What is blepharitis? What causes blepharitis?
What is blepharitis?
Blepharitis is a common eye condition that is not specific to any one group of people. 1 It is common across: 1
Blepharitis is a condition of the eyelids around the base of the eyelashes.
- Children and adults
- All ethnic groups
- All ages.
Health care professionals specializing in eye care have confirmed the high rate of blepharitis among ocular conditions. A survey in the US in 2009 found that 37% of patients seen by ophthalmologists, and almost half, 47%, of patients seen by optometrists had shown signs of blepharitis. 1,2
An estimate of the total number of cases at any one time in the US can be drawn from data from 1982, when there were nearly 600,000 patient consultations about blepharitis. 1
In the wider population, however, among people who consult a primary care doctor, blepharitis is less of a burden, accounting for about 5% of visits to the doctor. 3
The specific way in which blepharitis affects an individual is categorized by whether it has had a recent onset - acute - or has been a longstanding problem - chronic. 1 It is further described by the exact location of the problem, whether at the front or the back of the eyelid. 1
For most purposes, blepharitis is a term concerned with the chronic version of the inflammation. 1,3 which is, therefore, also the focus of this information page.
The following YouTube video, from the American Academy of Ophthalmology, gives a very short and straightforward visual description of blepharitis (excuse the pun - but blink and you'll miss it).
Fast facts on blepharitis
Here are some key points about blepharitis. More detail and supporting information is in the body of this article.
- Blepharitis is an inflammatory condition affecting the area around the base of the eyelashes.
- It can be acute, but that form is better described as eyelid infection (bacterial or viral), whereas chronic forms of the inflammation are diagnosed as blepharitis.
- If the condition affects the top, outer side of the front of the eyelids, it is called anterior blepharitis, a condition with a disease process similar to that of seborrheic dermatitis of the face and scalp.
- If the condition affects the underside of the front of the eyelids (the moist side in contact with the eye near the eyelashes), it is called posterior blepharitis. This shows a similar disease process to the anterior version, but also specifically affects the little glands that secrete an oily substance onto the eye.
- While the disease process is well described, the underlying causes of chronic blepharitis are not well understood.
- Bacteria can be associated with the condition - usually staphylococcal infection.
- The most obvious signs of blepharitis are redness and sticky clumping of scales of the skin around the base of the eyelashes.
- The main treatment, with or without the help from prescription drug ointments from the doctor, is not curative - but it is effective at managing the symptoms.
- This takes the form of a lifelong, twice-daily "hygiene" routine (although the disease is not caused by poor hygiene). This is a ten-minute process of loosening the crusts by use of warm compresses, and cleaning them away with "scrubs."
- The form of blepharitis affecting the glands near the base of the eyelids is also helped by a form of massage to help express the thicker and sometimes blocked contents.
What causes blepharitis?
The cause of blepharitis differs by type, whether acute or chronic, and for the latter cases, by whether it affects the outside or the underside of the eyelids. With blepharitis, however, "cause" relates to observations of the disease processes that take place, yet the underlying reason for the inflammatory condition is not understood. 3-5
Acute blepharitis can be ulcerative or non-ulcerative: 5
- Ulcerative acute blepharitis is usually caused by an infection - usually bacterial and usually staphylococcal. A viral cause is also possible - example infections are herpes simplex and varicella zoster.
- Non-ulcerative acute blepharitis is usually an allergic reaction. Examples of this include atopic blepharo-dermatitis, seasonal allergic blepharo-conjunctivitis, and dermato-blepharo-conjunctivitis.
The diagnosis of blepharitis is usually concerned with the chronic forms - the focus of this article. Although academic descriptions classify up to six specific forms of chronic blepharitis, 4 for practical purposes it is enough to look at two broad types according to the part of the eyelids affected: 1,3-6
- In anterior blepharitis affecting the outer part of the front of the eyelids, a bacterial (usually staphylococcal) or seborrheic disease process is involved. Seborrhea is poorly understood; it is dandruff when it affects the scalp. 7 Patients with anterior blepharitis often also have seborrheic dermatitis of the face and scalp, or another skin condition called acne rosacea .
- In posterior blepharitis affecting the underside of the front of the eyelids, there is a problem with the glands near the base of the eyelashes (the condition is also known as Meibomian gland dysfunction, MGD). The glands over-secrete their oily substance or become blocked; why this happens is not well understood, although it is often associated with acne rosacea, and hormonal causes are among the proposed theories. Posterior blepharitis can also be associated with seborrheic dermatitis.
Signs and symptoms of blepharitis
The main features of blepharitis are the following problems with the eyelids: 1
The crusting may be more prominent on waking in the morning - all the symptoms generally tend to be worse at this time. 1,3,4,6
Complaints also include: 1,3,4
- Sensations of burning, itching, irritation or that there is a foreign body or a grittiness in the eyes
- Excessive eye watering, tears (epiphora )
- Conversely, dry eyes (especially with posterior blepharitis)
- Stickiness of the eyes
- Oversensitivity to light (photophobia)
- Intolerance to wearing contact lenses.
Blepharitis is not a sight-threatening problem, but it can result in decreased vision, which can come and go. 1,4
The condition usually affects both eyes 3,4 - is bilateral - and if it is present for only one eye, this may alert doctors to an alternative diagnosis. 4
The symptoms of blepharitis over the course of a long time of living with the condition tend to come and go - there are periods of intermission when the symptoms are reduced, but other times when there are exacerbations during a flare up. 3
Signs of blepharitis - that is, the problems that can be seen by a doctor - help to diagnose the condition, so these are covered in the next section now.
Diagnosis and tests for blepharitis
Broadly, there are three types of blepharitis - one known as acute blepharitis (which may be diagnosed as lid infection instead) and two that are chronic (which are also known as lid inflammation). 3
Chronic blepharitis is usually either anterior blepharitis or posterior blepharitis (also known as Meibomian gland
dysfunction, MGD): 3,6
- Anterior blepharitis affects the outer side of the front of the eyelids
- Posterior blepharitis affects the underside of the front of the eyelids (the moist side in contact with the eye).
In a case that shows both anterior and posterior blepharitis, the diagnosis is termed marginal blepharitis. 3
Doctors will first determine a diagnosis of blepharitis by asking about symptoms - by taking a history. Confirmation of symptoms listed above will be accompanied by an examination of the eyelids and eyes.
Slit-lamp examination to find signs of blepharitis
The examination by a doctor will look out for signs that help them to tell the specific types of blepharitis apart, and then to further sub-diagnose the problem depending on the appearance of various features. 3
A suspected case of blepharitis is best examined under a slit-lamp.
Initial consultations may involve examinations without any special equipment until a more specialized examination is possible using a slit lamp.
A slit lamp is a specially developed, low-power microscope with an intense thin-beam light source for looking at the outside of the eyes and the eyelids while the patient's head is rested steady at the chin and forehead. 8
It is a familiar piece of kit at the optometrist's office when people get their eyesight checked.
Anterior blepharitis tends to show the following signs seen by a doctor under the slit lamp: 3
- Redness (erythema) and swelling (edema ) of the eyelid margin, and telangiectasia (appearance of small blood vessels because they are widened) on the outside of the eyelid
- Brittle scales in the eyelashes, forming "collarettes" around the lashes, from the base up as they grow
- Eyelashes pointing toward the eye (trichiasis) in severe and chronic cases
- Depigmentation (loss of color) of the eyelashes (poliosis)
- Loss of eyelashes (madarosis)
- Ulceration and scarring of the eyelid, and scarring of the cornea.
Posterior blepharitis tends to show the following signs more prominently: 3
- Meibomian glands may be capped with oil, dilated, or obstructed
- The glands' secretions may be thicker
- Telangiectasias and lid scarring may also be present in the area around the glands.
A sign common to all diagnoses of chronic blepharitis is revealed by examination of the tear film - the moisture over the eyes. This may be "instable," evaporating rapidly due to the abnormal lipid composition of the secretion from the Meibomian glands. 5
Treatment and prevention of blepharitis
Self-care and home treatment of blepharitis
Eyelid hygiene is the mainstay of treatment for both types of blepharitis, something that should be maintained even during the time when symptoms have come under control. 3 Self-care is still the most important element of treatment when augmented by help from a doctor or eye care specialist.
The condition cannot be cured, but home treatment is successful at helping to manage it. 3,4
If the home care is not maintained after symptoms clear up - perhaps because of the burden of doing it or a false hope that the problem has been "cured" - the symptoms will recur. Doctors call lid hygiene the "maintenance therapy" of blepharitis. 4
In addition to home treatment, people with the eyelid inflammation should avoid using cosmetics such as eyeliner, mascara and other make-up. 4,11
Lid hygiene for the management of both types of blepharitis is a two-part process, and for posterior blepharitis, a third element is added: 3,4,6,9,10
- Warm compresses - to loosen crusts
- Lid cleansing - to remove crusts
- Massage - to express the small oil glands of the eyelids.
A warm compress helps to soften and loosen oily plugs and crusts, by liquefying sebum and dilating the ducts of the glands secreting it. 4,5
It simply means placing a warm cloth over closed eyelids, and as soon as it begins to cool, reheating it in warm water and reapplying. This is continued for up to 10 minutes. 4,5
Take care with warm compresses. Follow the warnings of doctors who have shared patients' experiences in a medical journal: 11
- Some had suffered facial burns by using a microwave to heat up the wet cloth (dipping the cloth in warm water only is a better idea).
- One patient resorted to using a toothbrush vigorously, causing damage to his skin and eye.
Lid cleansing is then possible after a warm compress, and this simply involves gently rubbing the margin of the eyelid (where the bases of the eyelashes and the glands are) with a cotton swab wetted in a dilute solution of baby shampoo (2 or 3 drops in about half a cup of warm water). 4,5
This lid hygiene needs to be maintained as a self-care regime twice a day every day, so this does demand a lot of commitment, and it is needed lifelong - but the recurrence of troublesome symptoms in the absence of such a routine proves its worth. 3,4,6
This hygiene is necessary for both types of blepharitis, and the third element - massage - is necessary for people who have the type that affects the underside of the eyelids (the moist side in contact with the eye) - known as posterior blepharitis or Meibomian gland dysfunction (MGD).
The massage helps to express the oily contents of the glands, which will have loosened after the warm compress. There is a particular motion needed: a finger or a cotton-tipped applicator/swab is turned in small circles at the margin of the eyelid (where the eyelashes and glands are). 3,4,6,9,10
Eye masks are available commercially, but they achieve the same as the warm cloth compresses. They may be preferable in terms of convenience, especially given the need for a twice-daily lifelong regime. Eye scrubs can also be purchased by patients, who tend to prefer these as an alternative to the use of dilute baby shampoo. 4
Replacement tear drops or "artificial tears" available without a prescription will help to counter the dryness of the eyes caused by blepharitis during the day. Similarly, bland ointments available from the pharmacy may help to retain moistness in the eyes overnight. 5
Antibiotics and other prescribed medicines for blepharitis
Still in the year 2014 there are no guidelines for doctors to follow in the recommended treatment of blepharitis, and the need for further clinical trials remains, to establish the benefits of drug treatments added to self-care. 12
Recent trials have, however, shown that antibiotics and topical corticosteroids can produce significant improvements. 12 Doctors will try these if hygiene alone has not worked, and antibiotic ointments are always indicated in acute cases of blepharitis that have a bacterial cause (and antiviral drugs taken by mouth for acute viral cases). 5
The idea of combination drug ointments that may be prescribed by doctors is to address both the infectious and inflammatory elements of the blepharitis. 12
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