Which gas is used for Retinal insufflations (Tamponade of retina) ?

Ref: Kanski Clinical Ophthalmology 6th edition; pg no. 727 - 728; Modem Ophthalmology 3rd edition , LC.Dutta, page no 1753 - 1755Explanation:Indication for Tamponades1. To achieve the retinal flattening by replacing the vitreous2. To drain the subretinal fluid3. To provide the internal tamponade of retinal breaks during the postoperative periodTypes:Expanding gases (See the following table /Indication: Superior retinal breaks (Gas will be floating)Post operative: Patient must maintain a particular head position to prevent pupillary block glaucoma & to give the appropriately directed buoyancy effect. SILICONE OIL: Low specific gravity Acts as tamponade, prevents migration of proliferative cells & biochemical mediator like VEGF within the vitreous cavity and provides hemostasis during surgeryComplication:Emulsification - Inverse hypopyon (the emulsified silicone oil is called hyperleon),Cataract,GlaucomaPERFLUOROCARBON LIQUIDS:High specific gravity - it sinksUses: Displaces the subretinal fluid, unfolds the flapduring surgeries. Hence is is also called as THIRDHANDEg. Perfluorobutylamine, perfluoronoctane, peril uorodec ale n