Reversible expandable pupil expander

A reversible pupil expansion device configured for placement at a pupillary margin, the reversible pupil expansion device comprising:

• a resilient ring body defining a central aperture;
• and
• at least four flanges and at least four notches arranged alternately around a perimeter of the ring body, wherein
• at least two of the flanges are non-folded flanges defining a plane of the device,
• at least two other flanges are folded flanges that are folded radially inward toward the central aperture in a resting state,
• the notches open radially outward away from the central aperture, and each of the notches comprises an outward opening and an inward bulbous receptacle configured to engage a pupillary margin,
• each folded flange is configured to adopt a folded configuration in the resting state and an unfolded configuration in response to radially outward forces, and
• the folded flanges are elastically biased to automatically return to the folded configuration upon release of the forces, thereby reversibly enlarging the central aperture.