Image-based ocular proton therapy: MRi in treatment planning and evaluation

Abstract

Uveal melanoma is a rare eye cancer affecting around 200–250 people annually in the Netherlands. Treatment typically involves radiation therapy or removal of the eye. For larger tumours or those near the optic nerve, proton therapy is preferred. Although effective, this treatment often leads to vision loss and currently requires surgery to place metal clips for accurate target delineation and positioning.

This thesis is part of a broader effort to improve proton therapy accuracy and eliminate the need for these clips, focusing on the use of ocular MRI. The research shows that MRI provides geometrically accurate images suitable for treatment planning. Comparisons with conventional methods, such as ultrasound, reveal that MRI offers similar measurements, with higher accuracy for tumours located at the front of the eye.

The studies also demonstrate that commonly used tumour models tend to overestimate tumour size, potentially reducing treatment precision. Additionally, functional MRI scans can detect changes after radiation therapy.