Clinical Trials Logo

Clinical Trial Summary

Hyperbaric chamber treatment assists in increasing the amount of oxygen in the plasma and in the tissues and has been proven to be beneficial in treating different ischemic wounds, and acute retinal artery occlusion (ARAO) but its effect hasn't been tested in CRVO patients yet.


Clinical Trial Description

Trial protocol V2.0 - Hyperbaric chamber treatment to CRVO patients

Assaf HaRofe Medical Center - Zerifin, Israel

Purpose: To determine whether hyperbaric chamber treatment improves the functionality and symptoms related to CRVO

Introduction:

Central Retinal Vein Occlusion (CRVO) has profound effects on retinal circulation. As this vein collects the entire venous outflow from the retina, retinal perfusion is greatly impaired when it occludes. Even though, as compensation, the collateral outflow is expanded but nevertheless there is an increase in retinal venous pressure, venous dilation, retinal hemorrhage and retinal edema.

Reduction of blood flow leads to retinal hypoxia and upregulation of vascular endothelial growth factor (VGEF )

In CRVO there is a variable degree of capillary nonperfusion visible on fluorescein angiography (FA) which is divided into "ischemic" and "non ischemic" depending on the size of the area of non perfusion on FA.

Possible complications of CRVO include chronic cystoid macular edema (CME), neovascularization of retina, neovascular glaucoma and vitreous hemorrhage. These complications are serious, sight threatening, and require prolonged treatment.

Current therapy of CRVO requires different treatment modalities depending on the complication.

Neovascularization is treated mainly by laser photocoagulation (PRP - pan retinal photocoagulation) and VEGF inhibitors. Photocoagulation is based on lowering the oxygen consumption of peripheral retina.

Macular edema is treated with anti VEGF and/or steroidal injections. Most patients require continuous monthly injections which may last for years in order to dehydrate their macula.

Recent clinical trials such as CRUISE and BRAVO have shown that the immediate monthly injections of anti VEGF (Ranibizumab) during the first 6 months and then later as needed decreased substantially the time to achieve visual acuity gain following CRVO5. In BRAVO trial the cumulative proportion of patients who had gained 15 letters or more from baseline by 12 month (from CRVO incidence) was 50% (sham), 68% (ranibizumab 0.3 mg), and 71% (ranibizumab 0.5 mg) and in CRUISE trial 42%, 61%, and 66%, respectively.

Another trial which evaluated the effect of anti VEGF was the COPERNICUS trial in which patients with CRVO received intravitreal aflibercept injection every 4 weeks up to 6 months following the CRVO. The control group received sham injections and the proportion of patients gaining ≥ 15 letters was 56.1% versus 12.3% (P<0.001) at week 24. Improved reduction in central retinal thickness and increased vitreous hemorrhage as the major side effect (up to 6.8%) was also evident in patients treated with aflibercept.

Although effective, these anti VEGF injections expose the patient to many possible side effects including sub conjunctival hemorrhage and transient hypertension at the mild end of the spectrum or endophthalmitis and lens injury at the severe end.

An alternative treatment is the use of steroids such as dexamethasone intravitreal implant (Ozurdex). However, this treatment may induce side effects such as increased ocular pressure, cataract, allergy, conjunctival hemorrhage and eye pain.

Hypoxic induction of cytokines, such as VEGF, play a central role in CRVO and its consequences such as retinal edema and iris neovascularization.

Hyperbaric chamber has the potential to increase oxygen perfusion and perhaps decrease retinal hypoxia, thereby decreasing the induction of cytokines and improving retinal functionality.

The investigators' broad experience in hyperbaric chamber treatment reveals that it is a rather benign treatment compared to the alternatives where the most relevant side effect in eligible patients is usually ear barotrauma.

Investigative Device:

Hyperbaric chamber assists in increasing the amount of oxygen in the plasma and in the tissues and has been proven to be beneficial in treating different ischemic wounds, and acute retinal artery occlusion (ARAO) but its effect hasn't been tested in CRVO patients yet.

Methods:

Patients with chronic CRVO who are receiving monthly injections of Bevacizumab treatment for at least 12 months will be recruited. Upon recruitment each patient will undergo a screening Ophthalmologic examination including visual acuity, refraction and OCT. This will be followed by a series of 40 daily hyperbaric chamber treatments. A repeated ophthalmic examination will be done after 20 and 40 hyperbaric sessions. ;


Study Design

Endpoint Classification: Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment


Related Conditions & MeSH terms


NCT number NCT02405741
Study type Interventional
Source Assaf-Harofeh Medical Center
Contact Rubin, MD
Phone 972-89779720
Email yairub@gmail.com
Status Recruiting
Phase Phase 2
Start date March 2015
Completion date September 2016

See also
  Status Clinical Trial Phase
Completed NCT02390245 - Philadelphia Telemedicine Glaucoma Detection and Follow-Up Study N/A
Completed NCT01969708 - Study of Comparative Treatments for Retinal Vein Occlusion 2 (SCORE2) Phase 3
Completed NCT01231633 - Comparison of Initial Ozurdex (Dexamethasone Implant) to Avastin (Bevacizumab) for Treatment of Macular Edema Caused by Central Retinal Vein Occlusion (CRVO) N/A
Terminated NCT00969293 - Study to Assess the Safety and Tolerability of a Single Administration of FOV2302 (Ecallantide) in Patients With Macular Edema Associated With Central Retinal Vein Occlusion Phase 1
Completed NCT03981549 - Treatment of Central Retinal Vein Occlusion Using Stem Cells Study Phase 1/Phase 2
Completed NCT02274259 - Comparing Injection Frequency Between Aflibercept and Ranibizumab in Patients With CRVO With a Treat& Extend Regimen Phase 4
Completed NCT01360385 - Retinal Ischemia in Central Retinal Vein Occlusion, and the Effects of Treatment With Intravitreal Ranibizumab N/A
Not yet recruiting NCT00383773 - Retinal Endo Vascular Surgery for Central Retinal Vein Occlusion N/A
Completed NCT00952614 - A Study of a Sustained Release Fluocinolone Implant for Treatment of Central Retinal Vein Occlusion N/A
Recruiting NCT04601701 - Central Retinal Vein Occlusion (CRVO) Treatment With Bevacizumab and Dexamethasone or Bevacizumab Only. N/A
Withdrawn NCT03417401 - Surgical Stabilizer Assisted RVC With rtPA for CRVO Phase 1
Completed NCT01976312 - Ranibizumab Intravitreal Injections Versus Sham Control in Patients With Central Retinal Vein Occlusion (CRVO) Phase 3
Completed NCT01724554 - Impact of Intravitreal Aflibercept Injections on Capillary Non-Perfusion Phase 1/Phase 2
Completed NCT01471691 - Intravitreal Ranibizumab 0.5MG, or 1.0mg for RVO With Macular Edema Previously Receiving Bevacizumab Phase 1/Phase 2
Active, not recruiting NCT01011374 - Impact of Lucentis on Psychological Morbidity in Patients With Retinal Vein Occlusion Phase 1
Completed NCT03223714 - Conbercept Ophthalmic Injection for Patients of Central Retinal Vein Occlusion Phase 3
Recruiting NCT01827722 - Ozurdex Versus Ranibizumab Versus Combination for Central Retinal Vein Occlusion Phase 4
Completed NCT00906685 - Bevacizumab for Central Retinal Vein Occlusion Study Phase 3
Active, not recruiting NCT04793100 - Spontaneous Retinal Artery Pulses (SPARs) as a Prognostic Determinant of Central Retinal Vein Occlusions (CRVO) in Patients With or Without Intravitreal Aflibercept Injections N/A
Recruiting NCT01348633 - Retinal Oxygen Saturation, Blood Flow, Vascular Function and High Resolution Morphometric Imaging in the Living Human Eye N/A