{"id":1839,"date":"2026-10-20T08:52:52","date_gmt":"2026-10-20T08:52:52","guid":{"rendered":"https:\/\/laseristanbulclinic.com\/eye-glossary\/ocular-hypertension\/"},"modified":"2026-10-20T12:57:02","modified_gmt":"2026-10-20T12:57:02","slug":"ocular-hypertension","status":"publish","type":"page","link":"https:\/\/laseristanbulclinic.com\/en\/eye-glossary\/ocular-hypertension\/","title":{"rendered":"Ocular Hypertension: Symptoms, Causes, Treatment and Glaucoma Risk"},"content":{"rendered":"\n
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  1. Home<\/a><\/li>
  2. Knowledge centre<\/a><\/li>
  3. Eye glossary A\u2013Z<\/a><\/li>
  4. Ocular Hypertension: Symptoms, Causes, Treatment and Glaucoma Risk<\/span><\/li><\/ol><\/div>\t\t\t

    Ocular Hypertension: Symptoms, Causes, Treatment and Glaucoma Risk<\/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

    \"Illustration<\/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

    Ocular hypertension<\/strong> (noun, abbreviated OHT or OHTN)<\/em>: ocular hypertension means the pressure inside the eye (intraocular pressure, or IOP) is higher than normal, but the optic nerve looks healthy and there is no loss of vision. It happens when fluid does not drain from the eye as well as it should. It is not glaucoma, but it raises the risk of glaucoma, so it is monitored by an eye specialist such as Prof. Dr. Ahmet Sat\u0131c\u0131, who leads glaucoma care at Laser Istanbul Clinic.<\/p>\n\t\t<\/div><\/div><\/div><\/div><\/section>\n\n\n\n\n

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    Ocular hypertension: key facts<\/h2><\/div>\n\t\t\t\t\t<\/div>\n\t\t\t
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    <\/svg>What it is<\/span><\/dt>
    Eye pressure that is consistently above normal, with a healthy optic nerve and normal visual fields<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Normal eye pressure<\/span><\/dt>
    Usually considered to be between 10 and 20 mmHg (American Academy of Ophthalmology)<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Usual definition<\/span><\/dt>
    Pressure consistently above 21 mmHg without optic nerve damage or visual field loss (EyeWiki); UK guidance (NICE) uses 24 mmHg or more to decide on treatment and referral<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Symptoms<\/span><\/dt>
    Usually none; it is found at a routine eye test<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Main risk<\/span><\/dt>
    Slowly developing primary open-angle glaucoma. In the Ocular Hypertension Treatment Study (OHTS), 9.5% of untreated people had developed it at 5 years, and 45.6% of all participants after 20 years<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Main treatments<\/span><\/dt>
    Observation, prescription eye drops (usually a prostaglandin analogue) or selective laser trabeculoplasty (SLT)<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>ICD-10<\/span><\/dt>
    H40.0 (glaucoma suspect, which includes ocular hypertension); ICD-10-CM H40.05-<\/dd><\/dl><\/div>\n\t\t\t\t
    <\/svg>Specialist<\/span><\/dt>
    Ophthalmologist with glaucoma experience; at Laser Istanbul Clinic, Prof. Dr. Ahmet Sat\u0131c\u0131<\/dd><\/dl><\/div>\n\t\t\t<\/div>\n\t\t<\/div><\/div><\/div><\/section>\n\n\n\n\n
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    What is ocular hypertension, and is it the same as glaucoma?<\/h2>\n\t\t\t\t

    Ocular hypertension is a risk state, not a disease of the optic nerve. Your eye constantly makes a clear fluid called aqueous humour, and an equal amount drains away, which keeps eye pressure steady. In ocular hypertension the drainage is less efficient, so pressure builds up. Glaucoma is the condition in which pressure damages the optic nerve and vision is lost. According to the American Academy of Ophthalmology (AAO), people with ocular hypertension have a normal-looking optic nerve and no sign of vision loss, but they are at increased risk of glaucoma and are considered “glaucoma suspects”.<\/p>

    <\/th>Ocular hypertension<\/th>Glaucoma<\/th><\/tr><\/thead>
    Eye pressure<\/th>Higher than normal<\/td>Often raised, but can be in the normal range<\/td><\/tr>
    Optic nerve<\/th>Healthy<\/td>Damaged<\/td><\/tr>
    Visual field<\/th>Normal<\/td>Loss of vision in the visual field<\/td><\/tr>
    Symptoms<\/th>None<\/td>Usually none in the early stages<\/td><\/tr>
    Aim of care<\/th>Monitor, and lower pressure if the risk is high<\/td>Lower pressure to slow or stop further damage<\/td><\/tr><\/tbody><\/table><\/div>

    The NHS notes that pressure can sometimes be in the normal range and still damage the optic nerve, which is why the optic nerve, not the pressure reading alone, decides whether you have glaucoma.<\/p><\/div>\t<\/div><\/div><\/div><\/section>\n\n\n\n\n

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    Ocular hypertension causes: why does eye pressure rise?<\/h2><\/div><\/div>

    The direct cause is reduced outflow of aqueous humour. EyeWiki, the AAO’s clinical wiki, explains that fluid leaves the eye through two routes, the trabecular meshwork and the uveoscleral pathway, and that ocular hypertension occurs when resistance in these routes rises. The eye keeps producing fluid at a normal rate, so pressure goes up. Age-related changes in the trabecular meshwork contribute, which is one reason it becomes more common with age.<\/p><\/div>

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    What diseases and conditions cause ocular hypertension?<\/h3>

    Most ocular hypertension is “primary”, meaning no other disease is behind it. But doctors must first rule out secondary causes, because these need different treatment. EyeWiki lists:<\/p>

    A pressure rise can also be falsely recorded: an incorrectly calibrated tonometer, poor technique, or short-term effects such as straining, stress or breath-holding.<\/p>