One drop for each eye, four times per day for over 4 weeks.

Eye discomfort VAS scale: for the eye symptoms of self-assessment. Dry eye symptoms include itching, foreign body sensation, burning sensation, pain, dry, blurred vision, photophobia, eye swelling, tear Crack，ect. The overall discomfort are evaluate by VAS . Uses a 100-mm line that is labeled at each end. 0 mm represents no eye discomfort, 100 mm represents the most intolerable eye discomfort. Patient will rate the VAS(average VAS in the past 24h three times a week).

Patients will rate their average eye comfort with VAS three times a week. The mean daily VAS over week 1-4 will be calculated as the sum of each day divided by the number of days assessed.

Check the tear break time(BUT) should be carried out before the other steps in the operation of the eye, used to evaluate the stability of the tear film. In the room without air flow, 1% of the sodium fluorescein with a glass rod dipped in a little coating in the lower eyelid conjunctival sac, the patient after several times, through the slit lamp cobalt blue light wide band inspection tear film, with a stopwatch Record the last time after the completion of the first blink of an eye to open to the tear film appeared in the first randomly distributed dry spots or black lines of time, recorded three times to take the mean.

Evaluation the tear secretion, do not use ocular surface anesthetic, measuring the amount of reflex tear secretion. Place the test paper in the middle and outer 1/3 of the conjunctiva of the lower eyelid, and instruct the patient to lighten his eyes or look down at the bottom, and remove it after 5 minutes to measure the wetness from the beginning of the bend.

Corneal fluorescein staining: 2% fluorescein sodium coated with glass rods in the conjunctival sac, observed under the slit lamp to observe whether the corneal epithelium with staining, such as yellow-green stained, suggesting that corneal epithelial cell integrity damage. Score by 12 points. Cornea was divided into 4 quadrants, each quadrant was 0-3, no staining was 0, 1 to 30 dotted was 1 point, > 30 dotted but not fused For 2 points, 3 points for the emergence of corneal punctate staining, filaments and ulcers.

This questionnaire includes three brief questions to investigate whether patients believe that moxibustion treatment will be useful. The relationship between patients' expectations and the effectiveness of moxibustion will be investigated because patients' beliefs about treatment enhanced or attenuated the effectiveness of treatment in a previous experimental study .