Indication: Evaluation of Dry Eye (Measures aqueous tear production)

Types:
1. Schirmer 1 (without anesthetic): measures baseline and reflex secretion

• function of main lacrimal gland, whose secretory activity is stimulated by the irritating nature of filter paper

2. Schirmer 2 (without anesthetic): measures baseline secretion

• function of accesory lacrimal glands (the basic secretors)

Materials required: 5 X 35 mm of Schirmer's strip or Whatman filter paper no. 41

Procedure:

1. The eye is gently dried of excess tears
2. The schirmer strip is folded 5 mm from one end and kept in the lower fornix at the junction of lateral 1/3 and medial 2/3 (do not touch cornea or lashes)
3. The patient is asked to close the eyes.
4. Tears in the conjunctival sac will cause progressive wetting of the paper strip.
5. After 5 minutes, the filter paper is removed and the distance between the leading edge of wetness and the initial fold is measured, using a millimeter ruler.

Interpretation:
Normal: >15 mm
Mild-moderate Keratoconjunctivitis sicca (KCS): 5-10 mm
Severe KCS: <5 mm

<10 mm is considered abnormal in Schirmer 1 and < 5 mm in Schirmer 2

Causes of KCS:

1. Idiopathic
2. Congenial alacimia
3. Xerophthalmia
4. Lacrimal gland ablation
5. Sensory denervation
6. Collagen vascular disease: Sjogren syndrome, SLE, RA