The structure of our eyes
The eye is a 22-24mm diameter twin organ located in the orbit behind the protective eyelid. Its shape is defined by the sclera and the cornea.
The sclera is a strong, fibrous, white coloured tissue which may be seen through the conjuctiva which contains many tiny capillaries.
The cornea has 5 layers, is transparent and has a diameter of 0.8-0.9 mm. In the center - which is where most of surgery takes place - the thickness is 0.5-0.6 mmm.
The space between the back of the cornea and the iris is called the anterior chamber. This chamber of the eye forms as a space develops between the lens and its' closely associated iridopupillary membrane and the cornea. The posterior chamber can be found behind the iris and the lens.
Both chambers are filled with vitreous humour which plays a key role in providing oxygen and nutritive materials to the inner eye tissue. They also create an internal pressure, similar to a suction. The lens, iris and it's opening can be found behind the pupil. The lens changes shape and location to enable us to focus on near and far objects.
The largest part of the eye is the transparent tissue found behind the lens called the vitreous body.
The retina lines the back of the eye; its thickness is app. 0.1-0.4mm. The ten layers of the retinal tissue are responsible for receiving optical information and then through the optical nerve the stimulus is transmitted to the brain.
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