What is a Vascular Tunic?

The Role of the Uvea in Vision: Anatomy, Conditions, and Care

A vascular tunic surrounds almost your entire eye, which is also known as the uvea. It is a three-part structure that is crucial in eye function. They assist in key functions, such as regulating important eye processes and maintaining surrounding tissues. Let us understand what a vascular tunic is, its functions, and conditions or disorders related to it.

What is a vascular tunic?

The vascular tunic, or uvea, can be found in the outer walls of your eyes. These walls are composed of three layers, with the uvea in the centre. A vascular tunic is a coating of pigment that gives essential nutrition to the delicate tissues of an eye. Some of its main functions are feeding the retina with oxygen and nutrients and controlling the quantity of light that enters the eye.

Into how many parts is a vascular tunic divided?

The vascular tunic is separated into three parts. These are the choroid, ciliary body, and iris. The choroid is the posterior uvea, whereas the iris and ciliary body make up the anterior uvea.

Functions of the Vascular Tunic

Each part of the vascular tunic, or uvea, functions differently. Here is a detailed analysis of how the iris, ciliary body, and choroid function:

• Iris : The iris is a coloured area of an eye, which controls pupil size and regulates the quantity of light that reaches the eye. This ring-shaped muscular tissue is located just under the cornea in front of your eye. To regulate the amount of light that reaches your eyes, it may automatically broaden or constrict.
• Ciliary Body : The ciliary body consists of ciliary muscles. These muscles aid your eye in focusing on things at different distances. The ciliary body is a ring of tissue behind the iris. The muscles regulate the form of your eye’s lens. This helps you focus your gaze on objects that are nearby you. This part of the uvea also creates aqueous humour fluid, which is a fluid that fills a portion of your eye and keeps it shaped like a globe.
• Choroid : The choroid, which is positioned between the retina and sclera, provides blood and oxygen to the retina and other essential components of the eye. The choroid is a thin sheet of tissue which is covered with blood vessels. Being the largest part of the vascular tunic, it covers the rearmost and central sections of a human eyeball.

The colour of the choroid is another crucial characteristic. It lowers the amount of light that bounces off your retina.

Conditions that Affect the Vascular Tunic

Several conditions and disorders might affect the uvea in your eye. Here are the conditions that might affect your vascular tunic:

• Albinism
• Coloboma
• Eye cancers like intraocular melanoma
• Choroideremia
• Uveal effusion syndrome
• Diabetes-related retinopathy
• Choroidal neovascularisation
• Ocular ischaemia, which is the lack of blood flow caused by an eye stroke
• Iris malformations such as corectopia or polycoria, which are misaligned irises and multiple pupils
• Injuries
• The wet form of macular degeneration
• Sarcoidosis
• Synechiae
• Uveitis

Symptoms of Vascular Tunic-Related Conditions

Understanding symptoms of these conditions helps you to manage them by taking preventive care. Here are the symptoms of the conditions mentioned above:

• Eye redness
• Dilated pupils or mydriasis
• Double vision or diplopia
• Eye pain
• Swollen conjunctiva
• Eye strain
• Headache
• Pinpoint pupils or eye miosis
• Loss of vision
• Change of pupil shape from a circle to an irregular one
• Teary eyes or epiphora
• Extreme pain
• Sensitive to light
• Blurred vision
• Floaters

Preventive Measures to Protect the Vascular Tunic

You may take a variety of steps to safeguard the health of your vascular tunic and your eyes in general. Follow and implement these preventive measures to keep your vascular tunic free from conditions:

• Prioritise regular eye exams, as these can detect numerous eye conditions before you experience any symptoms.
• Try to avoid excessive nicotine use, as it can affect your circulatory system.
• Use goggles and safety glasses to prevent any eye injury.
• Do not ignore any infections in your eyes. If it persists for more than a few days, it can quickly spread and become more serious.

The vascular tunica, or uvea, is exactly in the centre of everything your eye performs, both physically and symbolically. It is divided into three parts: iris, ciliary body, and choroid. However, it might be frightening to be unsure of what to anticipate when your uvea is malfunctioning. Consult a doctor or healthcare expert to prevent your uvea.