Trauma can also cause a hyphema or hemorrhage into the anterior chamber The degree of visual impairment in the affected eye ranges from little to severe, depending on the extent of bleeding and associated trauma Complications of hyphema include rebleeding, which typically occurs within the first days after injury, and increased intraocular pressure potentially leading to glaucoma Previously, all patients with hyphema were hospitalized on strict bed rest However, this was not shown to improve outcome, but close follow-up with an ophthalmologist is recommended Despite lack of definitive evidence, most ophthalmologists recommend cycloplegic and corticosteroid drops to reduce pain and possibly reduce inflammatory complications Nonsteroidal anti-inflammatory drugs (NSAIDs) should be avoided The risk of vision loss is highest in patients with sickle cell disease or trait, when greater than 20% of the visual field is affected, with rebleeding, and when residual blood lasts beyond to days duration Traumatic injuries can lead to cataract formation, usually within a few days of injury, but onset may be delayed for years Dislocation of the lens after trauma causes significant visual impairment but can be recognized easily with a careful examination Glaucoma and retinal detachment may be late complications of blunt trauma Pain around the eye, blurred vision, and occasionally, nausea and vomiting in a patient with glaucoma or with a recent eye injury may represent an acute attack of glaucoma If any one of these is noted as a primary complaint or an incidental finding, immediate referral is required TABLE 30.2 COMMON CONDITIONS THAT CAUSE ACUTE VISUAL DISTURBANCES Trauma Migraine Chemical burns Hyphema Ruptured globe Periorbital infection Conjunctivitis The uvea consists of the iris, ciliary body, and choroid One or all portions of the uvea may become inflamed, causing uveitis Iritis and iridocyclitis may be called anterior uveitis, whereas inflammation of the choroid is often called posterior uveitis The etiologies may be divided into infectious and noninfectious Infectious uveitis may be caused by viruses, bacteria, fungi, or helminths The most common cause of posterior uveitis in children is toxoplasmosis Noninfectious causes include juvenile idiopathic arthritis, trauma, ankylosing spondylitis, Behỗet disease, idiopathic intracranial hypertension (formerly called pseudotumor cerebri), peripheral uveitis, sarcoidosis, and sympathetic ophthalmia Vogt–Koyanagi–Harada syndrome is a panuveitis with meningeal and cutaneous findings Prompt treatment of this syndrome is necessary for optimal visual outcome TABLE 30.3 CAUSES OF ACUTE DIPLOPIA Blowout fractures Poisoning Central nervous system pathology (tumor, bleed, idiopathic intracranial hypertension) Shunt malfunction Arnold–Chiari malformation Myasthenia gravis Head trauma TABLE 30.4 EMERGENT CONDITIONS THAT CAUSE VISUAL DISTURBANCES Alkali or acid burns Central retinal artery occlusion Ruptured globe In addition to blurred vision in one or both eyes, anterior uveitis is also associated with pain in the affected eye, headache, photophobia, and conjunctival injection On gross examination, the pupil may be constricted and have a ring of redness surrounding the cornea A slit lamp examination is used to confirm the diagnosis Anterior uveitis may be confused with conjunctivitis or an acute attack of glaucoma In posterior uveitis, the pain and photophobia may be less pronounced, but there may be a more pronounced visual impairment The posterior chamber is composed of the vitreous humor The vitreous gel is usually clear, and any diseases that affect the clarity will impair vision Certain chronic conditions such as uveitis can cause deposits in the vitreous humor, but the visual impairment is very gradual Infections inside the eye (endophthalmitis) usually result from a penetrating injury, surgery, or extension of a more superficial infection Bacterial infections develop more rapidly than fungal infections The child will have severe pain in or around the eye and, with bacterial infections especially, may have fever and leukocytosis The process is usually unilateral, and vision is severely compromised Purulent exudate is formed in the vitreous humor, and ophthalmoscopic examination may reveal a greenish color with the details of the retina lost A hypopyon—accumulation of pus in the anterior chamber—is usually present Either penetrating or blunt trauma (see Chapter 114 Ocular Trauma ) to the eye can lead to vitreous hemorrhage, but this is uncommon in children Diabetes mellitus, hypertension, sickle cell disease, and leukemia may cause vitreous hemorrhage as well as retinal tears, and central retinal vein occlusion There is a sudden loss or deterioration of vision in the affected eye This may present as strabismus and nystagmus in younger preverbal patients Findings on examination depend on the degree of hemorrhage Blood clots may be visible with the ophthalmoscope, or the fundus reflex may be black, obscuring the retina in more severe cases Retinal vein and artery obstruction are also uncommon in pediatric patients With central retinal artery occlusion, there is a sudden, painless, total loss of vision in one eye If only a branch is occluded, a field loss will result Ophthalmoscopic examination reveals the cherry-red spot of the fovea, the optic nerve appears pale white, and the arteries are narrowed significantly A Marcus Gunn pupil (relative afferent defect) may be present and may be diagnosed by shining a light in one eye, then in the other When the light is shone in the normal eye, both pupils will constrict When light is shone in the damaged eye, the pupil will dilate The retinal artery may be severed by trauma or obstructed by emboli, as in a patient with endocardial thrombi or arterial obstructions in systemic lupus erythematosus (SLE) and in diseases with hypercoagulability, such as sickle cell disease The arterial spasm associated with migraine may also lead to retinal artery obstruction As with retinal artery occlusion, retinal vein occlusion causes a painless loss of vision Visual loss may be severe, with total occlusion of the central retinal vein, or less pronounced, with branch obstruction Examination of the retina reveals multiple hemorrhages with a blurred, reddened optic disc The arteries are narrowed, the veins engorged, and patchy white exudates may be evident These findings will be limited to one area in branch occlusion Retinal vein obstruction, although rare, may occur with trauma or diseases such as leukemia, cystic fibrosis, or retinal phlebitis As mentioned, a tear in the retina may lead to vitreous hemorrhage, causing decreased vision in the affected eye If the tear is in the macula, the visual loss will be severe A tear in the retina may not cause immediate visual impairment Retinal detachment from a retinal tear may be delayed for years The visual impairment may go unnoticed if the detachment is peripheral As the detachment progresses or when it involves more central areas, the patient will complain of cloudy vision with lightning flashes (photopsia) This may be followed by a shadow or curtain in the visual field Visual acuity may remain normal if the macula is not involved Examination of the eye will reveal a lighter-appearing retina in the area of detachment, and it may have folds Flashing lights or visual field defects, after trauma, should raise the suspicion of retinal detachment Retinoschisis, splitting of the layers of the retina, may be seen in shaken baby syndrome Commotio retinae, or Berlin edema, is edema of the retina that may follow blunt ocular trauma by 24 hours The visual loss is variable, and the retina will appear pale gray because of the edema, but the macula is usually spared The optic nerve transmits visual signals to the cortex Optic neuritis includes inflammation or demyelination of the optic nerve The process is usually acute and may be unilateral or bilateral Loss of vision may take from hours to days, and visual impairment ranges from mild loss to complete blindness Patients often complain of disturbance of color vision Pain may be absent or present on movement of the eye or palpation of the globe It is rarely an isolated event in children Causes include meningitis, viral infections, immunizations, encephalomyelitis, Lyme disease, and demyelinating diseases Multiple sclerosis uncommonly occurs in childhood, but may present with sudden onset of intermittent episodes of optic neuritis associated with gait disturbances, paresthesias, and dysesthesias Exogenous toxins and drugs (e.g., lead poisoning, long-term chloramphenicol treatment) may also cause optic neuritis Idiopathic intracranial hypertension (IIH) is characterized by increased intracranial pressure with normal cerebrospinal fluid content, normal neuroimaging, absence of neurologic signs except cranial nerve VI palsy, and ... obscuring the retina in more severe cases Retinal vein and artery obstruction are also uncommon in pediatric patients With central retinal artery occlusion, there is a sudden, painless, total loss