Automatic Three-Dimensional Magnetic Resonance-based measurements of tumour prominence and basal diameter for treatment planning of uveal melanoma

•Three-dimensional definitions of eye tumour thickness and diameters were composed.•In general, these measurements agreed with conventional two-dimensional ultrasound.•Magnetic resonance imaging was more accurate when tumours were not completely visible on ultrasound.•Automatic measurements on contrast-enhanced T1-weighted images are preferred.