Gas used in retinal tamponade: (D. REPEAT 2013)
Ref: Kan ski Clinical Ophthalmology, 6th edition. Pages 727-728; Modern Ophthalmology, 3rd edition. L.C. Dutta, Pages 1753-1755Explanation:INDICATION FOR TAMPONADES1 To achieve the retinal flattening by replacing the vitreous.2 To drain the subretina] fluid.3 To provide the internal tamponade of retinal breaks during the postoperative period.TypesExpanding gases:GasesExpansion at 100%Duration of actionConcentration used %Sulphur Hexachloride(SF6)2 times10-14 days20-30%Perlluorethane (C2F6)3 times32-35 days Perlluiropropane (C3F8)4 times55 -65days12-16%Indication: Superior retinal breaks (Gas will be floating).Post operative: Patient must maintain a particular head position to prevent pupillary block glaucoma and to give the appropriately directed buoyancy effect.Silicone Oil: Low specific gravity.Acts as tamponade, prevents migration of proliferative cells and biochemical mediator like VEGF within the vitreous cavity and provides hemostasis during surgery.Complication:Emulsification - Inverse hypopyon (the emulsified silicone oil is called hyperleon).Cataract.Glaucoma.Perfluorocarbon LiquidsHigh specific gravity - it sinks.Uses: Displaces the subretinal fluid, unfolds the Hup during surgeries. Hence it is also called as Third Hand.E.g. Perfluorobutylamine, perfluoron octane, perfluorodecalen.
SF6 (sulfur hexafluoride)
Ethylene oxide
Nitrous oxide
CO2
Retinal Detachment