Fornix Conjunctivae: Structure, Function & Diseases

The fornix conjunctivae is a part of the human eye. It is the fold of the envelope. It is located in the depth of the eye socket.

What is the fornix conjunctivae?

The fornix conjunctivae is located in the human eye. It is the envelope fold in the eye and is located in the orbit. It forms the conjunctiva of the eye in the orbit below the eyelids. Fornix conjunktivae represents the transition between the eyelid and the eyeball. It is also called the conjunctival vault. The outlets of the lacrimal gland end at the fornix. Thus, the lacrimal fluid, which supplies and protects the eye, exits at this point of the human eye. The fluid has a cleansing function and at the same time it protects against various forms of infections of the eye. The Fornix conjunctivae is divided into the Fornix conjunctivae superior and Fornix conjunctivae inferior. The superior fornix is the superior fold and the inferior fornix is the inferior fold. The fornix conjunctivae is covered with an epithelial layer. This is multilayered and very rare. The peculiarity of the epithelial layer is that it consists of cells that are elongated and at the same time have the shape of a cylinder. Therefore, the epithelium is also called highly prismatic.

Anatomy and structure

The conjunctiva in the human eye is called the tunica conjunctiva or conjunctiva. It is of a translucent structure. The conjunctiva and consists of a multilayered epithelial layer, the lamina epithelialis, and an underlying loose connective tissue layer, the tela subconjunctiva. The conjunctiva fixes the bulb in the orbit. This is a cavity in the eyes. In addition, the conjunctiva covers the entire anterior surface of the eyeball. Above and below it forms an envelope fold. These are the fornix conjunctivae superior and fornix conjunktivae inferior. The conjunctiva then continues as the tunica conjunctiva palpebralis onto the posterior lid surface. It covers this until it reaches the lid margin. Finally, it ends at this point and firmly fuses with the lid margin. Furthermore, the excretory ducts of the lacrimal glands open in the lateral superior fornix of the conjunctiva behind the eyelid. The lacrimal gland itself lies over the lateral angle of the eyelid. It is called the lacrimal gland and has a hazelnut-sized structure. The lacrimal gland is the site of production of lacrimal fluid. This moisturizes, cleanses, nourishes, and protects the eye from infection or dehydration.

Function and tasks

The fornix conjunctivae is one of the exit sites for the ducts of the lacrimal gland. Through it, the tear fluid produced can find its way to the eye. Thus, it has an important function in supplying the eye. 10-12 exit ducts of the lacrimal gland are located directly in the fornix conjunktivae superior. Another 20-30 smaller exit sites are in its immediate vicinity. The lacrimal glands provide lacrimal fluid slowly and gradually. This causes it to be continuously distributed in the eye. The exit site of the fluid is on the nasal side. Thus, it runs along the corner of the eyelid near the nose and is evenly distributed in the eye by the support of the eyelid. The lacrimal fluid has important functions. On the one hand, it has a social and emotional function. Emotions such as sadness and grief are expressed through tears. This helps the regulation of own feelings, but also has an importance in the regulation with social contacts. Emotions such as joy, happiness or pride can also trigger a flow of tears. Apart from the psychological component, the supply of tear fluid in the eye is important for other reasons. It protects the eye from infection. The fluid supplies the eye from dehydration. The tear fluid cleanses the eye from substances that enter the eye through the air. This would not be possible without the fornix conjunktivae.

Diseases

The most common eye complaints include redness, adhesions, or watery eyes. This is unpleasant and may be associated with pain. Most often, the above symptoms are conjunctivitis. It is often triggered by viruses or bacteria. Other causes are irritants such as dry air, dust or sand. Contact lenses worn for too long can also trigger irritation. Usually it starts to itch and as the itching subsides, the condition worsens. The condition is considered contagious.However, in most cases it subsides after 10-14 days. Alternatively, it is treated with medication by the ophthalmologist. In some cases, allergic reactions occur. These can be triggered by pollen, house dust, animal hair or cosmetic products. The usual symptoms are characterized by redness and itching. Burning or watering eyes are also possible. The symptoms are often associated with a swollen nose or sneezing. Allergy testing and avoidance of irritant situations are recommended. Other problems include watery eyes for seemingly no reason. Functional disorders or anatomical disorders may be found as the cause in this case. The function of the eyelid may be disturbed due to inflammation or irritation of the eyelid. Another reason is the blockage of the lacrimal ducts. In some cases, even dry eyes are considered the cause of watery eyes. The lacrimal fluid no longer runs along the side of the nose, but exits at various points over the lower eyelid and runs downward over the cheeks following gravity. The flow of tears cannot be controlled by the sufferer.