Intracameral Perfluoropropane Gas in the Treatment of Acute Corneal Hydrops

Pneumodescemetopexy with perfluoroethane (C2F6) for the treatment of acute hydrops secondary to keratoconus

“…The reported overall prevalence of acute hydrops in keratoconus is around 2-3%. 7,11 Despite its self-limiting nature, the time for resolution of corneal oedema may take up to 36 weeks when managed conventionally with topical medications with or without bandage contact lens. 12 Prolonged corneal oedema can potentially increase the risk of corneal neovascularisation, which is a significant risk factor for graft rejection, microbial keratitis, and corneal perforation.…”

“…12 Prolonged corneal oedema can potentially increase the risk of corneal neovascularisation, which is a significant risk factor for graft rejection, microbial keratitis, and corneal perforation. 7,13,14 Feder et al 13 reported that six (66.7%) of their patients with acute hydrops developed stromal neovascularisation when managed with topical medications. Also, acute hydrops typically affects the younger patients, posing negative impacts on the economy and the patient's quality of life.…”

“…This has prompted the idea of using a longer-acting agent like C 3 F 8 gas to prolong the mechanical tamponading action in the anterior chamber. 6,7,16 Rajaraman et al 6 and Basu et al 7 both reported that single injection of intracameral C 3 F 8 gas was sufficient to treat the acute hydrops whereas Sharma et al 16 reported that five (35.7%) of their patients required repeated injections of intracameral C 3 F 8 gas.…”

“…However, there is emerging evidence suggesting that an earlier resolution of corneal oedema could be facilitated by intracameral injection of air, 2 sulphur hexafluoride (SF 6 ) 3,4 and perfluoropropane (C 3 F 8 ) gas. [5][6][7] The proposed mechanism is that the intracameral air or gas acts as a mechanical tamponade, helping the apposition of the Descemet's membrane and creating a barrier to prevent the entry of aqueous into the cornea. However, each of these intracameral substitutes has its inherent problems.…”

“…7,8 Lincoff et al 9 compared the intravitreal longevity of the perfluorocarbons and showed that carbon tetrafluoride had the longevity characteristics similar to those of SF 6 gas, whereas perfluoroethane (C 2 F 6 ) persisted 2.6 times longer than SF 6 and C 3 F 8 remained approximately four times longer. Perfluorocarbon of intermediate duration (ie, C 2 F 6 ) may have an advantage over SF 6 and C 3 F 8 gases and could potentially address the short-acting property of SF 6 gas and the risk of pupillary block and potential cataract formation encountered with C 3 F 8 gas.…”