Case Playback:
The day of the new semester, there's a little girl high spirits of the new classrooms being walked, suddenly approached a man behind him with both hands to his eyes Wushang, it was a small meet Xu Jiumei partners mouth is also not live laugh giggle Zizi said: "Guess you know who I am?" is cover their little girl was like entering a cloud, not the cute young girl on a word, the paralysis sitting collapsed on the ground, full of thought play with girls teased her, his hands still tightly clutching his poor little girl's eyes. And other small partners, go past the flowering season when the girl God has no breathing ......
1, the normal anatomy of eye structure
The eyes are the human visual organ, in the organizational structure and physiological function have a certain degree of particularity. The outer wall of the eye by a three-capsule structure, the outer layer of fibrous membrane (cornea and sclera have the points, the cornea is rich in nerve endings, sensory sensitivity; scleral surface of the dura mater back-end connected to the optic nerve), the middle vascular membrane ( rich in blood vessels and pigments, can be divided into choroid, ciliary body and iris of three parts), inner layer of the retina (retinal from the three cells. outermost layer of photosensitive thin film. the middle layer of bipolar cell layer. innermost layer of ganglion cell layer). Inside the eye for aqueous humor, lens and vitreous, are colorless and transparent gel-like liquid, the focus of the refractive index unit. At the bottom of the eye near the bridge of the nose on both sides of the site, there are connected to the optic nerve and brain.
Second, the human eye is a fragile organ
1, the eye are so fragile, slightly violent enough to eyeball rupture.
2, eyeball by the blunt force to combat or a blunt object from the eye's surface Scratch and before, the outer layer of the cornea can cause the eye or broken off. Combined cornea is rich in nerve endings, so that stimulation of corneal foreign bodies in the outside world is extremely sensitive to even minor stimuli would give rise to a strong physiological response. Cornea after injury, cause eye pain, photophobia of eyes, the eyelids can not be opened, depending on the function of serious obstacles.
3, subject to external pressure, or swelling of the eye pressure, reflex heart rate to rise, energy reduced, blood pressure significantly decreased, thus leading to limb weakness, decreased responsiveness and adaptability. At the same time can also cause prolonged reflex breath to inhale an abrupt end. May even cause heart failure and respiratory arrest may cause death.
3, eye - cardiac reflex
Oppression of the eye, causing heart rate, blood vessel expansion. This reflection begins with the eyes of the sensory nerve endings (receptors), as amended through the eyes of the trigeminal nerve (afferent) Incoming brainstem (central), confined to the trigeminal nerve sensory nucleus, and then through the heart - vascular centers, and excited about the vagus nerve dorsal nucleus and inhibit the spinal cord lateral horn, the final adoption of the vagus nerve and sympathetic (efferent) caused by heart and blood vessels (effectors) effect.
Commonly known as the vagus nerve stress disorder: vagus nerve tension was significantly higher, prone to fainting or even cardiac arrest. Black for the immediate symptoms, dizziness, nausea and even vomiting, see the pulse of the slow decline, blood pressure lowering, or even reflex cardiac arrest
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment