Comparing the Effectiveness of Phacoemulsification + ECP Laser and Phacoemulsification Alone for the Treatment of Open Angle Glaucoma in Patients With Cataract - a Randomised Controlled Trial
试验速览
- 阶段
- 4 期
- 入组人数
- 160
- 主要终点
- Change in post-washout IOP at 24 months
研究概览
简要总结
Laser endoscopic cyclophotocoagulation (ECP) has been in use for the treatment of glaucoma for over 20 years and is usually used in conjunction with cataract surgery. In the US it is one of the most commonly performed cataract 'plus' surgeries. The take-up of ECP laser has been much lower in the UK and Europe. This is partly due to the lack of robust clinical evidence from randomised controlled trials to justify its use in routine practice. More recently the advent of minimally invasive glaucoma surgery techniques (MIGS) has increased the options available for cataract 'plus' surgery. Without any randomised controlled trial data for the use of ECP laser in this context the increasingly popular use of MIGS devices, such as iStent (the current market leader) may further marginalise the use of ECP laser for cataract 'plus' surgery in patients with Primary Open Angle Glaucoma (POAG) and visually significant cataract.
To further evaluate the use of ECP laser for the treatment of glaucoma in patients with glaucoma and cataract, investigators plan to conduct a randomised controlled trial comparing cataract surgery alone versus cataract surgery plus ECP laser surgery. Investigators will compare the efficacy of these interventions for the treatment of glaucoma based on clinical outcomes and also undertake a cost-benefit analysis, taking into account the cost of surgery, any reduction in clinical time allocation for procedures, the frequency of intra- and post-operative complications, and any reduction in the need for topical glaucoma treatments post-surgery, as well as the frequency with which further glaucoma filtering surgery is needed for patients in each group.
Investigators anticipate that a total number of 160 patients (80 in each arm) will be adequate to detect whether there is any difference in efficacy between cataract surgery + ECP versus cataract surgery alone. Recruitment is expected to take around 9-12 months. Participants will undergo treatment wash-out (28 days minimum) of any eye drops they use for their glaucoma prior to data collection at baseline (before surgery) and prior to data collection at one-year and at two-years post-surgery. Results will be reviewed during an interim analysis at 6 months once 50 patients have reached that time point.
详细描述
The study compares one off surgical interventions that are in routine clinical use and therefore there are no major ethical issues. All participants will be eligible for cataract surgery. Participants will be randomly allocated to one or other of the treatment arms. Explicit written consent for randomisation will be obtained and recorded on the consent form. The available evidence does not indicate that there are substantially greater risks of intra- and post-operative complications associated with combined ECP plus cataract surgery compared with cataract surgery alone.
Participants may be asked to attend an additional visit for the baseline pre-operative data collection. The tests undertaken at this visit would therefore be additional non-routine procedures. If the baseline data collection is undertaken at an additional, rather than a routine visit, then travel expenses to will be paid for the extra non-routine visit.
At the some visits additional tests will be performed that would not normally be routinely undertaken with glaucoma patients at those visits. All of the tests that will be done for the study are routinely performed in ophthalmology out-patient clinics, but the non-routine tests may not be routinely performed with glaucoma patients or may not be routinely performed at all visits.
Participants will be asked to stop using their eye drops for glaucoma at least 28 days before the pre-operative baseline measurements are taken and again at least 28 days before the 1 year and 2 years post-operative measurements are taken (if they continue to need eye drops after surgery). This will not cause participants any harm and will not have a clinical impact on their glaucoma or their vision. Including a treatment washout period is common practice in glaucoma research. If it is not clinically safe for a patient to stop taking the eye drops they use to treat their glaucoma or ocular hypertension for 4 weeks, or if they are not willing to stop using their eye drops for 4 weeks, then they will be excluded from the study. To minimise risk only patients with mild to moderate glaucoma will be included. Those with advanced disease will be excluded. The treatment washout will not cause any delay to the surgery as the usual waiting time for surgery is 1-2 months.
To be on the safe side some participants may be asked to come in two weeks after stopping taking their eye drops so the investigators can do a safety check of the pressure in their eyes. Most patients who take part in the study will not need this. If investigator do ask a participant to come in for a safety check this will be an extra appointment that they would not normally be asked to come to if the participant were not taking part in the study, so the travel expenses will be paid. It will be a brief appointment (10-15 minutes) to check the intraocular pressure by Goldmann applanation tonometry. This is the standard test for intraocular pressure that is performed at all routine glaucoma clinic visits. Participants may potentially need to come in for three IOP safety check visits if a washout is required before the 1 year and 2 years follow-up visits because treatment by eye drops is continued after surgery.
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 (Participant)
入排标准
- 年龄范围
- 40 Years 至 85 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •General inclusion criteria:
- •Male and female patients, from 40 to 85 years of age, inclusive.
- •Patient is able and willing to attend scheduled follow-up examinations as per routine care for 2 year post-operatively.
- •Patient is able to understand the information sheet and give informed consent.
- •Inclusion criteria for the study eye:
- •An operable age-related cataract with BCVA of 6/9 or worse that is eligible for phacoemulsification.
- •A diagnosis of POAG or pigmentary glaucoma treated with hypotensive medications (eye drops for glaucoma).
- •A previously documented unmedicated intraocular pressure of > 21 mmHg (i.e. IOP > 21 mmHg prior to the commencement of glaucoma treatment).
- •An optic nerve appearance characteristic of glaucoma with either:
- •visual field loss (no worse than -12dB) identified on examination using Humphrey 24-2 SITA standard, or
- •(in patients where the VF exam is not confirmatory for glaucomatous defect) OCT retinal nerve fibre layer imaging supporting the ophthalmoscopy findings indicating a diagnosis of mild glaucoma. (If OCT findings are not confirmatory of glaucoma and both the visual field and the OCT are normal, the patient should not be enrolled).
- •Shaffer grade ≥2 in all four quadrants on gonioscopy.
- •Absence of peripheral anterior synechiae (PAS), rubeosis or other angle abnormalities that could impair surgical access to the ciliary processes.
排除标准
- •Diagnosis of Primary angle closure glaucoma.
- •Any diabetic retinopathy.
- •Previous history of Central Serous Retinopathy or Cystoid Macular Oedema in either eye.
- •Congenital or developmental glaucoma.
- •Secondary glaucoma (such as neovascular, uveitic, pseudoexfoliative, lens-induced, steroid-induced, trauma induced, or glaucoma associated with increased episcleral venous pressure).
- •Previous trabeculectomy, tube shunts, or any other prior subconjunctival filtration or cycloderstructive surgery.
- •Inability to complete a reliable 24-2 SITA Standard Humphrey visual field on the study eye at screening (fixation losses, false positive errors and false negative errors should not be greater than 33%).
- •Patients with advanced glaucoma or any patient where the risk to the patient of a washout of ocular hypotensive medications (eye drops for glaucoma) is assessed as unacceptable (i.e. where there may be a risk of damage to vision if treatment is stopped for the washout).
- •Best corrected visual acuity worse than 6/36 in the fellow eye (i.e. not the eye undergoing the study intervention).
- •A 24-2 SITA Standard Humphrey visual field mean deviation (MD) of worse than -12dB in the study eye.
- •Previous vitreo-retinal surgery.
- •Previous corneal surgery or clinically significant corneal dystrophy, e.g. Fuch's dystrophy (>12 confluent guttae).
- •Unclear ocular media preventing visualization of the fundus or anterior chamber angle.
- •Degenerative visual disorders such as wet age-related macular degeneration.
- •Clinically significant ocular pathology other than cataract and glaucoma.
- •Clinically significant ocular inflammation or infection within 1 month prior to screening.
- •Presence of extensive iris processes that obscure visualization of the trabecular meshwork.
- •Uncontrolled systemic disease that in the opinion of the investigator would put the patient's health at risk and/or prevent the patient from completing all study visits.
- •Current participation or participation within the past 30 calendar days in another investigational drug or device clinical trial (which includes the fellow eye).
- •Pregnant or nursing women, or women of child bearing age planning pregnancy or not using medically acceptable contraceptives.
- •Unwilling or unable to give informed consent/unwilling to accept randomisation.
- •Unwilling or unable to return for scheduled protocol visits.
- •Any inclusion criteria not met.
研究组 & 干预措施
Phacoemulsification + ECP laser
Cataract surgery will be performed using standard anesthesia and phacoemulsification techniques. A clear corneal incision should be used for instrumentation. The choice of viscoelastics to maintain the anterior chamber is left to the surgeon's discretion. The viscoelastic will be washed-out of the capsular bag after IOL insertion. Further cohesive viscoelastic material will be injected through the main wound between the anterior capsule and iris, until the iris is close to or touching the cornea. A curved ECP probe will be inserted through the corneal incision wound/wounds and 360° of the anterior section of the ciliary processes will be treated. The power setting will be varied according to tissue response (starting power of 250 mW with continuous setting). 'Pops' should be avoided (but recorded) but no indentation used during treatment.
Intracameral cefuroxime and dexamethasone will be injected into the anterior chamber and sutures used to close the incisions as required.
干预措施: Phacoemulsification+ Endoscopic cyclophotocoagulation (ECP) laser (Device)
Phacoemulsification alone
Cataract surgery will be performed using standard anesthesia and phacoemulsification techniques. A clear corneal incision should be used for instrumentation. The choice of viscoelastics to maintain the anterior chamber is left to the surgeon's discretion. For this study, monofocal IOLs are required.
干预措施: Phacoemulsification+ Endoscopic cyclophotocoagulation (ECP) laser (Device)
结局指标
主要结局
Change in post-washout IOP at 24 months
时间窗: Two years
Change in post-washout IOP of at least 2.7 mmHg at 24 months from baseline. The IOP will be measured using Goldmann applanation tonometer at each visit.
次要结局
- The percentage of IOP reduction(Two years)
- Change in number of glaucoma medication used(Two years)
- Cost effectiveness(Two years)
- Intra- and Post-operative complication rates(Two years)