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Retinal detachment is an acute condition in ophthalmology that needs an immediate surgical management. The treatment requires a replacement of the vitreous with a temporary substitute, usually based on a silicone oil. A certain number of patients experience adverse events during the treatment. It seems this phenomenon is related to the formation of emulsions in the affected eye. These appear macroscopically as heterogeneities resembling small droplets with a patchy occurrence in the vitreous substitute. Their existence represents a major complication that may lead to loss of vision. The heterogeneities are transported to regions of the eye in which they cause irreversible damage. The current state of knowledge describes the phenomenon and recommends certain intervention procedures. Here, specific attention is paid to the chemical engineering aspects of the utilization of silicone oils for the treatment of the retinal detachment. It is very likely that the process of tiny droplet formation leading to the development of emulsions is substantially controlled by the hydrodynamic conditions in the eye. The complexity of this statement is examined in this review text. [ABSTRACT FROM AUTHOR]

The shape oscillations of a bubble, which is attached to a tip of a capillary tube, are studied experimentally. It is observed that the attachment leads to an appearance of an additional low-frequency mode (denoted as mode 1), when compared to standard theories of oscillations of free bubbles or drops (e.g., Miller & Scriven, 1968). It is observed that the frequency of mode 1 scales with the bubble size as f ~ D-2. The oscillation dynamics of a bubble is strongly influenced if some surface active agent is present in the liquid. Due to interfacial elasticity, the surfactants presence in low concentration increases the oscillation frequency. The decay of oscillations is also faster, probably due to an increase of energy dissipation by Marangoni stresses.