{"id":1991,"date":"2026-10-20T08:55:00","date_gmt":"2026-10-20T08:55:00","guid":{"rendered":"https:\/\/laseristanbulclinic.com\/eye-health\/retina-glaucoma\/glaucoma-symptoms-causes-and-when-surgery-is-needed\/"},"modified":"2026-10-20T12:59:48","modified_gmt":"2026-10-20T12:59:48","slug":"glaucoma-symptoms-causes-and-when-surgery-is-needed","status":"publish","type":"page","link":"https:\/\/laseristanbulclinic.com\/en\/eye-health\/retina-glaucoma\/glaucoma-symptoms-causes-and-when-surgery-is-needed\/","title":{"rendered":"Symptoms of High Eye Pressure: Glaucoma Causes and When Surgery Is Needed"},"content":{"rendered":"\n
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  1. Home<\/a><\/li>
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  4. Symptoms of High Eye Pressure: Glaucoma Causes and When Surgery Is Needed<\/span><\/li><\/ol><\/div>\t\t\t

    Symptoms of High Eye Pressure: Glaucoma Causes and When Surgery Is Needed<\/h1>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t
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    The symptoms of high eye pressure are usually none: raised pressure inside the eye normally causes no pain or blurring until the optic nerve is already damaged, which is why glaucoma is found at eye tests, not by feel. The exception is an acute angle-closure attack, with severe eye pain, a red eye, halos, blurred vision and nausea, which is an emergency. Surgery is considered when drops and laser cannot keep the pressure low enough. Glaucoma at Laser Istanbul Clinic is led by Prof. Dr. Ahmet Sat\u0131c\u0131.<\/p><\/div>\n\t\t\t\t\t<\/div>\n\t<\/div><\/div>\n<\/section>\n\n\n\n\n

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    What are the symptoms of high eye pressure?<\/h2><\/div>\n\t\t\t\t\t<\/div>\n\t\t\t

    For most people, high eye pressure has no symptoms at all. The American Academy of Ophthalmology (AAO) says that open-angle glaucoma, the most common type, has no warning signs or obvious symptoms in the early stages, and that ocular hypertension (high eye pressure before any nerve damage) usually has no signs or symptoms either. The NHS describes chronic glaucoma in the same way: it develops slowly over years and is usually found during a routine eye test. That is why the AAO calls glaucoma the “silent thief of sight”, and why it reports that about half of the people with glaucoma do not know they have it.<\/p>\n

    What you can notice depends on the type of glaucoma and how far it has gone:<\/p>

    Situation<\/th>What you may notice<\/th>How fast<\/th>What to do<\/th><\/tr><\/thead>
    High pressure or early open-angle glaucoma<\/th>Nothing<\/td>Years<\/td>Regular eye tests: the NHS advises one at least every 2 years, and more often if you are at higher risk<\/td><\/tr>
    Advanced open-angle glaucoma<\/th>Blind spots and loss of side (peripheral) vision, sometimes blurred vision<\/td>Gradual<\/td>See an eye doctor promptly; lost vision cannot be restored<\/td><\/tr>
    Acute angle-closure attack<\/th>Severe eye pain, headache, red eye, sudden blurred vision, rainbow-coloured halos around lights, nausea or vomiting<\/td>Hours<\/td>Emergency: go to eye casualty or an emergency department now<\/td><\/tr>
    Warning episodes before a full attack<\/th>Blurred vision, halos, mild headaches or eye pain that come and go<\/td>Episodes<\/td>Get an eye examination soon; do not wait for a full attack<\/td><\/tr><\/tbody><\/table><\/div><\/div>\n\t\t\t
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    Eye pressure signs: what can you actually feel?<\/h3>

    Very little. You cannot sense eye pressure, and the AAO notes that diseases of the eye are one of the least common causes of headaches. A pressure feeling, ache or heaviness behind one eye is far more often caused by sinus congestion, tension-type headache, migraine or eye strain than by glaucoma. Do not assume that feeling normal means a normal pressure, and do not assume an aching eye means high pressure. The only way to know is to have your pressure measured, together with a look at the optic nerve.<\/p><\/div><\/div>\n\t\t\t\t

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    Can high eye pressure cause blurry vision?<\/h3>

    Sometimes, but rarely in the early stages. In slow open-angle glaucoma, blurred vision generally appears late, when the optic nerve is already damaged. In an acute angle-closure attack, pressure rises quickly and vision blurs suddenly, usually with pain, halos and nausea. If blur comes with a red, painful eye, treat it as an emergency. If your vision is simply blurry, there are many other causes, from needing new glasses to cataract, and an eye test finds them.<\/p><\/div><\/div>\n\t\t\t\t

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    Not glaucoma: flashes, floaters and a curtain across your vision<\/h3>

    A dark curtain or shadow in your vision, new floaters or flashes of light point to a different problem, a possible retinal detachment, which the NHS says needs urgent help. Retina surgery: vitrectomy & retinal detachment \u2192<\/a><\/p><\/div><\/div>\n\t\t\t<\/div>\n\t\t<\/div><\/div><\/div><\/section>\n\n\n\n\n

    What is eye pressure, and what is considered dangerously high eye pressure?<\/h2><\/div>

    Eye pressure, or intraocular pressure (IOP), is the pressure of the fluid inside the front of your eye. The eye makes a clear fluid (aqueous humour) all the time, and it drains out through a sieve-like channel at the edge of the cornea. When production and drainage balance, the pressure stays steady. It is measured in millimetres of mercury (mmHg), the same unit as blood pressure, although the two are separate measurements.<\/p>\n

    The usual range in the population is about 10 to 21 mmHg<\/strong>, with an average of about 15 mmHg in healthy adults, according to a 2023 study in Cureus<\/em>; the AAO gives about 10 to 20 mmHg. Pressure is not a fixed number:<\/p>\n