Ahmed Valve Implantation Coated With Poly Lactic -Co-glycolic Acid (PLGA) Saturated With Mitomycin-C in the Management of Adult Onset Glaucoma in Sturge Weber Syndrome

Overview

Sturge weber's syndrome is an oculcutaneous syndrome, ocular manifestations may include heamangioma in the eye lids, choroidal heamangioma, or glaucoma, the glaucoma may present at infancy and may be due to resistance to aqueous outflow through trabecular meshwork(1), it may develop later and this is due to episcleral venous raised pressure.(2-3) Glaucoma associated with Sturge weber syndrome is difficult to be treated medically with high risk of complications when treated with bleb -based surgeries. Suprachoroidal hemorrhage or detachment is a challenging complication which must be encountered. The usage of Ahmed valve in the management of glaucoma associated with Sturge weber syndrome is a bleb based procedure carries the risks of over filtration or encapsulation and decreased filtration with failure to control glaucoma. The use of Ahmed valve in the management of pediatric glaucoma associated with Sturge weber syndrome has better results as recorded by Nassiri et al. Ahmed valve implantation can have some drawbacks such as pupillary irregularity, lens opacification, or encapsulation.(4-7) Glaucoma drainage devices such as Ahmed valve, Molteno or Braeveldt valve can be used when other methods of treatment fail, they provide alternative pathway to the aqueous to be collected in a plate positioned under the conjunctiva, (8-10) Encapsulation is a major problem occurs around the end plate due to fibrous reaction and so the drainage of the aqueous is decreased , Epatein (11) attributed that to fibro vascular proliferation in the episcleral tissue .the fibrous reaction is multifactorial , it may be due to the size of the end plate, the biomaterial, design or the shape of the plate. The use of drainage devices with advanced drug delivery system can improve the success of drainage device. A double-layered porous coating for Ahmed glaucoma valves based on biodegradable poly(lactic-co-glycolic acid) (PLGA) was described by Ponnusamy et al. \[12\] to produce continuous release of antifibrotic agents \[mitomycin C (MMC) and/or 5-fluorouracil (5-FU)\] to the subconjunctival space. This release continue for about one month with decreasing fibrosis, the nanofiltration membrane could entrap the proteins passing out from the anterior chamber leading to minimal increase in aqueous resistance.(12-13)

All participants will be evaluated regarding the following: Visual acuity (VA) will be measured before and after surgery. Visual field (VF) will be assessed. Optical coherence topography (OCT) Ahmed valve coated with PLGA nanoparticles saturated with Mitomycin-C 2mg/ml. Follow up will continue for one year regarding intraocular pressure IOP, VA , VF, OCT and occurrence of complications such as erosion, extrusion, infection, encapsulation and fibrosis around the stent. Data will be collected and analyzed.