[Heavy silicone oil as internal tamponade for retinal detachment: efficacy and tolerance]

Comparative Biochemical Outcomes, Effectiveness and Tolerance of Densiron 68 and Oxane HD for the Management of Complicated Retinal Detachment

Objectives:

To compare biochemical outcomes, effectiveness, and tolerance of two high-density silicone oils (HDSOs), silicone oil- RMN3 (Oxane^® HD) and silicone oil-Densiron-68 (Densiron^® 68), for the management of complicated retinal detachment (RD) associated with inferior proliferative vitreoretinopathy (PVR).

Materials and Methods:

This was a retrospective, single-centre, comparative case series of 23 patients treated between September 2014 and June 2016. The main inclusion criteria were RD with inferior PVR receiving Oxane^® HD or Densiron^® 68 following pars plana vitrectomy. The main outcome measures were anatomical success, rate of RD recurrence, and best-corrected visual acuity (BCVA) at 6 months. Secondary outcomes were short-term complications.

Results:

Twenty-three eyes were included: 16 eyes with Densiron^® 68 tamponade and 7 eyes with Oxane^® HD tamponade. Anatomical success under HDSO was significantly higher in the Densiron^® 68 group (100%) than in the Oxane^® HD group (42.8%) (p=0.0455). Recurrent RD was observed in 42.8% of eyes under Oxane^® HD, but in none of the patients under Densiron^® 68 (p=0.001). Six months after surgery, mean BVCA values (+/- standard deviation) with Densiron^® 68 and Oxane^® HD were 0.83±0.62 logMAR and 1.81±0.65 logMAR, respectively. BVCA was significantly better in the Densiron^® 68 group (p=0.006). No significant differences were observed with regard to intraocular pressure, emulsification, or intraocular inflammation.

Conclusion:

Densiron^® 68 appears to be more effective than Oxane^® HD for the management of RD associated with PVR. A randomized, controlled, interventional study is needed to demonstrate this difference.

Advances in the treatment of rhegmatogenous retinal detachment

The pathogenesis of rhegmatogenous retinal detachment depends on three factors, namely, retinal rupture, vitreous liquefaction and traction causing the retina to separate from the pigment epithelium, among which retinal rupture is the most important. Retinopathy is caused by a gap between the neurosensory retina and the retinal pigment epithelium, which severely damages the visual function of the patient. Therefore, early clinical discovery, prevention and selection of an appropriate treatment are important. This article reviews progress in the treatment of retinal detachment.

Heavy silicone oil and intraocular inflammation

In the past two decades, many advances have been made in vitrectomy instrumentation, surgical techniques, and the use of different tamponade agents. These agents serve close retinal breaks, confine eventual retinal redetachment, and prevent proliferative vitreoretinopathy (PVR). Long-acting gases and silicone oil are effective internal tamponade agents; however, because their specific gravity is lower than that of the vitreous fluid, they may provide adequate support for the superior retina but lack efficacy for the inferior retina, especially when the fill is subtotal. Thus, a specific role may exist for an internal tamponade agent with a higher specific gravity, such as heavy silicone oils (HSOs), Densiron 68, Oxane HD, HWS 45-300, HWS 46-3000, and HeavySil. Some clinical evidence seems to presume that heavy tamponades are more prone to intraocular inflammation than standard silicone if they remain in the eye for several months. In this review, we discuss the fundamental clinical and biochemical/molecular mechanisms involved in the inflammatory response after the use of heavy tamponade: toxicity due to impurities or instability of the agent, direct toxicity and immunogenicity, oil emulsification, and mechanical injury due to gravity. The physical and chemical properties of various HSOs and their efficacy and safety profiles are also described.

Heavy Silicone Oil as a Long-Term Endotamponade Agent for Complicated Retinal Detachments

We retrospectively evaluated a heavy silicone oil (HSO) as a long-term intraocular endotamponade agent to treat complicated RD by inferior PVR in 25 eyes of 25 patients. Patients underwent PPV and injection of Oxane HD as an internal tamponade agent. A comparison of preoperative and postoperative BCVA at month 1, month 6, and last visit was made in the group in which HSO was removed and in the group in which HSO was not removed. Statistical calculations were performed using the Wilcoxon test. The HSO was removed from 11 patients after a mean of 26.55 ± 21.38 months. The HSO remained inside the vitreous cavity in 14 eyes due to a high chance of PVR recurrence (mean follow-up period, 11.07 ± 7.44 months). Anatomic success was achieved in 92%. The BCVA in the group, in which HSO was not removed, improved significantly during the first 6 months. Among the patients who had the oil removed, there was improvement in BCVA after 1 month. Oil emulsification was the most common adverse effect in 52% of eyes. HSO is an effective tamponade in complex rhegmatogenous and tractional RD complicated by PVR. HSO can remain in the eye for long periods with relative tolerability and safety.

Residual bubble of oxane hd: a study by optical coherence tomography and fundus-related perimetry

PURPOSE

Oxane HD is a mixture of silicone oil and a mixed fluorinated and hydrocarbonated olefin. The authors report a complication of Oxane HD as internal tamponade after removal of all visible heavy silicone oil.

METHODS

A 71-year-old man who underwent vitrectomy with Oxane HD presented with adherence of a residual bubble of Oxane HD in the macula after removal of all visible heavy silicone oil. In this patient OCT displayed an optical artifact due to the residual bubble, and fundus-related perimetry revealed a predominantly eccentric and relatively unstable fixation and very low macular sensitivity.

RESULTS

After surgical removal of the residual bubble, metamorphopsia resolved, sensitivity improved as revealed by fundus-related perimetry, and fixation became predominantly central and more stable.

CONCLUSION

The authors suggest a way to manage this rare complication of Oxane HD as internal tamponade after removal of all visible heavy silicone oil.