Primary Vitrectomy With Silicone Oil or SF6 for Rhegmatogenous Retinal Detachment

Rhegmatogenous retinal detachment (RRD) is the separation of the neurosensory retina from the retinal pigment epithelium caused by the presence of a break that leads to the passage of fluid from the vitreous cavity into the potential subretinal space. It is a sight threatening disease, affecting largely people 50 years or older, with an annual incidence varying between 6.3 and 17.9 people per 100,000 population, and is unfortunately increasing. Although other surgical options do exist for the repair of primary RRD, pars plana vitrectomy (PPV) has clear advantages and is certainly effective in the treatment of these patients.

Several agents are used for intraocular tamponade following PPV for RRD. These agents are either silicone oil (SO) or gases like air, perfluoropropane (C3F8), sulfur hexafluoride (SF6), or perfluoroethane (C2F6).

In addition to the complications uniquely peculiar to using SO, research has found out that a reduction in retinal sensitivity on microperimetry was greater in SO tamponade in comparison with gas, as well as poorer visual outcome, microvasculature damage and affection of retinal layers including ganglion cell complex (GCC) in the SO group.

Even though many studies were done to compare between SO and intraocular gas tamponades with respect to many aspects, only one study compared the effects SO had on macular vasculature and anatomy in comparison with air and no study at all to date has compared the SO to SF6 gas in terms of retinal vascular changes, correlating them to thinning of GCC and macular sensitivity, which is precisely the main aim of the current study.

Rhegmatogenous retinal detachment (RRD) is the separation of the neurosensory retina from the retinal pigment epithelium (RPE) caused by the presence of a break that leads to the passage of fluid from the vitreous cavity into the potential subretinal space. It is a sight threatening disease, affecting largely people 50 years or older, with an annual incidence varying between 6.3 and 17.9 people per 100,000 population, and is unfortunately increasing. Although other surgical options do exist for the repair of primary RRD, viz. scleral buckling and pneumatic retinopexy, primary pars plana vitrectomy (PPV) has clear advantages and is certainly effective in the treatment of these patients, with a primary success rate of 85%, making it the leading management modality.

Several agents are used for intraocular tamponade following PPV for RRD, in order to provide surface tension across the retinal breaks thus preventing the ingress once more of fluid into the subretinal space, giving time for the permanent seal provided by the retinopexy done whether photocoagulation or cryopexy. These agents are either silicone oil (SO) or gases like air, perfluoropropane (C3F8), sulfur hexafluoride (SF6), or perfluoroethane (C2F6).

In addition to the complications uniquely peculiar to using SO, research has found out that a reduction in retinal sensitivity on microperimetry was greater in SO tamponade in comparison with gas, as well as poorer visual outcome, microvasculature damage and affection of retinal layers including ganglion cell complex (GCC) in the former group leading to the so-called Silicone Oil-Related Visual Loss (SORVL).

Even though many studies were done to compare between SO and intraocular gas tamponades with respect to many aspects, only one study by Zhou et al in 2020 compared the effects SO endotamponade had on macular vasculature and anatomy in comparison with sterilized air tamponade and no study at all to date has compared the SO to SF6 gas in terms of retinal vascular changes, correlating them to thinning of GCC and macular sensitivity, which is precisely the main aim of the current study.

Eligibility Criteria:
Inclusion Criteria:

* Primary rhegmatogenous retinal detachment

Exclusion Criteria:

* Macula-on retinal detachment
* Change of decision of type of endotamponade used intraoperatively
* Giant retinal tear
* Proliferative vitreoretinopathy worse than grade B
* Recent lens surgery within the previous 3 months prior to presentation
* Prior vitreoretinal surgery
* Macular hole
* Signs of epiretinal membrane
* Diabetic retinopathy
* Macular degeneration or other macular disorders
* Inferior retinal breaks between 4 and 8 o'clock
* History of uveitis
* History of glaucoma