The silicon oil needs to be removed only if there is emulsification. If the oil is clear, it can be left in situ. The eye pressure needs to be monitored regularly as long as the oil is in the eye. If the oil is emulsified, it needs to be removed. This could happen anywhere between 6 months to several years after the primary surgery. The retina is usually stable and does not redetach at this time, if successfully attached. In a few eyes, if there is a risk if redetachment, the oil can be removed and replaced with fresh oil. It may also be a good idea to replace the emulsified oil with intraocular gas and observe for stability of your retina over the next few weeks. Best wishes.