Change in Optic Nerve Head Blood Flow,Optic Nerve Topography and Diurnal Fluctuation of Intraocular Pressure and Pulsatile Ocular Blood Flow in Glaucoma:Cosopt and Xalatan vs Xalatan Alone
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 入组人数
- 25
- 试验地点
- 1
- 主要终点
- Clinical evidence for lower diurnal variational Intraocular Pressure
研究概览
简要总结
Diurnal and intervisit fluctuations in IOP are strongly associated with progression of open angle glaucoma and therefore need to be minimized. Control of diurnal fluctuations of IOP with different ocular hypotensive medications has been studied in some detail. But how do IOP changes contribute to progressive glaucomatous optic nerve damage? It is reasonable to assume that there are two principal effects of IOP changes. First, IOP fluctuations result in changes in the stresses and strains on the ONH which in turn result in morphological changes to the ONH. These morphological changes could in turn result in stretching and damage to axons of the ONH. Secondly, IOP fluctuations results in changes to the forces acting on the ONH vasculature, leading to changes in ONH vascular perfusion. These changes to perfusion could in turn result in relative ischemia of the ONH and consequent ONH damage.
The investigators propose to monitor diurnal fluctuations in IOP and choroidal blood flow (Pulsatile Ocular Blood Flow,POBF), and intervisit ONH topographical and blood flow changes-ie to monitor the direct ONH consequences of IOP . Open angle glaucoma patients are commonly prescribed topical latanoprost as first line therapy. The EXACCT study, for which I was the principal investigator and which is now submitted for publication, demonstrated that COSOPT was an efficacious choice as second line therapy for patients not controlled on latanoprost monotherapy. The investigators will therefore recruit 20 OAG patients on latanoprost monotherapy, perform diurnal curves of IOP, as well as a.m. ONH morphology and ONH blood flow. Cosopt will then be added and at the next visit the same measurements will be repeated.
The investigators expect that when Cosopt is added the investigators will demonstrate improved IOP, morphology and blood flow compared to the latanoprost baseline. Furthermore the investigators expect the the diurnal fluctuation of IOP and choroidal blood flow will be stabilized on Cosopt therapy. The implications are that adding Cosopt to latanoprost can stabilize not only the IOP but also the damaging consequences of IOP to the optic nerve head.
详细描述
Twenty patients with open angle glaucoma or ocular hypertension currently on latanoprost immunotherapy will be recruited.
A complete routine ophthalmic examination including biomicroscopy, gonioscopy and fundus ophthalmoscopy will be performed. The eye with better visual acuity is selected for fundus flowmetry.
All patients will undergo a complete diurnal workup including IOP, as well as 10am Confocal scanning laser ophthalmoscopy (Heidelberg Retina Tomography-3) of ONH topography. Optic nerve head, nasal and temporal peripapillary retinal blood flow are measured with scanning laser Doppler flowmetry (SLDF; Heidelberg Retinal Flowmeter/Tomograph, SLDF analysis software v3.3, Heidelberg Engineering, Germany Goldmann IOP will be measured at 8am, 10am 2pm and 4pm. Pulse amplitude, similar to Pulsatility Ocular Blood Flow (POBF) will be measured using the Pascal Dynamic Contour Tonometer (DCT) at 8am, 10am, 2pm, and 4 pm.
All procedures will conform to the Declaration of Helsinki and the study will be approved by the Ethics Committee and each patient will sign an informed consent form.
Following visit one, Cosopt will be added to the patients therapy (bid). Following 6 weeks of therapy patients will return for visit two. Cosopt will be applied by the investigator at 8am on visit 2.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Other
- 盲法
- None
入排标准
- 年龄范围
- 30 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Subjets with open angle glaucoma or ocular hypertension currently on latanoprost immunotherapy.
- •Subjets must have clear media, corrected visual acuity of 6/12 or better,and be able to sit for imaging.
排除标准
- •Subjets with contraindications or known allergies to any of the components of Cosopt.
- •Subjets who had undergoing laser or any ocular surgery.
研究组 & 干预措施
Cosopt
Cosopt ('Dorzolamide 20 mg and Timolol 5 mg) bid And Xalatan hs Vs Xalatan hs Alone
干预措施: Dorzolamide 20 mg and Timolol 5 mg (Drug)
结局指标
主要结局
Clinical evidence for lower diurnal variational Intraocular Pressure
时间窗: Six weeks
次要结局
- The Intraocular Pressure, Retinal and choroidal blood flow will be stabilized on Cosopt therapy(Six weeks)
研究者
Mark R. Lesk
Director of opthalmology research
Maisonneuve-Rosemont Hospital