D - Dry Eye - Week 1 redone

Question 1

What is the 2017 TFOS DEWS II definition of dry eye?

Answer 1

A multifactorial disease of the ocular surface characterised by a loss of homeostasis of the tear film, and accompanied by ocular symptoms, in which tear film instability and hyperosmolarity, ocular surface inflammation and damage, and neurosensory abnormalities play aetiological roles

Question 2

In regards to dry eye: how do you manage signs without symptoms?

Answer 2

Preventative management as appropriate (e.g. pre-surgery)

Question 3

How do you manage neurotrophic conditions (dysfunctional sensation)?

Answer 3

Signs indicate management of DED is required

Question 4

How do you manage a patient with dry eye symptoms but it’s another ocular surface disease?

Answer 4

Refer/manage according to differential diaignosis

Question 5

How do you manage symptoms without signs/pre-clinical state?

Answer 5

Observe/offer education/preventative therapy

Question 6

How do you manage dry eye patients with no signs and neurotrophic pain?

Answer 6

Refer for pain management

Question 7

Provide an example how a patient can have signs of dry eye but no symptoms

Answer 7

Nerve damage causing loss of sensation

Question 8

What is the lacrimal functional unit comprised of?

Answer 8

Lacrimal gland, ocular surface components, MGs, eyelids, assoc. sensory (CNV) and autonomic (CNVII) innervatino

Question 9

What does the lacrimal functional unit regulate? (3)

Answer 9

Tear secretion
Tear distribution
Tear clearance

Question 10

What can disruption to one or more components of the lacrimal functional unit lead to?

Answer 10

Loss of tear film homeostasis

Question 11

From where does the cornea receive sensory input?

Answer 11

From the ophthalmic division of the trigeminal nerve

Question 12

Is staining enough to diagnose dry eye?

Answer 12

No

Question 13

What is the difference between nociceptive pain and neuropathic pain?

Answer 13

Nociceptive: pain in response to actual or threatened tissue damage

Neuropathic: pain in response to damage to the somatosensory pathway

Question 14

Which is more transient: nociceptive pain or neuropathic pain?

Answer 14

Nociceptive (whereas neuropathici is more chronic)

Question 15

Which type of pain activates the corneal nerves? Nociceptive or Neuropathic?

Answer 15

Nociceptive

Question 16

Is topical treatment that useful in treating neuropathic pain?

Answer 16

Not really, since it’s higher up

Question 17

List features of clinical history that would make you suspect neuropathic pain (2)

Answer 17

Heat or prickling sensation
Association with other neuropathic disorders (e.g. migraine)

Question 18

How can you anatomically evaluate corneal

Answer 18

Corneal confocal microscopy

Question 19

What functional test can you do for corneal neuropathy? What outcome would indicate neuropathy?

Answer 19

Test central sensitisation with either topical anaesthetic or sclerlal lenses. if level of pain stays the same, then it’s neuropathic

Question 20

List the 3 steps in the diagnostic algorithm for dry eye

Answer 20

Triaging questions
Risk factor analysis
Diagnostic tests

Question 21

What are the 4 most important trading questions for dry eye?

Answer 21

Any mouth dryness or swollen glands?
Vision affected? Does it clear on blinking?
Itchy/swollen/crusty on waking/any discharge?
Have you been diagnosed with any general health conditions?

Question 22

List 5 other important triaging questions for dry eye

Answer 22

How severe is the discomfort?
How long have your symptoms lasted and was there any triggering event??
Are the symptoms or redness worse in one eye than the other?
Do you wear contact lenses?
Are you taking any medications?

Question 23

List 4 non-modifiable risk factors for dry eye?

Answer 23

Age > 40yo
Female
Asian
Systemic (DM, rosacea, rheumatoid, sjogren’s, thyroid)

Question 24

List 5 modifiable risk factors for dry eye

Answer 24

Meds
Smoking
VDU
Contact lens
Environmental factors (humidity, air currents/drafts/air conditioning)

Question 25

What screening test is used for dry eye? What values do we expect for dry eye?

Answer 25

Questionnaire: Either OSDI >/= 13 or DEQ-5 >/= 6

Question 26

Describe the order of homeostasisi marker tests for dry eye while providing their normal values

Answer 26

1. NIBUT (<10 sec = dry eye) 2. Osmolarity (>308mOsm/L or interocular difference >8 = dry eye) 3. TBUT (<10 sec = dry eye) 4. Ocular surface staining (>5 corneal spots; >9 conj spots; or lid margin >/= 2mm length & >/= 25% width) NB: pick one of TBUT and NIBUT. Also sometimes osmolarity isn’t available in clinic etc. Also should find out how to do osmolarity

Question 27

What does a score of >/= 12 on DEQ-5 indicate?

Answer 27

Possible sjogren’s

Question 28

Where is NIBUT performed? How many measures do you take?

Answer 28

Performed on topographer (observe the quality of the motors over time). Take the average of 3 measures

Question 29

What happens to the results of osmolarity if you accidentally poke the patient in the eye?

Answer 29

Patient will get hyposmolarity so it will look like their osmolarity reading is lower than it actually is. This is due to reflex tearing from being poked in the eye

Question 30

What are the key parameters to look at in meibomian gland evaluation? (3)

Answer 30

Evaluate lid margin Express MGs Examine secretion colour and consistency

Question 31

How is the MGS (Meibomian Glands yielding liquid Secretion score) assessed? What score is classified as clinically significant MGD?

Answer 31

Express 5 glands inferiorly (5 nasal, 5 central, 5 temporal). Score is as follows: 3 = clear liquid secretion 2 = cloudy liquid secretion 1 = toothpaste consistency 0 = no secretion MGS < 12 = clinically significant MGD

Question 32

What does Meibography assess?

Answer 32

Extent of drop out as a percentage of the eyelid (loss of secretory acinar tissue)

Question 33

Is tear meniscus height a reliable parameter for dry eye assessment?

Answer 33

Not particularly, too variable

Question 34

What happens if you use too bright a light when measuring tear meniscus height?

Answer 34

Reflex tearing will make the meniscus height larger

Question 35

When should you expect dry eye when doing the phenol red test? (Values wise)

Answer 35

<10mm/15sec

Question 36

When should you expect dry eye/sjogren’s in the schooner test?

Answer 36

<5mm/5min