optic neuritis
Introduction
Introduction to optic neuritis Optic neuritis (ON) refers to the inflammation of the optic nerve, the intraocular canal, and the intracranial optic nerve that occur after the sclera. Since the lesion is caused by the optic nerve in the posterior segment of the eyeball, and there is no change in the fundus, the disease is named retrobulbarneuritis, and it is divided into acute retrobulbar optic neuritis according to the urgency of optic nerve inflammation. Chronic retrobulbar optic neuritis. In recent years, foreign literature has been collectively referred to as optic neuritis. basic knowledge The proportion of illness: 0.05-0.1% Susceptible people: no specific population Mode of infection: non-infectious Complications: multiple sclerosis optic atrophy
Cause
Cause of optic neuritis
1, drugs can cause optic nerve damage
Ethambutol is a synthetic anti-tuberculosis drug. About 2% of patients with long-term use of ethambutol can cause optic nerve damage, especially in patients who use more than 25mg/kg per day. Leibold reports that 59 patients use ethylamine. Butanol treatment, the daily dose of 35mg / kg, the incidence of optic nerve damage is about 18%, and the daily 25mg / kg is 2.25%, so it is currently considered safer 15mg / kg per day, optic nerve damage is more than damage to the nipple macular bundle Axonal optic neuritis, visual loss, central dark spot and color vision disorder, a small number of patients with optic nerve fasciitis, causing narrowing of the surrounding visual field, but also due to visual cross-interference caused by temporal hemiparesis, ethambutol The optic nerve damage is often reversible. After weeks or months after stopping the drug, the visual acuity can be gradually restored. When the visual acuity is restored, the patient who continues to take ethambutol but has no recurrence of optic neuritis.
In addition, isoniazid, streptomycin, chloramphenicol, chloroquine, digitalis, chlorpropamide, iodochlorhydroxyquin, oral contraceptives and organic insecticides all cause optic nerve damage. Report.
2, infectious diseases
Can cause optic neuritis, especially in patients with debilitation and malnutrition, such as mumps, chickenpox, flu, etc. can cause viral infection (postviral optic neuritis), typhoid fever, infectious mononucleosis, acute dissemination Encephalomyelitis, meningitis, herpes zoster, Guillain-Barre syndrome, etc. can also cause optic neuritis, such as tonsillitis and dental caries.
Because the optic nerve is closely adjacent to the posterior sinus and the bone wall of some sinuses is extremely thin, it has been thought in the past that inflammation of the posterior sinus (such as the sphenoid sinus, posterior ethmoid sinus) can cause optic neuritis, and some patients undergo sinus surgery. After the treatment, optic nerve inflammation also supports this hypothesis. However, according to a large number of case-tracking observations in recent years, many original diagnoses were caused by sinusitis caused by optic neuritis, which was later confirmed as multiple sclerosis. It is generally believed that the possibility of sinusitis causing optic neuritis is minimal.
3, intraocular infection
Intraocular inflammation is common in retinal choroiditis, uveitis and sympathetic ophthalmia, which can spread to the optic disc, causing intraocular optic neuritis, and periostitis can directly spread to cause posterior optic neuritis.
4, systemic diseases
Such as syphilis, tuberculosis, sarcoidosis, coccidioidomycosis, cryptococcosis and bacterial endocarditis can also cause optic neuritis, especially syphilis is the most common, syphilis can cause a variety of eye diseases, but the most common and most Severe is optic neuritis and optic atrophy, it can occur in congenital syphilis or acquired syphilis, especially in patients with spinal cord paralysis and paralytic dementia.
5, vascular disease
Often caused by optic nerve damage, ischemia in the anterior region of the optic nerve sieve can cause anterior ischemic optic neuropathy, while ischemia in the posterior region of the optic nerve sieve plate causes posterior ischemic optic neuropathy (posterior ischemic optic neuropathy) Blood optic neuropathy is more common in middle-aged and elderly people, with acute visual impairment associated with a large central dark spot, but normal fundus, decreased central blood pressure in the central retina, and fundus fluorescein angiography may indicate prolonged arm-retinal circulation.
Intracranial arteritis (or giant cell arteritis) can also cause optic nerve damage. The patient's visual impairment is accompanied by damage to the intracranial arteries, especially the superficial temporal artery, which is characterized by hardening and tenderness of the superficial temporal artery. Increased viscosity, accelerated erythrocyte sedimentation rate, in addition, nodular polyarteritis and no pulse disease can also cause optic nerve damage.
6, metabolic diseases
It is also the cause of optic nerve damage. Optic neuritis can occur in diabetes, thyroid dysfunction and breastfeeding. The optic neuritis caused by breastfeeding is special, called lactation optic neuritis. This disease occurs in lactating women. The mechanism is unclear. After stopping breastfeeding and treating with vitamin B and corticosteroids, the visual function can return to normal.
7, tumor
Including leukemia and malignant lymphoma, which can directly infiltrate or oppress to cause optic nerve damage, clinical manifestations of visual impairment and visual field defects of carcinomatic optic neuropathy (carcinomatous optic neuropathy), patients with multiple original cancer, but the tumor has been static for many years, sudden monocular Or binocular vision disorder with visual field damage, but the fundus is normal, because the lesions are mostly sleeve-shaped damage to the optic nerve, so radiological examination is often difficult to find lesions, usually lung cancer and breast cancer are more likely to cause cancerous optic neuropathy.
Prevention
Optic neuritis prevention
1, usually should avoid tobacco, alcohol, spicy, spicy, fried food. You should choose some light, digestible, and nutritious foods in your life.
2, appropriate activities to enhance resistance, but also to ensure adequate sleep. Should pay attention to work and rest, life should be regular, to actively exercise the body to enhance physical fitness and prevent colds.
Complication
Optic neuritis complications Complications multiple sclerosis optic atrophy
Multiple sclerosis can occur concurrently, leading to optic atrophy and even blindness in the advanced stage.
Symptom
Optic neuropathy symptoms common symptoms visual impairment eyeball tenderness light reflex disappears spontaneous intrabulbar hemorrhage morning and lower eyelid adhesion blind spot
1, vision loss
Most of the vision drops suddenly, and even after a few days of illness, it can be reduced to light or no light.
2, eyeball
When the eyeball rotates, the back of the eyeball is pulled like a pain, and the deep part of the eye is tender.
3, pupil
The pupil is slow or absent from light reflection, or does not respond to light.
4, the fundus
When changing papillitis, visual papillary congestion, mild elevation (below 3D), unclear margin, disappearance of physiological depression, retinal vein filling and distortion, retinal edema around the papilla, flaming hemorrhage and yellow-white exudation, sometimes affecting the macula The department causes radial edema and wrinkles in the macula. In the posterior optic neuritis, the early fundus is basically normal, the color of the late optic papilla is lightened, and the optic nerve is atrophied.
Examine
Optic neuritis examination
Carry out appropriate laboratory tests for the exclusion of primary diseases.
1. Fundus changes: optic disc congestion during papillitis, mild elevation (below 3D), unclear margins, disappearance of physiological depression, retinal vein filling and distortion, retinal edema around the papilla, flaming hemorrhage and yellow-white exudation, Sometimes it can affect the macula to cause reflex edema and wrinkles in the macula. When the posterior optic neuritis is performed, the early fundus is basically normal, the color of the late optic papilla is light, and the optic nerve is atrophied.
2, visual field changes: the performance of the central dark spot or the side of the dark spot.
3. Electrophysiological examination: The visual evoked potential showed prolonged P wave latency and decreased amplitude.
4. Fundus fluorescein angiography: Early venous nipple surface fluorescence leakage during papillitis, blurred edges, strong fluorescence during venous phase, can be used to identify diseases with similar fundus changes and confusion, because the examination of optic nerve patients is normal.
4. Brain evoked potentials.
5, head CT, MRI examination and so on.
Diagnosis
Diagnostic differentiation of optic neuritis
diagnosis
Diagnosis can be based on medical history, clinical symptoms, and laboratory findings.
It can be diagnosed as optic neuritis according to the following 3 points: 1 far, near vision is reduced, and can not be corrected with lenses. 2, the external eye examination is normal. 3 The surrounding field of view is normal and the central field of view has a central dark spot.
Differential diagnosis
1. Identification of various poisoning (methanol, drugs, heavy metals, etc.) and nutritional deficiency diseases that can cause optic neuropathy. It is not difficult to identify from medical history and related examinations.
2, severe atherosclerosis of the ophthalmic artery, inflammatory disease or embolism can cause acute monocular vision loss, but no eye pain.
3, intracranial tumors, especially the saddle area occupying lesions, early can be retrobulbar optic neuritis changes, visual field and head X-ray can help diagnosis, head CT and MRI are more helpful for early detection.
4. Central serous chorioretinopathy and cystoid macular edema with inconspicuous changes in the fundus, clinical manifestations of visual impairment and central dark spots, often misdiagnosed as optic neuritis, but without post-ocular pain, patients have more vision The object is deformed or darkened, and the color vision disorder and pupillary disorder are not obvious in patients with optic neuritis. The eyesight is irradiated with light for about 10 seconds, and the visual acuity is measured. The visual acuity of the patients with optic neuritis is slightly decreased, and the visual acuity of the patients with macular degeneration is obviously decreased. The macular degeneration can be found in the macular area. Fundus fluorescein angiography can clearly show the leakage of central serous chorioretinopathy and cystoid macular edema, while angiography in patients with optic neuritis is normal.
5, slow onset of optic neuritis should also be differentiated from pseudo-blind and rickets, ocular electrophysiological examination can often help to make a differential diagnosis.
