Primary Vitrectomy With Silicone Oil or SF6 for Rhegmatogenous Retinal Detachment

August 29, 2023 updated by: Mina Safe Abdelmesih Abdelmalak, Cairo University

Macular Perfusion and Sensitivity Following Silicone Oil Tamponade Versus SF6 Gas for Primary 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.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

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.

Study Type

Interventional

Enrollment (Actual)

62

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Egypt
      • Cairo, Egypt, 11956
        • Faculty of medicine, Cairo University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

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

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Silicone oil group
Primary pars plana vitrectomy will be performed and silicone oil will be used as the tamponading agent. For these patients, optical coherence tomography (OCT) and angiography (OCTA), along with microperimetry will be done 2 months after the primary surgery. Then they will be scheduled for silicone oil removal after 3 months from the time of primary surgery. Finally, the OCT, OCTA, and microperimetry will be repeated once more after 4 months from the vitrectomy (i.e. one month after the silicone oil removal).
Procedure: Pars plana vitrectomy with silicone oil
Silicone oil will be used at the end of primary vitrectomy. OCT, OCTA and microperimetry will be done 2 months later. Silicone oil will be removed at 3 months. Finally, the OCT, OCTA, and microperimetry will be repeated once more after 4 months from the vitrectomy.
Active Comparator: Sulfur hexafluoride (SF6) group
Primary pars plana vitrectomy will be performed and sulfur hexafluoride (SF6) will be used as the tamponading agent. For these patients, optical coherence tomography (OCT) and angiography (OCTA), along with microperimetry will be done 2 months and 4 months after the primary surgery.
Procedure: Pars plana vitrectomy with SF6
Sulfur hexafluoride (SF6) will be used at the end of primary vitrectomy. OCT, OCTA, and microperimetry will be done 2 months and 4 months after surgery.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Macular perfusion - FAZ
Time Frame: At 2 and 4 months following primary vitrectomy
Comparison of foveal avascular zone area between the different treatment arms as a measure of macular perfusion.
At 2 and 4 months following primary vitrectomy
Macular perfusion - SVP
Time Frame: At 2 and 4 months following primary vitrectomy
Comparison of superficial retinal capillary vascular density between the different treatment arms.
At 2 and 4 months following primary vitrectomy
Macular perfusion - DVP
Time Frame: At 2 and 4 months following primary vitrectomy
Comparison of deep retinal capillary vascular density between the different treatment arms.
At 2 and 4 months following primary vitrectomy

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Macular sensitivity
Time Frame: At 2 and 4 months following primary vitrectomy
Comparison of macular sensitivity between the different treatment arms using macular microperimetry.
At 2 and 4 months following primary vitrectomy
Thickness of ganglion cell complex
Time Frame: At 2 and 4 months following primary vitrectomy
Comparison of the thickness of ganglion cell complex in microns between the different treatment arms using optical coherence tomography (OCT)
At 2 and 4 months following primary vitrectomy
Best corrected visual acuity
Time Frame: At 2 and 4 months following primary vitrectomy
Comparison of best corrected visual acuity between the different treatment arms using standard Snellen charts.
At 2 and 4 months following primary vitrectomy
Retinal reattachment rate
Time Frame: At 4 months following primary vitrectomy
Comparison of single-operation anatomical success (retinal reattachment) rate between the different treatment arms
At 4 months following primary vitrectomy

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Cairo University

Investigators

  • Principal Investigator: Mina S. Abdelmalak, MSc, Cairo University
  • Study Chair: Soheir M. Mahmoud, PhD, Cairo University
  • Study Director: Ahmed A. Abdel Kader, PhD, Cairo University
  • Study Director: Asmaa M. Shuaib, PhD, Cairo University
  • Study Director: Ayman G. Elnahry, PhD, Cairo University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

December 23, 2021

Primary Completion (Actual)

March 8, 2023

Study Completion (Actual)

May 8, 2023

Study Registration Dates

First Submitted

February 13, 2022

First Submitted That Met QC Criteria

May 16, 2022

First Posted (Actual)

May 17, 2022

Study Record Updates

Last Update Posted (Estimated)

August 31, 2023

Last Update Submitted That Met QC Criteria

August 29, 2023

Last Verified

August 1, 2023

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • MD-187-2021

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

IPD Plan Description

Results will be posted on clinicaltrials.gov when the study is concluded.

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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