The Ex-PRESS mini shunt versus Trabeculectomy In African Patients: a Randomized controlled clinical trialclinical
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Open angle glaucoma is a characteristic optic neuropathy resulting in progressive visual field loss. Raised intraocular pressure (IOP) is an important risk factor for the development of the disease.

Glaucoma filtration surgery is indicated when glaucomatous damage progresses. The surgery can be either a trabeculectomy or by insertion of a glaucoma drainage device. Trabeculectomy with Mitomycin C has been used worldwide as the surgery of choice, and has been proven to be beneficial in lowering IOP in black Africans. However, it is associated with many post operative complications.

The Ex-PRESSTM Mini Shunt is a miniature non-valved stainless steel device which when implanted under the scleral flap, diverts aqueous humour from the anterior chamber to the subscleral space. Insertion of the Ex-PRESSTM Mini Shunt  has been shown to reduce intraoperative time, reduce the risk of bleeding and lessen post-operative inflammation.

Rationale:     There are very few published studies on prospective randomized studies comparing the Ex-PRESSTM Mini Shunt and trabeculectomy. Furthermore, no such study has been done in exclusively an African population. It would be beneficial to the patient if implantation of the Ex-PRESSTM Mini Shunt is proven to be  associated with less post operative inflammation and complications in our population.

Objective:     To compare the efficacy and safety of Ex-PRESSTM Mini Shunt to standard trabeculectomy in black East African patients with open angle glaucoma.

Methodology: It will be a single centre randomized controlled trial. The study population will be all patients diagnosed with open angle glaucoma attending the Glaucoma Clinic at the Kenyatta National Hospital. The primary outcome Measure will be mean IOP at 12 months compared between the treatment groups. Secondary outcome measures will be surgical complications in each treatment group, comparison of the proportion of patients achieving success or failure, need for additional laser, change in visual acuity, change in mean number of glaucoma medications and difference bleb appearance between the two procedures over time. The sample size 60 patients, 30 in each arm. SAS Version 9.2 will be used to analyze the data.

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