NEURO-OPHTHALMOLOGY & STRABISMUS

Anisocoria is having one pupil (the black circle in the center of the eye) larger or smaller than the other pupil. In some people a small difference in size between the two pupils is normal. Anisocoria may occur suddenly due to injury, eye disorders or neurological disorders.

Signs/Symptoms

• Uneven pupil size
• Blurry vision
• Sensitivity to light
• Eye pain
• Headache
• Stiff neck
• Nausea

Treatment

Medical evaluation is important to determine the cause of anisocoria. For an injury resulting in anisocoria, immediate medical treatment is recommended. If an infection is the cause, antibiotic or antiviral eye drops may be given. Neurological disorders may require surgery.

Seeing two images of a single object (diplopia) is monocular when the double vision remains when covering one eye, or binocular when the eyes point in different directions and covering one eye results in a single image. The pattern of eye movements and measurements of eye alignment help determine the area of the disorder such as the brain, nerves or muscles.

Signs/Symptoms

• Double vision
• Blurred vision
• Appearance of "crossed eyes"

Treatment

Treatment is tailored to the cause of the double vision. For example, monocular double vision may be helped if the patient needs eyeglasses or perhaps a cataract has been found so surgery is necessary. Binocular diplopia may be caused by more serious conditions such as stroke or trauma, or by diseases such as myasthenia gravis and nerve palsies that require immediate medical attention.

Idiopathic intracranial hypertension is elevated pressure in the brain without an underlying cause. It can cause swelling of the optic nerve, which can only be detected during an eye examination.

Signs/Symptoms

• Headaches
• Blurred vision or vision loss

Treatment

Medical evaluation is important to exclude underlying causes of elevated pressure in the brain, to monitor visual function and for consideration of treatment to improve vision and headaches. Treatment is aimed at lowering pressure with medications, surgery or a combination of both.

Myasthenia gravis is an autoimmune disorder that interrupts the communication between nerve impulses and muscles causing muscle weakness and fatigue. While any skeletal muscle can be affected, the disease frequently affects the muscles in the eyelids and behind the eyes leading to droopy eyelids (ptosis) and double vision (diplopia).

Signs/Symptoms

• Droopy eyelids
• Double vision
• Weakness

Treatment

Medical consultation with a neurologist is important to confirm the diagnosis and consider treatment. Treatment often involves a variety of medications.

The optic nerves carry information from the eyes to the brain. Optic nerve disorders can cause abnormal optic nerve appearance, which can be seen during an eye examination. Optic nerve disorders include non-arteritic ischemic optic neuropathy, optic neuritis, traumatic optic neuropathy and other diseases involving the optic nerve.

Signs/Symptoms

• Blurry vision
• Decreased vision
• Eye pain
• Abnormal or diminished color vision
• Spots in the vision

Treatment

Medical evaluation is important to determine the cause and treatment of an optic nerve disorder. In some instances, optic nerve disorders may be improved with drug therapy only but additional treatment or surgery may be required if another health condition is causing the optic nerve disorder.

Optic neuritis is an autoimmune disorder causing inflammation in the optic nerve, which sends information from the eye to the brain in order to process what you are seeing.

Signs/Symptoms

• Decreased/blurry vision
• Eye pain
• Abnormal color vision

Treatment

Medical evaluation is important to confirm the diagnosis, to consider treatment options and to assess risk for future neurological events. For example, inflammation from optic neuritis may be improved after a brief course of steroids but additional treatment may be needed if another health condition is present with optic neuritis.

Strabismus is the term for non-aligned eyes. The condition occurs in children and adults. Strabismus can be congenital (present from birth) or acquired from eye injury, diabetes, stroke and other conditions. Strabismus may first appear as double vision. If left untreated in children, it can lead to visual impairment, so early diagnosis and treatment is essential.

Signs/Symptoms

• Misaligned eyes
• Squinting one eye in bright sunlight
• Head tilt
• Altered depth perception
• Double vision (typically in adults)

Treatment

A pediatric ophthalmologist should be consulted for suspected strabismus in children. Treatment varies but vision therapy options include use of computerized optical equipment, prisms, eyeglasses and patching the good eye to strengthen eye muscles. Surgery may strengthen or weaken the effect of one or more of the muscles that move the eye.

A change in vision in one or both eyes that completely resolves over time has possible causes including migraine headaches, medications and eye fatigue.

Signs/Symptoms

• Temporary blurred/altered vision

Treatment

Medical evaluation is important to determine the cause and assess risk for future episodes of vision change. A medication change or reading eye glasses may help if the problem continues. Immediate medical attention is needed should partial or total vision loss occur, even if temporary, or a sudden occurrence of eye pain and distortion.

Visual field defects may cause loss of peripheral (side) vision due to dysfunction anywhere along the visual pathway including the eye, optic nerve and brain. The kind of defect and whether it is in one or both eyes helps to determine the impaired area in the visual pathway.

Signs/Symptoms

The section of the visual field that is missing varies. Examples are:

• Loss of horizontal or vertical images
• Loss of side vision
• Black spot
• Blurred side vision but clear center vision
• Tunnel vision

Treatment

Accurate diagnosis of the cause of visual field loss will determine the treatment. Testing of visual fields may uncover tumors that affect the visual pathway or vision loss due to stroke, which need to be treated in conjunction with vision conditions.