Red eye (medicine)
Encyclopedia
In medicine
, red eye is a non-specific term to describe an eye
that appears red
due to illness, injury, or some other condition. Conjunctivitis
and subconjunctival hemorrhage
are two forms of a red eye.
Since it is a common affliction, primary care
doctor
s often deal with patient
s with red eyes in their practices.
The goal of the primary care doctor when presented with a red eye is to assess whether it is an emergency
in need of referral and immediate action, or instead a benign condition that can be managed easily and effectively.
Red eye usually refers to hyperemia of the superficial blood vessel
s of the conjunctiva
, sclera
or episclera
, and may be caused by disease
s or disorders of these structures or adjacent structures that may affect them directly or indirectly.
. Others include blepharitis
, acute glaucoma
, injury
, subconjunctival hemorrhage
, keratitis
, iritis
, episcleritis, scleritis
, inflamed pterygium
, inflamed pinguecula
, dry eye syndrome, airborne contaminants, a burst blood vessel
, tick borne illnesses like Rocky Mountain spotted fever, high stress levels and drug use including cannabis.
s of red eye represent warnings that the underlying cause is serious and requires immediate attention.
The person
conducting a thorough eye examination
should be attentive to the warning signs and symptoms during the eye exam.
There are six danger signs: conjunctival injection, ciliary flush (circumcorneal injection), corneal edema or opacities, corneal staining, abnormal pupil size, and abnormal intraocular pressure.
is indicative of serious ocular disease, such as cornea
l inflammation, iridocyclitis
, and glaucoma
, and never occurs in simple conjunctivitis
without concurrent corneal involvement.
A ciliary flush is a ring of red
or violet
around the cornea
of the eye.
Opacification may be detected using an ophthalmoscope or, in more obvious cases, with a pen light.
These opacities may be keratic, haze-like (usually from corneal edema
), or they may be localized such as with ulcerated corneas
or those affected by keratitis
.
staining of the eye, and careful observation with cobalt
-blue
light
.
Corneal epithelial disruptions would stain green
, which represents some injury of the corneal epithelium.
These types of disruptions may be due to corneal inflammations or physical trauma
to the cornea.
that is smaller than the other, which is caused by a reflex
muscle
spasm
of the iris
sphincter muscle.
As is the general rule, conjunctivitis does not affect the pupils.
With acute angle-closure glaucoma, the pupil would be partially dilated and oval.
If the eye is red, anterior chamber depth may indicate acute glaucoma
, which requires immediate attention.
.
It is usually affected only by iridocyclitis or acute-closure glaucoma, but not by relatively benign conditions.
In iritis and traumatic perforating ocular injuries, pressure is usually low.
of the orbit
, or a cavernous sinus disease.
Most commonly, chronic proptosis is caused by thyroid
diseases such as Graves disease.
If the blurriness improves with blink
ing, it suggests ocular surface discharge of some variety.
See a doctor if it gets worse.
may report mild irritation or scratchiness, but never extreme pain
.
Severe pain is an indicator of keratitis
, corneal ulceration, iridocyclitis
, or acute glaucoma
.
(fear of light
) is most characteristic of iritis
, but may also depend on acute glaucoma
.
s are an indication of corneal edema, and are a warning that acute glaucoma may be present.
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
, red eye is a non-specific term to describe an eye
Human eye
The human eye is an organ which reacts to light for several purposes. As a conscious sense organ, the eye allows vision. Rod and cone cells in the retina allow conscious light perception and vision including color differentiation and the perception of depth...
that appears red
Red
Red is any of a number of similar colors evoked by light consisting predominantly of the longest wavelengths of light discernible by the human eye, in the wavelength range of roughly 630–740 nm. Longer wavelengths than this are called infrared , and cannot be seen by the naked eye...
due to illness, injury, or some other condition. Conjunctivitis
Conjunctivitis
Conjunctivitis refers to inflammation of the conjunctiva...
and subconjunctival hemorrhage
Subconjunctival hemorrhage
thumb|right|250px| A stress induced subconjunctival hemorrhage in the left eye one week after hemorrhaging. Same hemorrhage four weeks after hemorrhaging. Some of the blood in the [[sclera]] has turned yellow, like a bruise....
are two forms of a red eye.
Since it is a common affliction, primary care
Primary care
Primary care is the term for the health services by providers who act as the principal point of consultation for patients within a health care system...
doctor
Physician
A physician is a health care provider who practices the profession of medicine, which is concerned with promoting, maintaining or restoring human health through the study, diagnosis, and treatment of disease, injury and other physical and mental impairments...
s often deal with patient
Patient
A patient is any recipient of healthcare services. The patient is most often ill or injured and in need of treatment by a physician, advanced practice registered nurse, veterinarian, or other health care provider....
s with red eyes in their practices.
The goal of the primary care doctor when presented with a red eye is to assess whether it is an emergency
Medical emergency
A medical emergency is an injury or illness that is acute and poses an immediate risk to a person's life or long term health. These emergencies may require assistance from another person, who should ideally be suitably qualified to do so, although some of these emergencies can be dealt with by the...
in need of referral and immediate action, or instead a benign condition that can be managed easily and effectively.
Red eye usually refers to hyperemia of the superficial blood vessel
Blood vessel
The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and...
s of the conjunctiva
Conjunctiva
The conjunctiva covers the sclera and lines the inside of the eyelids. It is composed of rare stratified columnar epithelium.-Function:...
, sclera
Sclera
The sclera , also known as the white or white of the eye, is the opaque , fibrous, protective, outer layer of the eye containing collagen and elastic fiber. In the development of the embryo, the sclera is derived from the neural crest...
or episclera
Episclera
The episclera is the outermost layer of the sclera. It is composed of loose, fibrous, elastic tissue and attaches to Tenon's capsule.A vascular plexus is found between the conjunctiva and the sclera consisting of two layers of vessels, the superficial episcleral vessels and the deep episcleral...
, and may be caused by disease
Disease
A disease is an abnormal condition affecting the body of an organism. It is often construed to be a medical condition associated with specific symptoms and signs. It may be caused by external factors, such as infectious disease, or it may be caused by internal dysfunctions, such as autoimmune...
s or disorders of these structures or adjacent structures that may affect them directly or indirectly.
Differential diagnosis
There are many causes of a red eye. The most common is conjunctivitisConjunctivitis
Conjunctivitis refers to inflammation of the conjunctiva...
. Others include blepharitis
Blepharitis
Blepharitis is an ocular condition characterized by chronic inflammation of the eyelid, the severity and time course of which can vary. Onset can be acute, resolving without treatment within 2–4 weeks , but more generally is a long standing inflammation varying in severity...
, acute glaucoma
Glaucoma
Glaucoma is an eye disorder in which the optic nerve suffers damage, permanently damaging vision in the affected eye and progressing to complete blindness if untreated. It is often, but not always, associated with increased pressure of the fluid in the eye...
, injury
Eye injury
Physical or chemical injuries of the eye can be a serious threat to vision if not treated appropriately and in a timely fashion. The most obvious presentation of ocular injuries is redness and pain of the affected eyes. This is not, however, universally true, as tiny metallic projectiles may cause...
, subconjunctival hemorrhage
Subconjunctival hemorrhage
thumb|right|250px| A stress induced subconjunctival hemorrhage in the left eye one week after hemorrhaging. Same hemorrhage four weeks after hemorrhaging. Some of the blood in the [[sclera]] has turned yellow, like a bruise....
, keratitis
Keratitis
Keratitis is a condition in which the eye's cornea, the front part of the eye, becomes inflamed. The condition is often marked by moderate to intense pain and usually involves impaired eyesight.-Types:...
, iritis
Iritis
Iritis is a form of anterior uveitis and refers to the inflammation of the iris of the eye.-Types:There are two main types of iritis: acute and chronic. They differ in numerous ways....
, episcleritis, scleritis
Scleritis
Scleritis is a serious inflammatory disease that affects the white outer coating of the eye, known as the sclera. The disease is often contracted through association with other diseases of the body, such as Wegener's granulomatosis or rheumatoid arthritis; it can also be attained through disorders...
, inflamed pterygium
Pterygium
Pterygium most often refers to a benign growth of the conjunctiva. A pterygium commonly grows from the nasal side of the sclera. It is usually present in the palpebral fissure. It is associated with, and thought to be caused by ultraviolet-light exposure , low humidity, and dust...
, inflamed pinguecula
Pinguecula
A pinguecula is a common type of conjunctival degeneration in the eye.-Presentation:It is seen as a yellow- white deposit on the conjunctiva adjacent to the limbus . It is to be distinguished clinically from pterygium, which is a wedge shaped area of fibrosis that appears to grow into the cornea....
, dry eye syndrome, airborne contaminants, a burst blood vessel
Blood vessel
The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and...
, tick borne illnesses like Rocky Mountain spotted fever, high stress levels and drug use including cannabis.
Diagnostic approach
Some signs and symptomSymptom
A symptom is a departure from normal function or feeling which is noticed by a patient, indicating the presence of disease or abnormality...
s of red eye represent warnings that the underlying cause is serious and requires immediate attention.
The person
Person
A person is a human being, or an entity that has certain capacities or attributes strongly associated with being human , for example in a particular moral or legal context...
conducting a thorough eye examination
Eye examination
An eye examination is a battery of tests performed by an ophthalmologist, optometrist, or orthoptist assessing vision and ability to focus on and discern objects, as well as other tests and examinations pertaining to the eyes....
should be attentive to the warning signs and symptoms during the eye exam.
There are six danger signs: conjunctival injection, ciliary flush (circumcorneal injection), corneal edema or opacities, corneal staining, abnormal pupil size, and abnormal intraocular pressure.
Visual acuity
Reduced visual acuityVisual acuity
Visual acuity is acuteness or clearness of vision, which is dependent on the sharpness of the retinal focus within the eye and the sensitivity of the interpretative faculty of the brain....
is indicative of serious ocular disease, such as cornea
Cornea
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Together with the lens, the cornea refracts light, with the cornea accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is...
l inflammation, iridocyclitis
Iridocyclitis
Iridocyclitis, a type of anterior uveitis, is a condition in which the uvea of the eye is inflamed.Iridocyclitis isInflammation of the iris and the ciliary body.- Symptoms :Symptoms include:* Photophobia* Redness* Watering of the eyes* Lacrimation...
, and glaucoma
Glaucoma
Glaucoma is an eye disorder in which the optic nerve suffers damage, permanently damaging vision in the affected eye and progressing to complete blindness if untreated. It is often, but not always, associated with increased pressure of the fluid in the eye...
, and never occurs in simple conjunctivitis
Conjunctivitis
Conjunctivitis refers to inflammation of the conjunctiva...
without concurrent corneal involvement.
Ciliary flush
Ciliary flush is usually present in eyes with corneal inflammation, iridocyclitis or acute glaucoma, though not simple conjunctivitis.A ciliary flush is a ring of red
Red
Red is any of a number of similar colors evoked by light consisting predominantly of the longest wavelengths of light discernible by the human eye, in the wavelength range of roughly 630–740 nm. Longer wavelengths than this are called infrared , and cannot be seen by the naked eye...
or violet
Violet (color)
As the name of a color, violet is synonymous with a bluish purple, when the word "purple" is used in the common English language sense of any color between blue and red, not including either blue or red...
around the cornea
Cornea
The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Together with the lens, the cornea refracts light, with the cornea accounting for approximately two-thirds of the eye's total optical power. In humans, the refractive power of the cornea is...
of the eye.
Corneal opacification
Corneal opacities always indicate that a serious disease process is in progress.Opacification may be detected using an ophthalmoscope or, in more obvious cases, with a pen light.
These opacities may be keratic, haze-like (usually from corneal edema
Edema
Edema or oedema ; both words from the Greek , oídēma "swelling"), formerly known as dropsy or hydropsy, is an abnormal accumulation of fluid beneath the skin or in one or more cavities of the body that produces swelling...
), or they may be localized such as with ulcerated corneas
Corneal ulcer
A corneal ulcer, or ulcerative keratitis, is an inflammatory condition of the cornea involving loss of its outer layer. It is very common in dogs and is sometimes seen in cats...
or those affected by keratitis
Keratitis
Keratitis is a condition in which the eye's cornea, the front part of the eye, becomes inflamed. The condition is often marked by moderate to intense pain and usually involves impaired eyesight.-Types:...
.
Corneal epithelial disruption
Corneal epithelial disruptions may be detected with fluoresceinFluorescein
Fluorescein is a synthetic organic compound available as a dark orange/red powder soluble in water and alcohol. It is widely used as a fluorescent tracer for many applications....
staining of the eye, and careful observation with cobalt
Cobalt
Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....
-blue
Blue
Blue is a colour, the perception of which is evoked by light having a spectrum dominated by energy with a wavelength of roughly 440–490 nm. It is considered one of the additive primary colours. On the HSV Colour Wheel, the complement of blue is yellow; that is, a colour corresponding to an equal...
light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...
.
Corneal epithelial disruptions would stain green
Green
Green is a color, the perception of which is evoked by light having a spectrum dominated by energy with a wavelength of roughly 520–570 nanometres. In the subtractive color system, it is not a primary color, but is created out of a mixture of yellow and blue, or yellow and cyan; it is considered...
, which represents some injury of the corneal epithelium.
These types of disruptions may be due to corneal inflammations or physical trauma
Physical trauma
Trauma refers to "a body wound or shock produced by sudden physical injury, as from violence or accident." It can also be described as "a physical wound or injury, such as a fracture or blow." Major trauma can result in secondary complications such as circulatory shock, respiratory failure and death...
to the cornea.
Pupillary abnormalities
An eye with iridocyclitis would have one pupilPupil
The pupil is a hole located in the center of the iris of the eye that allows light to enter the retina. It appears black because most of the light entering the pupil is absorbed by the tissues inside the eye. In humans the pupil is round, but other species, such as some cats, have slit pupils. In...
that is smaller than the other, which is caused by a reflex
Reflex
A reflex action, also known as a reflex, is an involuntary and nearly instantaneous movement in response to a stimulus. A true reflex is a behavior which is mediated via the reflex arc; this does not apply to casual uses of the term 'reflex'.-See also:...
muscle
Muscle
Muscle is a contractile tissue of animals and is derived from the mesodermal layer of embryonic germ cells. Muscle cells contain contractile filaments that move past each other and change the size of the cell. They are classified as skeletal, cardiac, or smooth muscles. Their function is to...
spasm
Spasm
In medicine a spasm is a sudden, involuntary contraction of a muscle, a group of muscles, or a hollow organ, or a similarly sudden contraction of an orifice. It is sometimes accompanied by a sudden burst of pain, but is usually harmless and ceases after a few minutes...
of the iris
Iris (anatomy)
The iris is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupils and thus the amount of light reaching the retina. "Eye color" is the color of the iris, which can be green, blue, or brown. In some cases it can be hazel , grey, violet, or even pink...
sphincter muscle.
As is the general rule, conjunctivitis does not affect the pupils.
With acute angle-closure glaucoma, the pupil would be partially dilated and oval.
Shallow anterior chamber depth
Shallow anterior chamber depth usually indicates some problem.If the eye is red, anterior chamber depth may indicate acute glaucoma
Glaucoma
Glaucoma is an eye disorder in which the optic nerve suffers damage, permanently damaging vision in the affected eye and progressing to complete blindness if untreated. It is often, but not always, associated with increased pressure of the fluid in the eye...
, which requires immediate attention.
Abnormal intraocular pressure
Intraocular pressure should be measured as part of the routine eye examinationEye examination
An eye examination is a battery of tests performed by an ophthalmologist, optometrist, or orthoptist assessing vision and ability to focus on and discern objects, as well as other tests and examinations pertaining to the eyes....
.
It is usually affected only by iridocyclitis or acute-closure glaucoma, but not by relatively benign conditions.
In iritis and traumatic perforating ocular injuries, pressure is usually low.
Proptosis
Proptosis, or forward displacement of the globe, may be caused by an infectionInfection
An infection is the colonization of a host organism by parasite species. Infecting parasites seek to use the host's resources to reproduce, often resulting in disease...
of the orbit
Orbit (anatomy)
In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents...
, or a cavernous sinus disease.
Most commonly, chronic proptosis is caused by thyroid
Thyroid
The thyroid gland or simply, the thyroid , in vertebrate anatomy, is one of the largest endocrine glands. The thyroid gland is found in the neck, below the thyroid cartilage...
diseases such as Graves disease.
Important warning symptoms
There are three main danger symptoms in a red eye: reduced visual acuity, severe ocular pain, and photophobia (light sensitivity).Blurry vision
Blurry vision often indicates serious ocular disease.If the blurriness improves with blink
Blink
Blinking is the rapid closing and opening of the eyelid. It is an essential function of the eye that helps spread tears across and remove irritants from the surface of the cornea and conjunctiva. Blink speed can be affected by elements such as fatigue, eye injury, medication, and disease...
ing, it suggests ocular surface discharge of some variety.
See a doctor if it gets worse.
Severe pain
Those suffering from conjunctivitisConjunctivitis
Conjunctivitis refers to inflammation of the conjunctiva...
may report mild irritation or scratchiness, but never extreme pain
Pain
Pain is an unpleasant sensation often caused by intense or damaging stimuli such as stubbing a toe, burning a finger, putting iodine on a cut, and bumping the "funny bone."...
.
Severe pain is an indicator of keratitis
Keratitis
Keratitis is a condition in which the eye's cornea, the front part of the eye, becomes inflamed. The condition is often marked by moderate to intense pain and usually involves impaired eyesight.-Types:...
, corneal ulceration, iridocyclitis
Iridocyclitis
Iridocyclitis, a type of anterior uveitis, is a condition in which the uvea of the eye is inflamed.Iridocyclitis isInflammation of the iris and the ciliary body.- Symptoms :Symptoms include:* Photophobia* Redness* Watering of the eyes* Lacrimation...
, or acute glaucoma
Glaucoma
Glaucoma is an eye disorder in which the optic nerve suffers damage, permanently damaging vision in the affected eye and progressing to complete blindness if untreated. It is often, but not always, associated with increased pressure of the fluid in the eye...
.
Photophobia
PhotophobiaPhotophobia
Photophobia is a symptom of abnormal intolerance to visual perception of light. As a medical symptom photophobia is not a morbid fear or phobia, but an experience of discomfort or pain to the eyes due to light exposure or by presence of actual physical photosensitivity of the eyes, though the term...
(fear of light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...
) is most characteristic of iritis
Iritis
Iritis is a form of anterior uveitis and refers to the inflammation of the iris of the eye.-Types:There are two main types of iritis: acute and chronic. They differ in numerous ways....
, but may also depend on acute glaucoma
Glaucoma
Glaucoma is an eye disorder in which the optic nerve suffers damage, permanently damaging vision in the affected eye and progressing to complete blindness if untreated. It is often, but not always, associated with increased pressure of the fluid in the eye...
.
Coloured halos
Coloured haloHalo (optical phenomenon)
A halo from Greek ἅλως; also known as a nimbus, icebow or gloriole) is an optical phenomenon produced by ice crystals creating colored or white arcs and spots in the sky. Many are near the sun or moon but others are elsewhere and even in the opposite part of the sky...
s are an indication of corneal edema, and are a warning that acute glaucoma may be present.