A Pilot Study of Laser Photocoagulation for Diabetic Macular Edema
试验速览
- 阶段
- 2 期
- 状态
- 已完成
- 发起方
- 入组人数
- 263
- 主要终点
- Change in the central subfield of the ETDRS grid measured by OCT.
研究概览
简要总结
This pilot study will compare the use of current laser treatment for diabetic macular edema with a similar laser treatment that is milder in intensity, but more extensive.
详细描述
Diabetic retinopathy is a disorder of major public health importance, accounting for the majority of visual loss among working age Americans. Diabetic macular edema (DME) is a manifestation of diabetic retinopathy that produces loss of central vision. Data from the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR) estimate that after 15 years of known diabetes, the prevalence of diabetic macular edema is approximately 20 percent in patients with type 1 diabetes mellitus (DM), 25 in patients with type 2 DM who are taking insulin, and 14 percent in patients with type 2 DM who do not take insulin. The Early Treatment Diabetic Retinopathy Study (ETDRS) showed that moderate vision loss, defined as a doubling of the visual angle (e.g., 20/20 reduced to 20/40), can be reduced by 50 percent or more by focal/grid laser photocoagulation according to ETDRS protocol. Although several treatment modalities are currently under investigation, the only demonstrated means to reduce the risk of vision loss from diabetic macular edema are ETDRS laser photocoagulation, as demonstrated by the ETDRS, and intensive glycemic control, as demonstrated by the Diabetes Control and Complications Trial (DCCT) and the United Kingdom Prospective Diabetes Study (UKPDS). In the DCCT, intensive glucose control reduced the risk of onset of diabetic macular edema by 23 percent compared with conventional treatment. Long-term follow-up of patients in the DCCT show a sustained effect of intensive glucose control, with a 58 percent risk reduction in the development of diabetic macular edema for the DCCT patients followed in the Epidemiology of Diabetes Interventions and Complications Study.
In brief, the study protocol involves the enrollment of patients >18 years of age who have DME involving or threatening the center of the macula and who have not had prior focal/grid laser photocoagulation for DME. These are patients for whom the standard of care would be to treat with laser photocoagulation. Eligible eyes will be randomly assigned to receive either the modified-ETDRS technique or the mild macular grid (MMG) technique. Outcome assessments will include Optical Coherence Tomography (OCT), fundus photography, fluorescein angiography and standardized best-corrected visual acuity.
The study consists of two phases: Phase 1 (the primary study), which consists of the first 12 months of follow up, during which a structured protocol is followed; and Phase 2, which consists of the second and third years of follow up, during which the management of DME can include techniques other than laser photocoagulation, at discretion of the investigator.
During Phase 1, follow-up visits will occur at 15 weeks (3.5 months) +14 days, 34 weeks (8 months) + 28 days, and 52 weeks (12 months) + 28 days. The primary outcome for phase 1 is at 12 months.
The primary study objectives of Phase 1 include:
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Single (Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age >= 18 years. Patients <18 years old are not being included because diabetic macular edema (DME) is so rare in this age group that the diagnosis of DME may be questionable.
- •Diagnosis of diabetes mellitus (type 1 or type 2)
- •Any one of the following will be considered to be sufficient evidence that diabetes is present:
- •Current regular use of insulin for the treatment of diabetes; Current regular use of oral antihyperglycemia agents for the treatment of diabetes; Documented diabetes by ADA guidelines (see DRCR.net Procedures Manual).
- •No history of renal failure requiring dialysis or renal transplant.
- •No condition that in the opinion of the investigator would preclude participation in the study (e.g., unstable medical status including blood pressure and glycemic control; Patients in poor glycemic control who recently initiated intensive insulin treatment (a pump or multiple daily injections) or plan to do so in the next 3 months should not be enrolled.
- •Ability and willingness to provide informed consent.
- •No expectation that subject will be moving out of the area of the clinical center to an area not covered by another clinical center during the next 12 months.
- •Study Eye Criteria:
- •At least one eye must meet all of the following criteria:
- •Best corrected Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity score >= 19 letters (approximately 20/400 or better).
- •Definite retinal thickening due to diabetic macular edema based on clinical exam at or within 500 microns of the macular center for which the investigator believes laser photocoagulation is indicated.
- •A thickness of 250 microns or more in the central subfield OR a thickness of 300 microns or more in any one of the four subfields directly adjacent to the central subfield on optical coherence tomography (OCT).
- •No prior focal/grid laser photocoagulation in the macula.
- •No prior medical treatment for DME (e.g., intravitreal/peribulbar steroids).
- •No panretinal scatter photocoagulation (PRP) within prior 4 months.
- •No anticipated need for PRP within next 4 months.
- •No major ocular surgery (including cataract extraction, any other intraocular surgery, scleral buckle, glaucoma filter, cornea transplant, etc.) within prior 6 months.
- •No Nd:YAG laser capsulotomy within prior 2 months.
- •Macular edema is not considered to be due to a cause other than diabetic macular edema. An eye should not be considered eligible (1) if the macular edema is considered to be related to cataract extraction or (2) clinical exam and/or OCT suggests that vitreoretinal interface disease (eg. vitreo-retinal traction or epriretinal membrane) is the primary cause of the macular edema.
- •Media clarity, pupillary dilation, and patient cooperation sufficient for adequate fundus photos.
- •No ocular condition (other than diabetes) that, in the opinion of the investigator, might affect macular edema or alter visual acuity during the first 12 months of the study (e.g., vein occlusion, uveitis or other ocular inflammatory disease, neovascular glaucoma, Irvine-Gass Syndrome).
- •Glaucoma per se is not an exclusion.
- •A patient may have two "study eyes" only if both are eligible at the time of randomization. An eye that becomes eligible after randomization will not be considered a study eye for purposes of data analyses or treatment decisions although information is being gathered on all eyes)
排除标准
- 未提供
结局指标
主要结局
Change in the central subfield of the ETDRS grid measured by OCT.
时间窗: 1 Year
次要结局
- Change in visual acuity(1 Year)
- Change in area of retinal thickening on fundus photographs(1 Year)