Retina_L

Delineation Information

Modality

MR

Guideline

Taken from Eekers DBP, Di Perri D, Roelofs E, Postma A, Dijkstra J, Ajithkumar T, et al. Update of the EPTN atlas for CT- and MR-based contouring in Neuro-Oncology. Radiother Oncol 2021;160:259–65. https://doi.org/10.1016/j.radonc.2021.05.013.

Method

Manual. The retina is a neurosensorial membrane of 2–3 mm thickness, located at the posterior part of the eyeball, posterior to the cornea and lens, and is the innermost of the three layers that form the wall of the eyeball (sclera, uvea/choroid and retina). Using a 3 mm brush, it can be delineated on MR as well as CT as a membrane covering the posterior 5/6 of the globe, extending nearly as far as the ciliary body. The anterior border of the retina is between the insertion of the medial rectus muscle and the lateral rectus muscle, posterior to the ciliary body. The optic nerve is excluded from this contour

Anatomical Boundaries

Cranial

Superior most slice where the retina is visible.

Caudal

Inferior most slice where the cornea is visible.

Medial

The retina is bounded medially by the vitreous cavity

Lateral

Sclera

Ventral

The anterior border of the retina is between the insertion of the medial rectus muscle and the lateral rectus muscle, posterior to the ciliary body.

Additional Metrics