Precorneal Tear Film Part 2 - Clinical Evaluation of Tear Film Answers

If a patient comes into your practice complaining of excessive tearing what are the initial things you should evaluate to see if the patient has a “wet eye” versus” dry eye”.

1. find out if the complaints are in one eye or both

2. determine if the pt has allergies, meds, or systmeic diseases that all could cause dry eye or cause eyes to tear

Describe the tests to evaluate a “wet eye” or a patient with epiphora: fluorescein disappearance test

– instill dye in patient’s eye and observe tear meniscus become clear

Describe the tests to evaluate a “wet eye” or a patient with epiphora: primary jones test

instill fluorescein dye into patient eye and recover it from inferior meatus of the nose

Describe the tests to evaluate a “wet eye” or a patient with epiphora: Secondary Jones Test

dilate puncta and inject saline into nasolacrimal system with blunt needle

Describe the tests to evaluate a “wet eye” or a patient with epiphora: modified hones test

– instill fluorescein dye into patient’s eye and have patient blow nose to recover dye

symptoms of dry eye

tearing, burning, foreign body sensation, blurred vision and mild itching

Describe the tests to directly evaluate the quantity of tears which include the following: Schirmer #1 without anesthetic

tests for reflex tearing and basal tearing

Describe the tests to directly evaluate the quantity of tears which include the following: Schirmer #1 with anesthetic

tests for basal tearing

Describe the tests to directly evaluate the quantity of tears which include the following: Schirmer #2 – anesthetic

– irritate nose to stimulate tearing – never done

Describe the tests to directly evaluate the quantity of tears which include the following: Phenol Red Thread Test –

basal tearing

what dyes are used to evaluate dry eye

Rose Bengal and Lissamine Green – stains devitalized cells

Fluorescein stain – stains breaks in epithelium

Discuss the tests used to evaluate the stability of the tear film: non invasive BUT

keratometer and keratography

observe the mires from each instrument and count the # of seconds it takes for the mires to break up

Discuss the tests used to evaluate the stability of the tear film: tear BUT

1. instill fluorescein into the pt eye and observe w cobalt blue filter and count the # of seconds it takes for dry spot to appear

2. any time less than 10 sec is clinically significant

Describe how the Lactoferrin test are performed and how this evaluates lacrimal gland function.

Since lacrimal gland produces this protein (lactoferrin), the level of this protein can indirectly test the function of the lacrimal gland.

Lactoferrin micro assay tests test for lactoferrin protein.

Describe what the InflammaDry test measures?

measures levels of MMP-9 (protease released by damaged corneal epithelial cells) Marker for later DED.

Need to have epithelial damage for increased MMP-9 levels

Describe how to measure tear film osmolarity. What is the normal tear film osmolarity value?

Normal tear film osmolarity is 302mmol/kg.

Sample is taken from inferior tear meniscus.

Describe Meibography

Special imaging of Meibomian glands.

Can check for change in Meibomian gland morphology

Be familiar with the two major classifications of Dry Eye by the International Dry Eye Workshop (DEWS II):

Aqueous Deficient Dry Eye and Evaporative Dry Eye

List all the names for dry eye syndrome.

Dry eye syndrome

Ocular surface disease

Keratoconjunctivitis sicca

Dysfunctional tear syndrome

What causes Dry Eye in Menopausal Women

Estrogen and Androgen deficiency – reduces lacrimal gland and meibomian gland output

Discuss Sjogren’s Syndrome.

Autoimmune disorder that results in dry eye, dry mouth and arthritis.

Lymphocytes attack lacrimal glands, salivary glands, blood vessels of body and connective tissue (joints).

. Discuss evaporative dry eye as it relates to altered lipid chemistry. Note the importance of diagnosis of meibomianitis and blepharitis.

• Meibomian gland dysfunction is the most common cause of evaporative dry eye.

• This results in an abnormal lipid layer and excessive evaporation of the tear film, reduced TBUT and patients develop dry eye.

• Blepharitis is also common in these patients.

  • The bacteria that causes the blepharitis alters the lipid layer of the tear film.

Discuss evaporative dry eye as it relates to lid surface abnormalities

If there is improper or abnormal eye lid functioning, there is abnormal resurfacing of the tear film.

These can include paresis of CN VII, an abnormal attachment of the palpebral and bulbar conjunctiva (symblepharon) or a rolling in (entropion) or rolling out (ectropion) of the eyelid – to name a few.