To understand the association between facial demodicosis and ocular demodicosis, we plan to enroll patients with facial demodicosis, ocular demodicosis, or both, in order to analyze their clinical presentations, the density of Demodex infestation over facial skin and eyelashes, and possible risk factors of the two diagnoses.

Although facial demodicosis and ocular demodicosis are described in a variety of clinical presentations, the association between the two diagnoses is not clearly identified.

Clinically, we plan to enroll 120 patients with facial demodicosis, ocular demodicosis. We will obtain their basic information, medical history, medication, and lifestyle. We will evaluate their clinical features. We will also perform quantitative tests including direct microscopic examination and cilia epilation test:

1. Direct microscopic examination: On glabella and bilateral cheeks, follicular contents in the 1-cm × 1-cm area will be squeezed out. The contents are transferred onto a glass slide, covered with mineral oil and a cover slide, and examined under the microscope.
2. Epilation: Four (4) non-adjacent cilia will be pulled from each upper eyelid and examined under the microscope. The total Demodex counts are recorded.

We will analyze the clinical presentations, the density of Demodex infestation, and possible risk factors of the two diagnoses.

Inclusion Criteria:

Patient with a diagnosis of facial demodicosis or ocular demodicosis.

A. Facial demodicosis defined as both 1 and 2:

1. Clinical presentation of facial skin matches any of the followings:

   1. Pityriasis folliculorum.
   2. Papulopustular lesion.
   3. Rosacea.

2. Demodex infestation detected by direct microscopic examination ≥ 5 mites/cm2.

   B. Ocular demodicosis defined as both 3 and 4:

3. Clinical presentation of ocular region matches any of the followings:

   1. Chronic blepharitis.
   2. Eyelash abnormalities: trichiasis, distichiasis, madarosis.
   3. Meibomian gland dysfunction.
   4. Recurrent chalazion.
   5. Ocular rosacea.

4. Demodex infestation detected by cilia epilation test ≥ 1 mite/eyelid.

Exclusion Criteria:

1. Usage of oral Ivermectin, topical Ivermectin or topical tea tree oil in the past 1 month.
2. Patient who cannot tolerate direct microscopic examination or cilia epilation test.

Patients aged 20 years or older and with a diagnosis of either facial demodicosis or ocular demodicosis.