Category: Diseases

What Is Demodex?

The Demodex mite is a type of parasite that lives on humans and can reside in hair follicles and sebaceous glands. These mites are arachnid (eight-legged) and invisible to the naked eye, varying in size from 0.1mm to 0.4 mm long. They typically live on the face and in the hair follicles of the eyebrows, eyelids, roots of the eyelashes, facial hair, and around the ears and are associated with various skin problems of the eyes and face, such as blepharitis and acne rosacea.

Demodex can affect humans at any age, but their presence increases in prevalence with increasing age. Immunity compromised patients such as diabetics, patients on long-term corticosteroids or chemotherapy, or patients who have HIV/AIDS also have increased risk and prevalence of Demodex infection. Usually, when the immune system is weakened and the parasitic population has colonized, this disease can badly damage the skin.
 

How Can Demodex Be Transmitted?

For transmission of mites from one person to another, direct contact of hair and sebaceous glands on the nose, or dust containing eggs is required. Since the disease processes begin when there is an overpopulation of Demodex, the vast majority of cases of mites go unobserved and don’t show any adverse symptoms. However, in certain cases, the mite populations migrate and multiply in the eyelashes.
 

What Are The Types Of Demodex?

There are two existing types of Demodex mites: the longer kind, Demodex folliculorum, which live in the hair follicles and the short ones, Demodex brevis, which live in the sebaceous (oil) glands in the skin.
 

What Are The Symptoms Of Demodex?

In the early stages, there are often no noticeable symptoms, but if left untreated Demodex can progress. Symptoms vary among patients and may include dry eye, red eyes, severe itching along the eyelid margin and eyebrow, especially in the morning, eyelid irritation, burning sensation, foreign body sensation that seems to originate beneath the eyelids, heavy lid, and blurry vision. One of the earliest signs of mite infestation is cylindrical dandruff (CD), which is the accumulation of fine, waxy, dry debris that collects at the base of the lash and extends up to 2 mm along the length of the lashes and is most noticeable on the upper lashes.
 

How Is Demodex Diagnosed?

Demodex mites can be diagnosed by a slit-lamp evaluation or by carefully removing and viewing an epilated eyelash under the microscope.
 

How Is Demodex Treated?

Initial treatment involves an in-office lid scrub/débridement which starts with a drop or two of long-lasting anesthetic being instilled. The lashes and eyebrows are then thoroughly débrided. Next, an antibiotic/steroid ointment is applied to help keep the mites from moving and also possibly suffocate them. The steroid also helps in calming down the inflammation secondary to the chemical and mechanical irritation of the in-office treatment, in addition to suppressing any possible inflammatory cascade associated with the decaying mites. The patient should return in 2 weeks and repeat the in-office treatment.
 

What Are The Instructions For Patients With Demodex?

The patients diagnosed with Demodex need to know a few simple instructions:

• Immediately wash bedding and pillowcases in hot water and dry in a heated dryer before beginning treatment, and once a week thereafter.
• Wash face, nostrils, hair, external ear and neck with a non-soap cleanser twice daily.
• Scrub the eyelids with a mild (baby) shampoo.
• Avoid using makeup for at least 1 week and discard all old makeup.
• Avoid oil-based cleansers, greasy makeup, lotions, and sunscreens which can provide further “food” for the mites.
• Exfoliate face once or twice a week to remove dead skin cells and trapped sebum. Keep pets away from sleeping surfaces.

With the proper medical care, treatment, and hygiene, the Demodex count usually drops to zero in 4-6 weeks without recurrence in the majority of cases. Patients receiving therapy show dramatic improvements in symptoms, eye inflammation, tear film stability and vision.

Macular degeneration, commonly referred to as age-related macular degeneration (AMD), is the single largest cause of sight loss in the developed world and affects more than 10 million Americans. It usually affects people over the age of 60, but has been known to affect those who are younger. It is a painless condition that usually affects both eyes with the loss being experienced in the central vision. It does not affect the peripheral vision, meaning that it does not cause total blindness.

What is the macula?

The macula is the most sensitive part of the retina and is responsible for our central vision and what allows us to see fine details with clarity.

Varieties of AMD

Wet AMD

Wet AMD is one variety of the condition in which abnormal blood vessels grow into the macula, leaking blood or fluid which then causes scarring and a rapid loss of central vision. Wet AMD can develop suddenly and rapid referral to a specialist is essential as it can be treated if caught quickly.

Dry AMD

Dry AMD is the most common variety of age-related macular degeneration and is a gradual deterioration of the retina as the cells die off over time and are not regenerated. Up to 15% of people with dry AMD go on to develop wet AMD, and so any sudden changes in your vision should be followed up with your optometrist as soon as possible.

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Symptoms of macular degeneration

Macular degeneration affects each person differently, which means that it can sometimes be difficult to diagnose, particularly as you may not notice any change in your vision early on in the condition. However, as the cells deteriorate, you will start to see an increasing range of symptoms, including:

• Distortion or bends in what should be straight lines (such as lampposts or door frames)
• Dark spots in your central vision
• Fading colors
• Difficulty adapting from dark to light environments
• Blurred vision
• Objects may appear to change shape, size or color, or may move or disappear
• Bright lights may be difficult to tolerate
• Words may disappear while you are reading

Is there any way I can reduce my risk of developing AMD?

Unfortunately, there is no clear reason as to what triggers the process that causes macular degeneration. However, you are at an increased risk if you have a family history of the condition, or if you are over 60. 

Experts suggest that the best thing you can do to minimize any potential risk is to ensure that you live a healthy, active lifestyle. You can do this by:

• Stopping smoking
• Eating a healthy, balanced diet with plenty of fruit and vegetables
• Moderating your alcohol consumption
• Maintaining a healthy weight
• Getting regular exercise

There is also some limited research that suggests that eating leafy, green vegetables can slow the deterioration of vision in cases of dry AMD.

Treatment for AMD

Sadly, there is currently no cure for either variety of AMD. In the case of dry AMD, the treatments suggested are done so with the aim of aiding the patient to make the most of their remaining vision. This can include things such as using magnifying glasses to help with reading.

Wet AMD can be treated with anti-vascular endothelial growth factor medication. This should stop additional blood vessels from developing and stop your vision from deteriorating further.

Occasionally, laser therapy is suggested as a possible treatment for destroying abnormal blood cells, but this is only suitable for cases of wet AMD and usually only around 1 in 7 sufferers may be potential candidates for this procedure.

If you have any questions or concerns regarding macular degeneration, we highly recommend that you speak with your optometrist who will be happy to assist you.