjunction with visual
assessment. We found that the product of ADC and nerve thickness showed a
significant correlation with visual acuity, and was significantly increased in
patients who had gone blind.
