Schirmer’s test

Schirmer’s test is a measurement of tear production, devised by the German ophthalmologist Otto W.A. Schirmer. Originally, Schirmer used blotting paper to collect tears elicited by one of the 3 methods of stimulating lacrimation:

1. Inserting the strip of paper itself
2. Irritating the nasal mucosa after the cornea had been anesthetized
3. Having the patient look into the sun

Indication: Evaluation of dry eye (Measures aqueous tear production)

Mnemonic:

Test 1 measures 2 things.
Test 2 measures 1 thing.
Test 3 measures Nose thing.

Types:

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

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

2. Schirmer II (with anesthetic): measures baseline secretion

• function of accesory lacrimal glands (the basic secretors)

3. Schirmer III (without anesthetic): with nasal irritation

• nasal mucosal stimulation represents a maximal secretory stimulation for the lacrimal glands and can thus reveal the maximal secretory capacity of the lacrimal glands.

According to some authors: Schirmer I is divided into a. without anesthetic and b. with anesthetic. While Schirmer II represents test with nasal irritation.

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