Measuring eye deformation between planning and proton beam therapy position using magnetic resonance imaging

Myriam G Jaarsma-Coes; Marina Marinkovic; Eleftheria Astreinidou; Megan S Schuurmans; Femke P Peters; Gregorius P M Luyten; Coen R N Rasch; Jan-Willem M Beenakker

doi:10.1016/j.phro.2020.09.010

Measuring eye deformation between planning and proton beam therapy position using magnetic resonance imaging

Phys Imaging Radiat Oncol. 2020 Oct 6:16:33-36. doi: 10.1016/j.phro.2020.09.010. eCollection 2020 Oct.

Authors

Myriam G Jaarsma-Coes^{1

2}, Marina Marinkovic¹, Eleftheria Astreinidou³, Megan S Schuurmans², Femke P Peters³, Gregorius P M Luyten¹, Coen R N Rasch³, Jan-Willem M Beenakker^{1

2}

Affiliations

¹ Ophthalmology, Leiden University Medical Centre, Leiden, Netherlands.
² Radiology, C.J. Gorter Centre for High Field MRI, Leiden University Medical Centre, Leiden, Netherlands.
³ Radiotherapy, Leiden University Medical Centre, Leiden, Netherlands.

Abstract

Proton beam therapy (PBT) for uveal melanoma (UM) is performed in sitting position, while the acquisition of the Magnetic resonance (MR)-images for treatment planning is performed in supine position. We assessed the effect of this difference in position on the eye- and tumour- shape. Seven subjects and six UM-patients were scanned in supine and a seating mimicking position. The distances between the tumour/sclera in both positions were calculated. The median distance between both positions was 0.1 mm. Change in gravity direction produced no substantial changes in sclera and tumour shape, indicating that supinely acquired MR-images can be used to plan ocular-PBT.

Keywords: Eye deformation; Gravity; MRI; Ocular imaging; Therapy planning; Uveal melanoma.