Anterior or Posterior?
Anterior or Posterior?
When signs and symptoms of blepharitis masquerade as other conditions, it’s critical to get your diagnosis right. Here’s how.
KAREN APPOLD, CONTRIBUTING EDITOR
A recent study shows that 182 million U.S. patients experienced some blepharitis symptom within a year, yet only 4.5 million were treated for it.1
Diagnosing blepharitis can be difficult because signs and symptoms can masquerade as other conditions, such as dry eye disease, says Chuck Aldridge, O.D., M.B.A., Aldridge Eye Institute, Burnsville, N.C.
“If a patient is vague about symptoms or cleans off any signs of blepharitis, such as crustiness on the eyelids, it can make diagnoses even more difficult,” he explains.
Until recently, O.D.s viewed blepharitis as more of an annoyance than a serious problem, says Caroline A. Blackie, O.D., F.A.A.O., Ph.D., senior research scientist, TearScience Inc., Boston, Mass. The reason: Most likely a lack of awareness that it can lead to significant ocular surface disease, lid margin scarring, lash loss and corneal ulceration, she explains.
Marginal blepharitis is an inflammation of the lid margin and includes both anterior and posterior blepharitis. A patient can have one type or both, she says.
Anterior blepharitis is inflammation of the lid margin anterior to the gray line. The typical signs: squamous debris, collarettes, crusting around the lashes and on the skin in the lash base area and red and irritated skin, Dr. Blackie says.
Anterior staphylococcal blepharitis is more common in females aged 42 and younger. The seborrheic type appears gender indiscriminate and affects the senior population. It is 25% to 40% more likely to be associated with aqueous-deficient dry eye (as opposed to evaporative), Dr. Aldridge says. Also, these patients are likely to have underlying dermatitis, eczema or rosacea that requires dermatology workups and treatment.
Posterior blepharitis is characterized by redness, posterior lid margin inflammation, symptoms of dry eye and irritated eyes. Additional signs pertain to the inflammation’s specific cause, Dr. Blackie explains.
|Questions For Patients Who May Have Blepharitis|
• How long have your eyes been bothering you?
• What, in particular, bothers you?
• How long have you been experiencing this?
• Do you have crusting or crystalline deposits on your eye lids?
• Do you have fluctuating vision?
• Do your eyes burn, especially in the wind or at night?
• Do your eyes ever feel sandy or gritty?
• Do your eyelids feel itchy or dry?
• Have you noticed any thickening or redness on your eyelid margins (show patient where these are located)?
• Have you experienced unexplainable tearing?
For example, if meibomian gland dysfunction (MGD) is the primary cause, the glands release thickened or inspissated and colored secretions, minimal-to-no secretion or, less frequently, hyper-secretion. If the MGD has been on-going, the lid margin reveals other signs, such as telangiectasia, notching, epithelial overgrowth or observable changes to the line of Marx (mucocutaneous junction). If conjunctivitis is the cause, the bulbar conjunctiva is red and has accompanying characteristic discharge or additional signs of allergic conjunctivitis, such as …
Questions for the patient
To determine the presence of blepharitis, Adam J. Clarin, O.D., Clarin Eye Care Center, Palmetto Bay, Fla., and Drs. Aldridge and Blackie advise asking the patient a series of questions (see “Questions for Patients Who May Have Blepharitis,” page 21). More “yes” answers generally indicate a high severity level.
Exams and tests
To make an accurate diagnosis, the doctors recommend:
► Identifying and locating any crusting/debris on and around the lashes, visible lid area inflammation, telangiectasia, lid margin notching or epithelial overgrowth or changes to the line of Marx (which are visible with vital dye), Dr. Blackie says.
► Using your slit lamp to examine the upper and lower lid margins under both high and low magnification. “It should be evident whether the problem is possibly in the eyelashes or possibly in the meibomian glands behind the lashes,” says Dr. Clarin.
► Applying lid margin pressure to see whether the glands can be physically expressed, if you suspect MGD. Normal secretions look like baby oil.
“If a patient has posterior blepharitis due to MGD, they may have a cheesy-looking discharge or none at all,” Dr. Aldridge says. “If a patient has anterior blepharitis, he or she may present with white, flaky scales on their eyelids, eyebrows and hairline.” If a patient has MGD, tears evaporate quickly, which feels like a burning, he says?
► A tear osmolarity test, which may help in diagnosing ocular surface inflammation caused by both blepharitis types and dry eye.
No universally accepted grading scales for blepharitis exist. You can assess inflammation severity by comparing it with a healthy lid margin.
“The same is true for lid crusting and other lid margin signs, such as telangiectasia, epithelial overgrowth, severity of MGD and changes to the line of Marx,” Dr. Blackie says.
Examine the minutia of the normal lid margin to ensure you can detect early, subtle blepharitic lid margin changes, she says.
The two billing components: the procedure and the diagnosis. The procedure component depends upon the service level, which varies among physicians, Dr. Aldridge says.
The most commonly used diagnosis codes:
► Unspecified blepharitis 373.00
► Meibomitis (if posterior blepharitis) 373.12
An underlying dry eye enables the use of these diagnosis codes:
► Dry eye 370.15
► Keratoconjunctivitis sicca 370.33
► Punctate keratitis (if corneal punctate staining is present) 370.21
“Unfortunately, the current codes do not distinguish well between the anterior and posterior form of the condition,” Dr. Clarin notes. “This is mainly because, until recently, this was a poorly understood condition.”
Prevention and education
To help prevent blepharitis, Dr. Blackie advises you routinely scrutinize patients’ lid margin health and function. “It is important to pay close attention to prevention as well as early and accurate diagnosis,” she says. “Educate patients about the importance and benefits of good lid hygiene and blinking practices.” OM
1. Lemp MA, Nichols KK. Blepharitis in the United States 2009: a survey-based perspective on prevalence and treatment. Ocular Surf. 2009 Apr;7 (2 Suppl): S1-S14.
|Ms. Appold is a freelance medical writer based in Royersford, Pa.
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