Vitreous Humour: Anatomy, Function, and Related Eye Problems

Published on April 12th, 2024

Updated on April 23rd, 2025

The vitreous humour, also known as vitreous fluid, is a clear, gel substance that fills most of the space of the eye, from the lens down to the retina. The vitreous humour is the largest part of the eyeball and its functions include maintaining the shape of the eye, maintaining oxygen gradient, shock absorption and vision clarity. Eye conditions related to the vitreous humour include eye floaters, vitreous degeneration and posterior vitreous detachment. Ways to take care of the vitreous humour include booking regular eye tests, eating a healthy diet, exercising regularly and stopping smoking. Keep reading to learn more about the structure of the vitreous humour and its functions.

What is the Vitreous Humour of the Eye?

The vitreous humour of the eye is a gel-like substance that fills the inside of the eyeball, according to the National Cancer Institute. The vitreous humour is a clear substance comprising mostly water; the rest is made up of salts, sugars, collagen and proteins. According to an article published in the National Library of Medicine titled, Vitreous function and intervention of it with vitrectomy and other modalities, the vitreous humour is the largest intraocular component and plays an important role in the eye’s development and oxygen metabolism.

Are the Vitreous Body and the Vitreous Humour the Same?

Yes, the vitreous body and the vitreous humour are the same thing, they are simply different terms for this part of the eye’s anatomy.

What is the Structure of the Vitreous Humour?

The vitreous humour provides the shape of the eyeball and is made of mostly water with other substances such as collagen and glucose. Collagen provides the vitreous humour with strength and also maintains its gel state. According to the National Library of Medicine, the vitreous humour makes up 80% of the intraocular volume.

A diagram of the vitreous humour inside the eyeball.

What is the Vitreous Humour Made of?

The vitreous humour is made of approximately 98-99% water, according to an article published in Science Direct. The rest is comprised of trace amounts of collagen, ions, hyaluronic acid, glucose, anions and cations.

What Colour is the Vitreous Humour?

The vitreous humour is transparent or clear and, therefore, is colourless. The vitreous humour is clear as it is made up almost completely of water and does not contain any substances that would give it colour.

Where is the Vitreous Humour Located?

The vitreous humour is located between a person’s lens and retina, in the vitreous cavity, according to the Cleveland Clinic. In the vitreous cavity, the vitreous humour is located in a protective layer called the vitreous membrane. According to an article published in the National Library of Medicine, the vitreous humour is adjacent to the ciliary body, retina and lens.

What is the Function of the Vitreous Humour in the Eye?

There are four main functions of the vitreous humour according to Medical News Today, which are maintaining the shape of the eye, maintaining oxygen gradient, shock absorption and vision clarity. The vitreous humour maintains the shape of the eye, making up 80% of the eye’s volume and holding the retina and lens in place. According to Medical News Today, the vitreous humour ensures that the eye maintains proper oxygen balance so that there is a lower oxygen concentration near the lens and a higher concentration near the retina. Vitreous humour helps with shock absorption to prevent injuries as it is a viscous and soft fluid. Finally, vision clarity is a function of the vitreous humour due to its clear nature, allowing light to travel unobstructed to the retina.

How Does the Vitreous Humour Help the Human Eye See?

The vitreous humour helps the human eye see by helping with vision clarity as it lets light in to hit the retina. As the vitreous humour is a clear substance, it does not provide any obstruction when light enters the eye. The aqueous humour on the other hand, helps the eye maintain optimal inflation and its shape by providing nutrients.

Is the Vitreous Humour Sensitive to Light?

No, the vitreous humour is not sensitive to light, the retina is the light-sensitive layer in the eye. The retina is located at the back of the eye and converts light that enters the eye into electrical impulses which the optic nerve then sends to the brain.

What are the Vitreous Humour-related Eye Problems?

The vitreous humour-related eye problems include eye floaters, posterior vitreous detachment, vitreous hemorrhage, vitreous degeneration and persistent hyperplastic primary vitreous. These eye conditions and their definitions are listed below.

Eye floaters: Eye floaters are an eye problem where a person sees spots or lines in their vision caused by changes to the vitreous inside the eye.
Posterior vitreous detachment: Posterior vitreous detachment is an eye condition that is characterised by the vitreous humour separating from the retina often due to the natural ageing process.
Vitreous hemorrhage: A vitreous hemorrhage occurs when there is blood in the vitreous cavity. The causes of bleeding in the vitreous are abnormal vessels, normal vessels and extension of blood from an adjacent source.
Vitreous degeneration: Vitreous degeneration occurs when the vitreous begins to shrink and liquefy, most commonly due to age.
Persistent hyperplastic primary vitreous: Persistent hyperplastic primary vitreous (PHPV) causes a failure of the embryological, primary vitreous and hyaloid vasculature to regress.

1. Eye Floaters

Eye floaters are an eye problem where a person sees spots or lines in their vision caused by changes to the vitreous inside the eye. Eye floaters can look like lines, strings, cobwebs, threadlike stands and black or grey dots. The causes of eye floaters include diabetic retinopathy, ageing, eye injuries, migraines and retinal detachment. Eye floaters can be treated through eye surgery and laser therapy, or simply waiting out the symptoms in some cases, as symptoms may lessen over time and become tolerable. Your optometrist will advise which treatment is best.

A person’s vision affected by eye floaters.

2. Posterior Vitreous Detachment

Posterior vitreous detachment is an eye condition that is characterised by the vitreous humour separating from the retina often due to the natural ageing process. Symptoms of posterior vitreous detachment include eye floaters and flashes of light, according to the Cleveland Clinic. Posterior vitreous detachment is unlikely to cause vision loss and should not cause any pain. As posterior vitreous detachment is non-sight threatening, treatment is not always necessary, however, treatment may be advised if there are complications such as a retinal tear, retinal detachment, macular pucker and macular hole.

3. Vitreous Hemorrhage

A vitreous hemorrhage occurs when there is blood in the vitreous cavity. The three causes of bleeding in the vitreous are abnormal vessels which are prone to bleeding, normal vessels which rupture due to stress and extension of blood from an adjacent source such as tumours, according to the American Academy of Ophthalmology. The symptoms of a vitreous hemorrhage include eye floaters and more severe cases may cause issues with a person’s visual acuity and visual field. Treatment for a vitreous hemorrhage is determined by treating the underlying cause.

4. Vitreous Degeneration

Vitreous degeneration occurs when the vitreous begins to shrink and liquefy, most commonly due to age, according to the Kellogg Eye Centre. Vitreous degeneration causes symptoms such as eye floaters and posterior vitreous detachment as the vitreous separates from the retina. While the most common cause of vitreous degeneration is age, this condition can be accelerated due to previous cataract surgery, eye trauma and myopia (nearsightedness). Treatment is not typically necessary for vitreous degeneration as most instances will not affect a person’s vision other than eye floaters which people can get used to over time.

5. Persistent Hyperplastic Primary Vitreous

Persistent hyperplastic primary vitreous (PHPV), more commonly known as persistent fetal vasculature, is a congenital condition present at birth that causes a failure of the embryological, primary vitreous and hyaloid vasculature to regress, according to an article published in the National Library of Medicine by M Silbert and AS Gurwood. There are three presentations of PHPV which are a purely anterior presentation, a purely posterior presentation and, the most common clinical presentation, which is a combination of anterior and posterior presentations.

What are the Different Ways to Take Care of the Vitreous Humour?

The different ways to take care of the vitreous humour according to the Cleveland Clinic include booking regular eye tests, eating a healthy diet, exercising regularly and stopping smoking. These ways to take care of the vitreous humour are listed below.

Book regular eye exams: Booking regular eye exams is very important in taking care of your overall eye health, including the health of your vitreous humour. Eye exams allow optometrists to monitor the health of your eyes and detect eye problems.
Eat a healthy diet: A healthy and balanced diet is beneficial for overall eye health including for the vitreous humour. By eating well, you give your body the fuel it needs which helps to boost immunity and health.
Exercise regularly: Regular exercise is beneficial for eye health as it lowers the chance of developing conditions that may affect a person’s eyes such as diabetes or high blood pressure.
Stop smoking: Smoking is very detrimental to a person’s eye health as it has been shown to cause damage to the macula and the retina. Smoking is also linked to an increased risk of age-related macular degeneration.

What is the Importance of a Regular Eye Exam for the Vitreous Humour?

A regular eye test is very important as it can detect issues with the vitreous humour such as a posterior vitreous detachment and vitreous degeneration. We recommend everyone has an eye test at least once every two years or, if you are over the age of 65, then a year review is advised. If you are experiencing any noticeable changes in your vision, you also should contact an optometrist so they can assess your vision and eye health.

A patient having an eye exam to take care of their overall eye health and vitreous humour.

How can Oscar Wylee Help Take Care of Your Eyes?

Oscar Wylee can help you take care of your eyes by providing high-quality eye tests performed by skilled optometrists. Our Oscar Wylee optometrists use modern equipment to assess your eye health and vision to detect any signs of eye disease and provide treatment, or refer patients where necessary. After your eye test, you can browse our wide range of frames and order your new glasses on the same day.

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