Common Causes
Por sí misma, la anisocoria no causa síntomas. Fisiológica (presente en aproximadamente el 20% de las personas): la diferencia entre el tamaño de la pupila en la anisocoria fisiológica es típicamente ≤ a alrededor de 1 mm. Algunas causas frecuentes de anisocoria Esta foto muestra una anisocoria, una desigualdad visible en el diámetro de la pupila.
Related Conditions
Fisiológica (presente en aproximadamente el 20% de las personas): la diferencia entre el tamaño de la pupila en la anisocoria fisiológica es típicamente ≤ a alrededor de 1 mm. Algunas causas frecuentes de anisocoria Esta foto muestra una anisocoria, una desigualdad visible en el diámetro de la pupila.
Can anisocoria cause Síntomas?
Mechanical anisocoria will happen because of damage to either the iris or its supporting structures. Eye trauma, surgery, or inflammatory conditions like uveitis (inflammation of the middle tissue layer of the eye) are just some examples that could lead to mechanical anisocoria.
What is anisocoria fisiológica?
Anisocoria is greater in the dark due to a defect in the pupillary dilator response secondary to lesions along the sympathetic trunk. Central or first-order lesions are often caused by stroke, lateral medullary syndrome, neck trauma or demyelinating disease.
What causes mechanical anisocoria?
Why is anisocoria greater in the dark?
See more
What is the cause of anisocoria?
Generally, anisocoria is caused by impaired dilation (a sympathetic response) or impaired constriction (a parasympathetic response) of pupils. An injury or lesion in either pathway may result in changes in pupil size.29-Jan-2022
What cranial nerve causes anisocoria?
Even a blind eye should constrict in response to light shined on the other eye. Unequal pupils (anisocoria) are due to the efferent (motor) system, which includes CNIII, somatic and parasympathetic components, sympathetic nerves originating in the cervical spine, and the smooth muscle of the iris.
How do you measure anisocoria?
In practical terms, when faced with anisocoria, ophthalmologists need to confirm the finding by measuring pupil size in each eye in ambient room light. Then the pupils need to be measured in different light conditions (dark and bright light). It is also important to note any other obvious features such as ptosis.01-Feb-2018
Can atropine cause anisocoria?
Consequently, the patient's pupil dilation could have been caused by accidental exposure to atropine, which entered the conjunctival sac and caused anisocoria.
Can anxiety cause uneven pupils?
Because elevated stress can adversely affect the nervous system and how the sensory organs function, stress, including anxiety-caused stress, and a lack of sleep can affect the size of the pupils in the eyes.19-May-2021
How can you tell if anisocoria is physiological?
If anisocoria remains the same in both lighting conditions, and the difference between pupil sizes is no more than 2 mm, the aetiology is likely to be physiological. The presence of ptosis and/or extraocular muscle involvement suggests a pathological process regardless of the magnitude of anisocoria.
Is unequal pupil size an emergency?
For new uneven pupil size that is related to new double vision, eyelid droopiness or head, neck or eye pain, it is best to be evaluated in the emergency room.
Does anisocoria affect vision?
Depending on the underlying cause of your anisocoria, you might develop other symptoms too. For example, you might experience: blurred vision. double vision.
What is considered significant anisocoria?
Physiological Anisocoria Physiologic anisocoria is usually defined as a pupillary inequality of 0.4 mm, seldom greater than 0.8 mm, not due to a secondary cause. If the anisocoria is physiologic, the difference in pupil sizes should remain equal in dim and bright lights.02-Jan-2022
Can glaucoma cause anisocoria?
Mechanical anisocoria Eye trauma can be caused by an eye injury, eye surgery complications, angle-closure glaucoma, iritis, or uveitis. Mechanical anisocoria may also develop from an ocular tumor or congenital condition that affects the structure of the iris, such as: Total or partial absence of the iris (aniridia)11-Nov-2020
Can antidepressants cause anisocoria?
There have been some cases of anisocoria and mydriasis with the use of antidepressants, especially fluvoxamine, bupropion, paroxetine, and sertraline.
Does physiological Anisocoria go away?
Physiological anisocoria may be temporary or permanent, depending on individual cases. About 15–30% of the population experiences physiological anisocoria. The difference between the pupil sizes is more or less constant, even when the light changes, and is not usually of concern.
What cranial nerve is associated with vision?
Optic nerveOptic nerve (CN II) enables vision. Trigeminal nerve (CN V) enables sensation in your face. Vestibular and cochlear nerves (CN VII) enable balance and hearing.10-Aug-2021
Did David Bowie have anisocoria?
The word “anisocoria” literally translates into “not equal pupil condition.” However, while Bowie had a permanent case of anisocoria, the condition isn't always lasting. And the difference in pupil size isn't always as noticeable as Bowie's; the difference between the two can be as little as 0.4 millimeters.
Why does my anisocoria come and go?
While small differences in pupil size are normal and can even come and go (physiologic anisocoria), constant and significant differences in pupil sizes may be a sign of damage to the nerves that control the pupils or to the brain.
What is a third nerve palsy?
A complete third nerve palsy causes a completely closed eyelid and deviation of the eye outward and downward. The eye cannot move inward or up, and the pupil is typically enlarged and does not react normally to light.
Overview
Anisocoria is the medical term for when one of your pupils is bigger than the other.
Symptoms and Causes
Anisocoria can be accompanied by serious symptoms. Go to the emergency room if one pupil is bigger than the other and you experience any of the following:
Diagnosis and Tests
Your healthcare provider will diagnose anisocoria by looking at your eyes and performing a physical exam to check for other symptoms. You might need imaging tests, including:
Management and Treatment
Treating what’s causing anisocoria is more important than treating the irregularity in your pupils.
Prevention
Because anisocoria can be caused by such a wide range of conditions, there’s no one surefire way to prevent it. Have your eyes examined regularly, and see your provider annually for a checkup.
Living With
Visit your healthcare provider or go to the emergency room right away if you notice any changes in your eyes or vision, including if your pupils are irregularly sized.
What causes anisocoria?
Explanation3: “Generally, anisocoria is caused by impaired dilation (a sympathetic response) or impaired constriction (a parasympathetic response) of pupils. An injury or lesion in either pathway may result in changes in pupil size. Physiologic (also known as simple or essential) ...
Why is anisocoria greater in the dark?
Anisocoria is greater in the dark due to a defect in the pupillary dilator response secondary to lesions along the sympathetic trunk. Central or first-order lesions are often caused by stroke, lateral medullary syndrome, neck trauma or demyelinating disease.
What causes pupils to be unequal?
An injury or lesion in either pathway may result in changes in pupil size. Physiologic (also known as simple or essential) anisocoria is the most common cause of unequal pupil sizes, affecting up to 20% of the population. [1] .
Which anticholinergic drugs cause mydriasis?
Anticholinergics such as atropine, homatropine, tropicamide, scopolamine and cyclopentolate lead to mydriasis and cycloplegia by inhibiting parasympathetic M3 receptors of the pupillary sphincter and ciliary muscles.
What are some examples of mechanical anisocoria?
Examples include aniridia, coloboma and ectopic pupil. Mechanical anisocoria is an acquired defect that results from damage to the iris or its supporting structures. Causes include physical injury from ocular trauma or surgery, inflammatory conditions such as iritis or uveitis, angle closure glaucoma leading to iris occlusion ...
Is anisocoria intermittent?
Light and near responses is intact, and the degree of anisocoria is typically equal in light and dark. Physiologic anisocoria may be intermittent and even self-resolving. However, many cases are persistent. Congenital anomalies in the structure of the iris may contribute to abnormal pupillary sizes and shapes that present in childhood.
Why is anisocoria greater in the dark?
Anisocoria is greater in the dark due to a defect in the pupillary dilator response secondary to lesions along the sympathetic trunk. Central or first-order lesions are often caused by stroke, lateral medullary syndrome, neck trauma or demyelinating disease.
What causes an unequal pupil size?
Generally, anisocoria is caused by impaired dilation (a sympathetic response) or impaired constriction (a parasympathetic response) of pupils. An injury or lesion in either pathway may result in changes in pupil size. Physiologic (also known as simple or essential) anisocoria is the most common cause of unequal pupil sizes, ...
What causes adie's tonic pupil?
Causes include Adie’s tonic pupil, oculomotor nerve palsy, traumatic injury to the iris, or pharmacologic dilation from mydriatics/cycloplegics (atropine, tropicamide, cyclopentolate), or cocaine. The use of pilocarpine can be diagnostic in this setting.
What is Horner's syndrome?
Horner’s syndrome (oculosympathetic palsy) is classically described by the triad of ptosis, miosis, and anhidrosis, although clinical presentations may vary. Anisocoria is greater in the dark due to a defect in the pupillary dilator response secondary to lesions along the sympathetic trunk.
What is autoimmune ganglionopathy?
Autoimmune autonomic ganglionopathy is a disorder of autoantibodies that target autonomic ganglia . It affects sympathetic and parasympathetic systems that may result in pupillary abnormalities, anisocoria, orthostatic hypotension, and anhidrosis .
What are some examples of congenital anomalies in the iris?
Examples include aniridia, coloboma, and ectopic pupil. Mechanical anisocoria is an acquired defect that results from damage to the iris or its supporting structures.
What is anisocoria?
Anisocoria is a condition characterized by unequal pupil sizes. It is relatively common, and causes vary from benign physiologic anisocoria to potentially life-threatening emergencies. Thus, thorough clinical evaluation is important for the appropriate diagnosis and management of the underlying cause.
1. Golpes en la cabeza
Cuando se sufre un golpe fuerte en la cabeza, debido a un accidente de tránsito o durante un deporte de alto impacto, por ejemplo, puede desarrollarse un traumatismo craneoencefálico, en el que surgen pequeñas fracturas en el cráneo.
2. Migraña
En varios casos de migraña, el dolor puede acabar afectando los ojos, lo que podría provocar no solo la caída de uno de los párpados, sino también la dilatación de una de las pupilas.
3. Inflamación del nervio óptico
La inflamación del nervio óptico, también conocida como neuritis óptica, puede ocurrir debido a varias causas, surgiendo normalmente en personas con enfermedades autoinmunes, como esclerosis múltiple, o con infecciones virales, como varicela o tuberculosis.
4. Tumor cerebral, aneurisma o ACV
Además del traumatismo craneoencefálico, cualquier alteración cerebral, como un tumor desarrollándose, un aneurisma o incluso un ACV, pueden causar presión sobre una parte del cerebro y ocasionar una alteración del tamaño de las pupilas.
5. Pupila de Adie
Este es un síndrome bastante inusual en el que una de las pupilas no reacciona a la luz, permaneciendo constantemente dilatada como si se estuviese siempre en un sitio oscuro. De esta forma, este tipo de anisocoria puede identificarse de forma más fácil cuando se está expuesto al sol o cuando se toma una fotografía con flash, por ejemplo.
6. Uso de medicamentos y otras sustancias
Algunos medicamentos pueden causar anisocoria después de su uso, como la clonidina, diferentes tipos de colirios, los adhesivos de escopolamina y el ipratropio en aerosol, si entran en contacto con los ojos.
1. Pancadas na cabeça
Quando se sofre uma pancada forte na cabeça, devido a um acidente de trânsito ou durante um esporte de alto impacto, por exemplo, pode se desenvolver um traumatismo craniano, no qual pequenas fraturas surgem no crânio.
2. Enxaqueca
Em vários casos de enxaqueca, a dor pode acabar afetando os olhos, o que pode provocar não só a caída de uma das pálpebras, mas também dilatação de uma das pupilas.
3. Inflamação do nervo ótico
A inflamação do nervo ótico, também conhecida como neurite ótica, pode acontecer devido a várias causas, mas normalmente surge em pessoas com doenças autoimunes, como esclerose múltipla, ou com infecções virais, como catapora ou tuberculose.
4. Tumor cerebral, aneurisma ou AVC
Além do traumatismo craniano, qualquer alteração cerebral como um tumor se desenvolvendo, um aneurisma ou até um AVC, podem causar pressão sobre uma parte do cérebro e acabar alterando o tamanho das pupilas.
5. Pupila de Adie
Esta é uma síndrome bastante rara na qual uma das pupilas não reage à luz, ficando constantemente dilatada, como se estivesse sempre num local escuro. Assim, este tipo de anisocoria pode ser mais facilmente identificado quando se está exposto ao sol ou quando se tira uma fotografia com flash, por exemplo.
6. Uso de medicamentos e outras substâncias
Alguns medicamentos podem causar anisocoria após seu uso, como a clonidina, diferentes tipos de colírios, adesivo de escopolamina e ipratrópio em aerossol, se em contato com o olho.