Glaucoma affects 70 Million people worldwide and is the 2nd leading cause of irreversible blindness
Glaucoma is a group of conditions with heterogeneous causes that results in damage to the optic nerve head and loss of visual field. Glaucoma is one of the most common ophthalmic conditions encountered and the World Health Organization (WHO) estimated that in 2010 glaucoma accounted for 2% of visual impairment and 8% of global blindness. Glaucoma is the second leading cause of blindness overall, with an estimated prevalence of 70 million cases worldwide.
The disease manifests as a progressive, chronic optic neuropathy with a loss of retinal ganglion cells and their axons, resulting in atrophy of the optic nerve and loss of visual function that can eventually lead to blindness. Its prevalence increases exponentially with age, but risk factors also include family history, ethnicity, central corneal thickness, myopia and increased intraocular pressure (IOP). The higher the IOP, the greater the likelihood of visual field loss, optic nerve damage and blindness. Elevated IOP is the only risk factor that can be addressed with therapies such as medications or glaucoma surgery. Managing IOP early in the disease process has been shown to delay or even arrest glaucoma progression and the resultant visual field loss.
1. Limited drainage of aqueous humour from the anterior chamber.
2. Excessively high Intraocular pressure.
3. Damage to the optic nerve.
Most patients are initially treated with topical medication, but often this option is insufficient to reach the appropriate IOP, and is not tolerated due to side effects. Furthermore, in many third world countries medications are too costly and a one-time intervention is necessary. Also, low patient compliance with medications is a serious problem in glaucoma.
Thus, frequently, surgery becomes necessary. The most common surgical procedure used in open-angle glaucoma is a trabeculectomy (also known as filtration surgery). This procedure is invasive, requires years of surgical experience and is associated with relatively high complication and failure rates as well as prolonged visual instability.
Healing and scarring are the main obstacles for long term IOP control after filtration surgery. Antimetabolites such as 5-Fluorouracil (5-FU) and Mitomycin C (MMC) are frequently used to reduce scarring and improve drainage. The use of these substances is potentially hazardous and requires high expertise to prevent overfiltration and hypotony. Therefore there is a need to widen the existing surgical options for Glaucoma.