1.Why should we pay attention to optic nerve disease?
The optic nerve consists of the axons of the retinal ganglion cells. The axons of the optic nerve are sheathed once they leave the scleral sieve plate, and the optic nerve is surrounded by three layers of meninges that connect to the meninges inside the skull. The optic nerve is part of the central nervous system and when damaged or invaded, its nerve cells cannot regenerate and can lead to permanent dysfunction. Therefore, the optic nerve disease must be given sufficient attention and active preventive and curative measures should be taken.
2.How to examine the optic nerve disease?
Optic nerve diseases include diseases of the optic nerve segment from the optic disc to before the optic cross. Therefore, the diagnosis of optic nerve disease must be based on medical history, visual acuity, visual field, pupil, dark adaptation, color vision and other examinations, and with the help of visual evoked potentials, fluorescein angiography, orbital and cranial X-ray, CT, ultrasound, MRI and other detection means. Among them, visual field is the most important for localization and diagnosis.
3.Which optic nerve diseases are the elderly susceptible to?
There are three common causes of optic nerve diseases: inflammation, vascular diseases and tumors. Middle-aged and elderly patients should first consider vascular diseases, mainly ischemic optic nerve papillopathy, optic nerve atrophy, etc.
4.What is anterior ischemic optic neuropathy?
Anterior ischemic optic neuropathy is a group of syndromes characterized by sudden vision loss, optic disc edema and characteristic visual field loss due to ischemia of the small branches of the posterior ciliary vessels supplying the sieve plate area and sieve plate area of the optic disc, resulting in local infarction of the supply area.
5.What causes anterior ischemic optic neuropathy?
Causes of anterior ischemic optic neuropathy include: local vascular lesions of the optic disc, such as inflammation, arteriosclerosis or embolism. Increased blood viscosity, such as erythrocytosis, leukemia, etc. Ocular or systemic hypotension, such as carotid or ophthalmic artery stenosis, acute hemorrhage. Increased intraocular pressure.
6.What are the manifestations of anterior ischemic optic neuropathy?
Patients have sudden onset of painless, non-progressive vision loss that starts in one eye and can involve the other eye in a few weeks to a few years. The age of onset is more than 50 years old.
7.How to diagnose anterior ischemic optic neuropathy?
On fundus examination, the optic disc is mildly swollen and light red in the early stage, with dilated capillaries on the surface, mostly limited gray-white edema, and linear hemorrhage around the disc in the corresponding area, and visual field ischemia in the later stage. This disease is most often seen in small optic discs and those without obvious optic cups, and examination of the contralateral eye also helps in the diagnosis.
The visual field defect is often a bow-shaped or fan-shaped dark spot connected to a physiological blind spot. It corresponds to the site of alteration of the optic disc. In temporal arteritis, cords may be palpable and painful, often without pulsation, and central retinal artery obstruction or cerebral nerve palsy may also occur.
There are two clinical categories: non-arteritic and arteritic. Non-arteritis, also known as atherosclerotic, is most often seen in patients aged 40 to 60 years and may have risk factors such as diabetes mellitus, hypertension, and hyperlipidemia. Relative nocturnal hypotension may play a role in the onset, especially in patients taking antihypertensive medications. 25% to 40% of the contralateral eyes also develop. Arteritis is less common than the former, mainly ischemic optic neuropathy due to temporal arteritis, and is more common in 70- to 80-year-olds. Its vision loss and optic disc edema are more pronounced than the former, and it can develop in both eyes simultaneously. If giant cell arteritis is suspected from symptoms, signs or blood sedimentation, temporal artery biopsy should be done to confirm the diagnosis.
8.How to treat anterior ischemic optic neuropathy?
Firstly, treat the systemic disease and actively treat the primary disease. Systemic application of glucocorticoids to relieve edema and exudation due to circulatory disorders is especially important for arteritis. They can be used in high doses to prevent attacks in the other eye. Intravenous vasodilators to improve microcirculation. Oral acetazolamide to lower intraocular pressure to relatively increase ocular perfusion pressure.
9.What is optic nerve atrophy?
Optic nerve atrophy refers to axonal degeneration caused by any disease that causes lesions in the retinal ganglion cells and their axons. Optic nerve atrophy is a degenerative change of the optic nerve fibers caused by various reasons. It is characterized by pallor of the optic nerve papillae and their superficial depression. The main causes of optic nerve atrophy are the following.
(1) Inflammation and other ophthalmic diseases. Such as optic nerve papillary edema, optic nerve papillitis, retinal chorioretinitis, retinitis pigmentosa, high myopia, central retinal artery obstruction, glaucoma and intraorbital inflammation, tumors, etc. can cause optic nerve atrophy.
(2) Systemic diseases cause optic nerve atrophy. Such as hypertension, arteriosclerosis, diabetes, hyperthyroidism, leukemia, severe anemia, hemorrhage, meningitis, encephalitis, arachnoiditis of the optic cross, syphilis, tuberculosis, brain tumors, etc.
(3) Other causes of optic nerve atrophy. There are ocular trauma, orbital trauma, craniocerebral injury, intraorbital parasites, intracerebral parasites, febrile infections, drug poisoning such as quinine poisoning, harmful gas poisoning such as carbon monoxide poisoning, tobacco and alcohol poisoning, etc. In addition, local or systemic nutritional disorders or vitamin deficiency can also cause optic nerve atrophy.
10.What are the clinical manifestations of optic nerve atrophy?
Patients can feel a significant loss of visual acuity, and can also have color vision disorder and night blindness, and can be progressive until blindness. However, the sudden loss of vision and then optic nerve atrophy can be caused by trauma and acute optic neuritis. The visual field changes appear at the same time as the vision loss, mostly starting from the temporal side, usually with centripetal contraction, sometimes with fan-shaped defects and eccentric blindness, and also with central dark spots. The visual field defects are first red and green in color and then white in color. In severe cases, the pupil is dilated or the reflex to light is blunted to the point of disappearance.
11.What are the manifestations of optic nerve atrophy by fundoscopy?
Fundoscopic examination varies depending on the cause and location of the disease, and may include the following conditions.
(1) If the lesion is caused by trauma, spinal consumption, retrobulbar optic neuritis, intraorbital inflammation or tumor compression, the optic nerve papilla is pale, with clear borders and often shallow depression. In late stages, gray spots of the sieve plate and slightly thinning retinal vessels are seen. If only the macular fiber bundle of the optic nerve papilla is damaged, the temporal side of the optic nerve papilla is pale.
(2) If the lesion is caused by edema or inflammation of the optic nerve papilla, the optic nerve papilla is grayish with indistinct borders, and the sieve plate is invisible because the surface of the optic nerve papilla is obscured by mechanized exudate. At the same time, there is a white sheath next to the vessels surrounding the optic nerve papilla, and the retinal arterioles become thin. If increased intraocular pressure can cause optic nerve papilla atrophy, there is an obvious cup-shaped depression and the sieve plate is clearly visible.
(3) lesions caused by retinal chorioretinitis, retinitis pigmentosa, etc., the optic nerve papillae are waxy yellow atrophy, slightly blurred at the edges, and the retinal vessels are extremely thin.
12.How to treat optic nerve atrophy?
The main treatment of optic nerve atrophy is to control the cause of optic nerve atrophy. Vitamin drugs such as vitamin B1, vitamin B12, vitamin C, vitamin E, niacin and other vasodilators such as adenosine triphosphate, iodine preparations, stilbene, herbs, etc. are taken. In addition, oxygen therapy, tissue therapy, new needle therapy and small amount of multiple blood transfusion therapy are effective.