R R

What Is Low Tension Glaucoma?

Low tension glaucoma, also called normal tension glaucoma, is a form of open angle glaucoma in which typical optic nerve damage and visual field loss occur despite intraocular pressure readings in the statistically normal range. The optic nerve appears cupped and thinned in a pattern similar to other glaucomas. Visual field tests show characteristic arcuate defects or nasal steps. The condition is thought to involve an optic nerve that is unusually vulnerable to pressure or blood flow problems, even when pressure values are not high by standard limits.

Link to This Resource Page

Provide a valuable resource to your clients or customers by linking to this resource page. Just place the following link on your website.

To display this...

What Is Low Tension Glaucoma?

Low tension glaucoma, also called normal tension glaucoma, is a form of open angle glaucoma in which typical optic nerve damage and visual field loss occur despite intraocular pressure readings in the statistically normal range. The optic nerve appears cupped and thinned in a pattern similar to other glaucomas. Visual field tests show characteristic arcuate defects or nasal steps. The condition is thought to involve an optic nerve that is unusually vulnerable to pressure or blood flow problems, even when pressure values are not high by standard limits.

read more about low tension glaucoma ...

Copy this HTML:

Copy HTML Copied!

Causes and Risk Factors for Low Tension Glaucoma

The exact cause is not fully understood, but vascular and structural factors are believed to make the optic nerve more fragile. Low blood pressure, vasospasm, migraine, and sleep apnea have all been linked with low tension glaucoma. Some patients have thin corneas, which leads to underestimation of true intraocular pressure on standard tests. Family history of glaucoma and certain ethnic backgrounds increase risk. In many series, a large share of diagnosed glaucoma in some Asian populations falls into the normal tension range.

Symptoms and Clinical Features

As with other open angle glaucomas, early low tension glaucoma is usually asymptomatic. Over time, patients can develop patchy peripheral field loss that progresses toward central vision if untreated. On examination, the optic disc shows cupping, rim thinning, and nerve fiber layer defects that match visual field changes. Intraocular pressure measurements typically stay below or around 21 mmHg on repeated checks. The anterior chamber angle is open on gonioscopy, and no secondary cause of pressure elevation is seen.

How Is Low Tension Glaucoma Diagnosed?

Diagnosis requires evidence of glaucomatous optic nerve damage and matching visual field loss in an eye with open angles and consistently normal pressure readings. The eye doctor performs tonometry at different times of day, gonioscopy, optic nerve imaging, and standard automated perimetry. Central corneal thickness is measured because thin corneas can lead to underestimation of true pressure. Other optic neuropathies, such as ischemic, compressive, or inflammatory conditions, are ruled out based on history, exam, and sometimes neuroimaging.

How Is Low Tension Glaucoma Managed?

Management aims to lower intraocular pressure further than baseline values and to support optic nerve health. Topical pressure lowering medications, laser trabeculoplasty, and, in some cases, filtration surgery are used even though starting pressures are not high. Systemic factors such as very low nighttime blood pressure, sleep apnea, and smoking are reviewed with the patient and relevant physicians. Regular monitoring of optic nerve structure and fields tracks progression. Treatment targets are individualized and often call for lower pressures than in similar eyes without damage.

FAQs About Low Tension Glaucoma

How can I have glaucoma if my eye pressure is normal?

Normal tension glaucoma reflects an optic nerve that is sensitive to pressure levels that most eyes tolerate. In these cases, damage occurs at pressures that fall inside the usual statistical range.

Is low tension glaucoma less serious than other glaucomas?

It can still lead to significant vision loss if not recognized and treated. The main difference is the pressure range in which damage occurs, not the potential impact on sight.

Will lowering my blood pressure help low tension glaucoma?

Very high blood pressure needs control for general health, but excessively low nighttime pressures can reduce blood flow to the optic nerve. Your eye doctor and primary doctor work together to balance these concerns.

Can low tension glaucoma be cured?

There is no cure, but careful pressure reduction and management of systemic risks often slow or stop progression. Lifelong follow up is important to protect remaining vision.