Brief Title
Selective Retinal Pigment Epithelium Laser Therapy for Macular Disease of the Retina
Official Title
Selective Retinal Pigment Epithelium Laser Therapy (SRT) for Macular Disease of the Retina
Brief Summary
Laser photocoagulation of the retina targeting the outer layers is an established therapy for
proliferative retinopathy and macular edema from diabetic microangiopathy or retinal vein
occlusion, centrals serous retinopathy, and extrafoveal subretinal neovascular membranes.
However, collateral damage occurs and scotomas can result when using conventional lasers with
pulse duration of 100ms and more. This is particularly relevant for laser treatments of the
macula where the main therapeutic effect results from stimulation of the retinal pigment
epithelium cells and photoreceptor damage is thought to be an unnecessary side effect. Recent
experimental research with new laser devices using much shorter pulse duration has shown that
photoreceptor damage can be greatly reduced and the retinal pigment epithelium selectively
targeted, hence the term selective retinal pigment epithelium laser therapy (SRT).
Investigators hypothesize that SRT is equally effective as standard laser photocoagulation
for macular disease but minimizes local visual field defects.
In this study, patients with central serous retinopathy, macular edema from diabetic
microangiopathy or branch vein occlusion, and non-exudative age-related macular degeneration
will be treated with SRT. Patients will be assessed 1, 3 and 6 months after treatment.
Detailed Description
Background
Laser photocoagulation of the retina targeting the outer layers is an established therapy for
proliferative retinopathy and macular edema from diabetic microangiopathy or retinal vein
occlusion, centrals serous retinopathy, and extrafoveal subretinal neovascular membranes.
However, collateral damage occurs and scotomas can result when using conventional lasers with
pulse duration of 100ms and more. This is particularly relevant for laser treatments of the
macula where the main therapeutic effect results from stimulation of the retinal pigment
epithelium cells and photoreceptor damage is thought to be an unnecessary side effect. Recent
experimental research with new laser devices using much shorter pulse duration has shown that
photoreceptor damage can be greatly reduced and the retinal pigment epithelium selectively
targeted, hence the term selective retinal pigment epithelium laser therapy (SRT). In
age-related macular degeneration, regression of drusen has been observed after laser
treatment with convention laser or SRT. Investigators hypothesize that SRT is equally
effective as standard laser photocoagulation for macular disease but minimizes local visual
field defects.
Objective
To assess the efficacy of SRT in patients with central serous retinopathy, macular edema from
diabetic microangiopathy or branch vein occlusion, and non-exudative age-related macular
degeneration. Up to five patients with proliferative diabetic retinopathy can optionally be
treated with SRT too.
Methods
At baseline and during follow-up patients will receive a full ophthalmic examination
including optical coherence tomography, fundus autofluorescence imaging, fluorescein
angiography (FA), and visual acuity testing. SRT (R:GEN Laser System by Lutronic Corporation,
Korea) will be delivered under topical anesthesia. For titration of energy spots will first
be applied outside the major arcades. Immediately thereafter FA will be performed for
extrapolation of the laser dose, since the treatment is sub-threshold and laser spots will
not be visible biomicroscopically. The patient will then be treated at the discretion of the
ophthalmologist with up to 500 laser burns. One hour after the laser treatment FA will be
repeated to confirm the treatment effect. Patients will be assessed 1, 3 and 6 months after
treatment. Pulse duration can be chosen between 200ns and 2μs. The maximum pulse energy will
be 1mJ. 1-30 pulses will be applied for every laser burn at a frequency of 100Hz.
Study Type
Interventional
Primary Outcome
Visual Acuity according to ETDRS protocol
Secondary Outcome
Retinal thickness measured by optical coherence tomography
Condition
Macular Edema
Intervention
Selective retinal pigment epithelium laser therapy using the R:GEN Laser System
Study Arms / Comparison Groups
Treatment
Description: Patients receive selective retinal pigment epithelium laser treatment
Publications
* Includes publications given by the data provider as well as publications identified by National Clinical Trials Identifier (NCT ID) in Medline.
Recruitment Information
Recruitment Status
Device
Estimated Enrollment
100
Start Date
June 2010
Completion Date
December 2020
Primary Completion Date
December 2020
Eligibility Criteria
Inclusion Criteria:
- Age 18 or over
- Written informed consent
- Willingness to attend follow-up visits
- Central serous chorioretinopathy affecting visual acuity
- Macular edema from branch retinal vein occlusion
- Macular edema from diabetic microangiopathy
- Age-related macular degeneration with confluent soft drusen
- Age-related macular degeneration with geographic atrophy
Exclusion Criteria
- Macular ischemia
- Retinal hemorrhage impeding retinal laser treatment
- Subretinal neovascular membrane
- Vitreous hemorrhage
- Allergy to fluorescein
- Participation in other clinical trials
Gender
All
Ages
18 Years - N/A
Accepts Healthy Volunteers
No
Contacts
Sebastian Wolf, ,
Location Countries
Switzerland
Location Countries
Switzerland
Administrative Informations
NCT ID
NCT02088151
Organization ID
003/10
Secondary IDs
2011-MD-0006
Responsible Party
Sponsor
Study Sponsor
University Hospital Inselspital, Berne
Study Sponsor
Sebastian Wolf, Study Chair, Department of Ophthalmology, Bern University Hospital
Verification Date
October 2019