Eye diseases. The structure of the eye. Orbit (most important)

Lecture notes, cheat sheets
Free library / Directory / Lecture notes, cheat sheets

Eye diseases. The structure of the eye. Orbit (most important)

Lecture notes, cheat sheets

Table of contents (expand)

1. The structure of the eye. Orbit

The eye as an integral part of the so-called opto-vegetative (OVS) or photoenergetic (FES) system of the body is involved in the adaptation of the internal environment of the body to external conditions. The vast majority of information about the world around comes to the child through the organ of vision. The eye is in a figurative and literal sense a part of the brain, placed on the periphery.

When studying the anatomy of a child, it must be remembered that the orbit in children under the age of one year approaches a trihedral prism in shape. Later it takes the form of a truncated tetrahedral pyramid with rounded edges. The base of the pyramid faces outwards and anteriorly, the apex inwards and backwards. In newborns and children of the first year of life, the angle between the axes of the orbits is sharper, which creates the illusion of convergent strabismus. However, this imaginary strabismus gradually disappears, as the angle between the axes of the orbits increases. The upper wall of the orbit borders the cranial cavity and is formed in front by the orbital part of the frontal bone, and behind by the lesser wing of the sphenoid bone. In the outer corner of the wall, a recess for the lacrimal gland is revealed, and at the place where the upper wall passes into the inner wall, a notch (or hole) for the superior orbital vein and artery is determined. There is also a spike block through which the tendon of the superior oblique muscle is thrown. In the process of comparing the orbits in terms of age, it is revealed that in children the upper wall of the orbit is thin, there is no pronounced superciliary tubercle.

When studying the outer wall of the orbit, it is noted that it borders on the temporal cranial fossa. The orbital process of the zygomatic bone separates the orbit from the maxillary sinus, and the sphenoid bone of the inner wall separates the contents of the orbit from the ethmoid sinus. The fact that the upper wall of the orbit is simultaneously the lower wall of the frontal sinus, the lower upper wall of the maxillary sinus, and the inner side wall of the ethmoidal labyrinth, explains the relatively unhindered and rapid transition of the disease from the paranasal sinuses to the contents of the orbit and vice versa.

At the top of the orbit in the lesser wing of the sphenoid bone, a round opening for the optic nerve and ophthalmic artery is defined. The superior orbital fissure is located outside and below this opening between the large and small wings of the sphenoid bone and connects the orbit with the middle cranial fossa. All the motor branches of the cranial nerves pass through this gap, as well as the superior ophthalmic vein and the first branch of the trigeminal nerve, the ophthalmic nerve.

The inferior orbital fissure connects the orbit to the inferior temporal and pterygoid fossae. The maxillary and zygomatic nerves pass through it.

The entire orbit is lined with periosteum; in front of the bony edge of the orbit to the cartilage of the eyelids is the tarsoorbital fascia. With closed eyelids, the entrance to the orbit is closed. Tenon's capsule divides the orbit into two sections: the eyeball is located in the anterior section, and the vessels, nerves, muscles, and orbital tissue are located in the posterior section.

Author: Shilnikov L.V.

>> Forward: The structure of the soft tissues of the eye

We recommend interesting articles Section Lecture notes, cheat sheets:

▪ Logistics. Crib

▪ Social Psychology. Crib

▪ Real estate economics. Crib

See other articles Section Lecture notes, cheat sheets.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

The existence of an entropy rule for quantum entanglement has been proven 09.05.2024

Quantum mechanics continues to amaze us with its mysterious phenomena and unexpected discoveries. Recently, Bartosz Regula from the RIKEN Center for Quantum Computing and Ludovico Lamy from the University of Amsterdam presented a new discovery that concerns quantum entanglement and its relation to entropy. Quantum entanglement plays an important role in modern quantum information science and technology. However, the complexity of its structure makes understanding and managing it challenging. Regulus and Lamy's discovery shows that quantum entanglement follows an entropy rule similar to that for classical systems. This discovery opens new perspectives in the field of quantum information science and technology, deepening our understanding of quantum entanglement and its connection to thermodynamics. The results of the study indicate the possibility of reversibility of entanglement transformations, which could greatly simplify their use in various quantum technologies. Opening a new rule ... >>

Mini air conditioner Sony Reon Pocket 5 09.05.2024

Summer is a time for relaxation and travel, but often the heat can turn this time into an unbearable torment. Meet a new product from Sony - the Reon Pocket 5 mini-air conditioner, which promises to make summer more comfortable for its users. Sony has introduced a unique device - the Reon Pocket 5 mini-conditioner, which provides body cooling on hot days. With it, users can enjoy coolness anytime, anywhere by simply wearing it around their neck. This mini air conditioner is equipped with automatic adjustment of operating modes, as well as temperature and humidity sensors. Thanks to innovative technologies, Reon Pocket 5 adjusts its operation depending on the user's activity and environmental conditions. Users can easily adjust the temperature using a dedicated mobile app connected via Bluetooth. Additionally, specially designed T-shirts and shorts are available for convenience, to which a mini air conditioner can be attached. The device can oh ... >>

Energy from space for Starship 08.05.2024

Producing solar energy in space is becoming more feasible with the advent of new technologies and the development of space programs. The head of the startup Virtus Solis shared his vision of using SpaceX's Starship to create orbital power plants capable of powering the Earth. Startup Virtus Solis has unveiled an ambitious project to create orbital power plants using SpaceX's Starship. This idea could significantly change the field of solar energy production, making it more accessible and cheaper. The core of the startup's plan is to reduce the cost of launching satellites into space using Starship. This technological breakthrough is expected to make solar energy production in space more competitive with traditional energy sources. Virtual Solis plans to build large photovoltaic panels in orbit, using Starship to deliver the necessary equipment. However, one of the key challenges ... >>

Random news from the Archive

Electronic tablet instead of textbooks and notebooks 29.08.2002

The Taiwan Computer Association (TCA) has created a group to promote the spread of electronic school bags in the country - computers that should combine school textbooks, notebooks, diaries and everything else a student needs to study.

Many experts, not only in Taiwan, predict that these devices will gradually replace traditional printed books. Their advantages are not so much in their low weight (a 10-inch tablet PC weighs only a little more than 1 kg), but also in the fact that switching to them will create a new, with incomparably greater opportunities, learning environment.

In addition to the fact that several dozen textbooks with pictures can be "stored" in such a computer, teachers can centrally check the work done on them and distribute materials and homework or, using electronic boards, transmit their lectures.

"Electronic backpacks" are created on the basis of tablet computers equipped with wireless communication. One of the tasks being solved now is to increase the duration of work, since students will have to use backpacks throughout the school day.

Other interesting news:

▪ Class D amplifier with 240W output power and 0,1% distortion

▪ Panoramic attachment for digital camera

▪ Bosonic computers

▪ Repair of damaged cartilage

▪ Star farthest from Earth discovered

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ section of the site Car. Article selection

▪ article We have twice two is also four, but somehow it comes out more briskly. Popular expression

▪ article Why did Galileo observe Neptune but did not recognize it as a planet? Detailed answer

▪ article Economical sanding pad. home workshop

▪ article Stamp paint. Simple recipes and tips

▪ article Power supply for multimeter M830. Encyclopedia of radio electronics and electrical engineering

Leave your comment on this article:

All languages of this page

Home page | Library | Articles | Website map | Site Reviews