Do Daily Activities Impact Gas Tamponade - Retina Contact after Pars Plana Vitrectomy? A Computational Fluid Dynamics Study.

PURPOSE: To calculate the retinal surface alternatively in contact with gas and aqueous due to fluid sloshing during daily activities such as ocular saccade, turning the head, standing up and being a passenger of a braking car.

METHODS: Fluid dynamics of aqueous and gas tamponade were reproduced via computational methods using the OpenFOAM® open-source library. The double-fluid dynamics was simulated by the volume of fluid method and setting the contact angle at the aqueous-gas-retina interface.

RESULTS: Sloshing increased the retinal surface in contact with aqueous by 13-16% regardless of fill rate and standing up determined the largest area of wet retina, followed by car braking, head rotation and ocular saccade (p<0.001). All activities except the ocular saccade determined a significant increase in the surface of retina in contact with the aqueous (p<0.005). Car braking induced the highest shear stress (6.06 Pa); standing up determined the highest SI and saccade the lowest.

CONCLUSION: Daily activities instantaneously reduce the amount of retina consistently in contact with gas tamponade and increase shear stress giving aqueous a potential access to the subretinal space regardless of patients' compliance.