{"id":1828,"date":"2026-10-20T08:52:20","date_gmt":"2026-10-20T08:52:20","guid":{"rendered":"https:\/\/laseristanbulclinic.com\/eye-glossary\/glaucoma\/"},"modified":"2026-10-20T12:56:51","modified_gmt":"2026-10-20T12:56:51","slug":"glaucoma","status":"publish","type":"page","link":"https:\/\/laseristanbulclinic.com\/en\/eye-glossary\/glaucoma\/","title":{"rendered":"Glaucoma: What It Is, Types, Symptoms, Causes and Treatment"},"content":{"rendered":"\n
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  1. Home<\/a><\/li>
  2. Knowledge centre<\/a><\/li>
  3. Eye glossary A\u2013Z<\/a><\/li>
  4. Glaucoma: What It Is, Types, Symptoms, Causes and Treatment<\/span><\/li><\/ol><\/div>\t\t\t

    Glaucoma: What It Is, Types, Symptoms, Causes and Treatment<\/h1>\n\t\t\t\t\t\t

    Medically reviewed by {{surgeon}}<\/span><\/strong>, {{surgeon’s title and specialty}}<\/span>, on {{review date}}<\/span>. Last updated {{date}}<\/span>.<\/p>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t

    \"Eye<\/figure><\/div>\n\t\t\t<\/div><\/div>\n<\/section>\n\n\n\n\n
    \n\t\t<\/svg>Definition<\/span>\n\t\t\t

    Glaucoma<\/strong> (noun)<\/em>: glaucoma is a group of eye diseases that damage the optic nerve, the cable that carries images from the eye to the brain. In most cases the damage is linked to pressure inside the eye that is too high for that nerve to tolerate, and it usually causes no pain or early warning signs. Glaucoma damage is permanent, but treatment that lowers eye pressure can slow or stop further loss, which is why early detection matters. At Laser Istanbul Clinic, glaucoma is led by Prof. Dr. Ahmet Sat\u0131c\u0131.<\/p>\n\t\t<\/div><\/div><\/div><\/div><\/section>\n\n\n\n\n

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    Glaucoma: key facts<\/h2><\/div>\n\t\t\t\t\t<\/div>\n\t\t\t
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    <\/svg>What is damaged<\/span><\/dt>
    The optic nerve at the back of the eye<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Main driver<\/span><\/dt>
    Eye pressure (intraocular pressure) that is too high for that eye; the normal range is typically about 10 to 20 mmHg, but glaucoma can also occur at normal pressure<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Main types<\/span><\/dt>
    Open-angle (the most common), angle-closure, normal-tension, secondary and childhood (congenital) glaucoma<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Early symptoms<\/span><\/dt>
    Usually none. Side (peripheral) vision is lost first, slowly<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Emergency form<\/span><\/dt>
    Acute angle-closure: sudden severe eye pain, blurred vision, headache, nausea, rainbow-coloured halos around lights<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Reversible?<\/span><\/dt>
    No. Vision already lost cannot be restored, but treatment can protect the sight you still have<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>How common<\/span><\/dt>
    An estimated 7.7 million people worldwide had distance vision impairment or blindness due to glaucoma in 2020 (WHO); around half of people with glaucoma do not know they have it (AAO, NEI)<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Who treats it<\/span><\/dt>
    An ophthalmologist; at Laser Istanbul Clinic, Prof. Dr. Ahmet Sat\u0131c\u0131, with Do\u00e7. Dr. Muhammet Derda \u00d6zer when glaucoma goes together with uveitis, retinal or corneal disease<\/dd><\/dl><\/div>\n\t\t\t<\/div>\n\t\t<\/div><\/div><\/div><\/section>\n\n\n\n\n
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    \"Illustration<\/div><\/div>\n\t\t
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    What is glaucoma?<\/h2>\n\t\t\t\t\t\t\t\t

    Glaucoma is not one disease but a family of conditions that all end in the same way: gradual damage to the optic nerve. The nerve is made of a huge number of tiny fibres that send what the retina sees to the brain, and glaucoma destroys them slowly, starting at the edges of your vision. Because the brain fills in the gaps, most people do not notice anything until a large part of their side vision has gone.<\/p>\n

    The National Eye Institute (NEI) describes glaucoma as a group of eye diseases that can cause vision loss and blindness by damaging the optic nerve. The American Academy of Ophthalmology (AAO) calls it a leading cause of blindness in people over 60 and stresses that the damage is permanent, which is why glaucoma is often called “the silent thief of sight”.<\/p><\/div>\n\t\t\t\t\t\t\t\t\t\t\t<\/div>\n<\/div><\/div><\/div><\/div><\/div><\/section>\n\n\n\n\n

    What causes glaucoma?<\/h2><\/div>

    Glaucoma is usually caused by fluid that cannot drain properly from the front of the eye. The inside of the eye makes a clear fluid (aqueous humour) all the time, and it leaves through a drainage angle where the cornea and the iris meet. When that drainage is too slow or blocked, the fluid builds up and the pressure inside the eye rises. Over months or years, that pressure damages the optic nerve.<\/p>\n

    Pressure is not the whole story. Some people develop glaucoma with normal eye pressure, which is why a pressure reading alone never decides the diagnosis.<\/p>\n

    Who is at higher risk of glaucoma?<\/h3>\n

    According to the AAO, you are at higher risk if you:<\/p>\n