Dry eyes a one-slide talk? Drs Ma and Loveridge-Easther set the record straight from the start; it’s a complex problem and to leave it untreated invites trouble.
It’s a problem, Dr Loveridge-Easther says, that can start small but become very serious. He took the first half of the presentation to describe the problem. Dr Ma’s section talked about treatment.
Tears cleanse, lubricate, and nourish the eye’s surface and provide physical and immune protection against infection.
A small change in this film can cause significant changes to vision and lead to that burning, sandy feeling.
Ultimately, the changes can lead to permanent loss of vision in cases of severe dry eye.
The tear film consists of three distinct layers, produced by different glands around the surface of the eye and in the eyelids The tears increase if even slight damage is inflicted on the eye’s surface. The tears’ contents change to protect the wound. Blood vessels dilate, causing reddening of the eye. Everything works together to protect the eye.
It’s automatic – touch your eye and the process is poised to start healing any damage.
Your emotions can trigger tears too. Blinking, we do it 20 times a minute, smooths this tear film and disperses it evenly across the eye.
It all works well. But how does it go wrong? If you produce the wrong types of tears, they pour out and can damage the eye. The eye reacts to that damage by producing yet more tears, which compounds the problem.
The outer layer of the tear film is oily, to restrict evaporation. If the oily layer isn’t there, tears evaporate too quickly and become salty. The same thing happens if you can’t produce enough tears. The salt level begins to damage the eye.
“You start damaging the front of the eye. You start asking for more tears and the tears that get there to help out have increased salt, causing a vicious cycle of damage,” he says.
Sjögren’s
Sjögren’s brings a lot of these symptoms together. Sjögren’s is an auto-immune disease affecting moisture-producing glands and results in dry eyes and dry mouth. Dr Loveridge-Easther says there is primary and secondary Sjögren’s.
The first is straight-out Sjögren’s. Secondary means there’s also another connective tissue disease like scleroderma present: 13% of those with Sjögren’s have vision-threatening complications.
“You end with this cycle of toxic tears,” he says. “It causes damage but all you can send are more toxic tears.” As well as damage to the eye’s surface, the gland that produces the tears gets damaged too.
Treatment involves diagnosing the problem and working to break that cycle of damage.
Treatments
The treatment you receive for your auto immune disease has a beneficial effect of lessening the effects of secondary Sjögren’s, including dry eye, according to Dr Ma. She says, “Our objective of management is to improve your comfort, vision and your quality of life. Treatment depe
nds on the severity of dry eye and also the underlying cause.
1. Tear supplementation
Eye drops
All patients with dry eye require lubricant eye drops. This is used in conjunction with other treatments that may be required.
A wide variety of eye drops are available, and it may take trial and error until you find what works best for you. Eye drops with preservatives are available in multi-use bottles and are suitable for use up to 4 to 6 times a day. If using eye drops more than this, she recommends preservative-free eye drops. They’re costlier but they avoid the potential toxic effects of preservatives when overused. In particular, Dr Ma recommends against using any drops that contain benzalkonium chloride (BAK). Preservatives such as polyquad, sodium perborate and sodium chlorite are gentler on the corneal surface.
Gels and ointments
Lubricants also come in gel and ointment form. The advantage with this medium is longer-lasting action and therefore less frequent application required.
The trade-off is that gels and ointments will blur vision more than eye drops.
| Level | Symptoms | Signs | Treatments |
|---|---|---|---|
| 1 | Mild/episodic discomfort | Mild tear debris +/- lid disease | Education and environmental/dietary modifications. Elimination of offending systemic medications Artificial tear substitutes, gels, ointments Eyelid care and hygiene |
| 2 | Moderate/episodic discomfort Blur | +/- redness and corneal stain +/- lid disease | If level 1 treatments are inadequate, add: Anti-inflammatories Tetracyclines Punctal plugs Moisture chamber spectacles |
| 3 | Severe/frequent discomfort Chronic blur | Red Marked staining Tear debris Lid disease | If level 2 treatments are inadequate, add: Serum Contact lenses Permanent punctal occlusion |
| 4 | Severe/disabling constant discomfort Chronic blur | Red Severe staining Tear debris Ulceration Keratinization | If level 3 treatments are inadequate, add: Systemic anti-inflammatory agents Surgery (lid surgery, tarsorrhaphy, mucus membrane, salivary gland, amniotic membrane transplantation. |
Table shows an example of grading dry eye severity and the escalation of possible treatments
2. Tear retention
Occluding a passage of tear drainage can help retain tears around the eye for longer.
Punctal occlusion can be trialled with punctal plugs which can be made of permanent material such as silicone or hydrogel, or with temporary dissolving material such as collagen. More permanent measures such as punctal cautery can also be considered.
Moisture Chamber Spectacles work by increasing humidity of the eye and the thickness of the lipid layer of the tear film.
3. Tear stimulation
Secretogogues, (substances that enhance secretion) are under investigation for their use in dry eye. Pilocarpine is a systemic oral medication, which makes eyes water more.
However, it has unfavourable side effects like excessive sweating, blurred vision and headaches. In practice, these are seldom used, Dr Ma says.
4. Biological Tear Substitutes
Serum eye drops are effective in many ocular surface diseases, however they’re not suitable in use in dry eye disease associated with Sjögren’s.
5. Anti-Inflammatory Therapy
Anti- inflammatory medicines can help by reducing the inflammatory drive in the vicious cycle of dry eye and also improving the quality of tears.
Cyclosporine-A (Restasis) is a medication that helps the eye produce the maximal amount of tears it is capable of.
Corticosteroids (e.g. Fluorometholone) are effective at reducing inflammation however, they should be for short-term and supervised use because of other effects to the eye.
Tetracyclines (e.g. Doxycycline) are a class of antibiotic that stabilizes the lipid layer and improves tear quality.
6. Essential Fatty Acids
Omega-3 fatty acids have multiple health benefits. They improve the lipid layer of tears and reduce inflammation. They generally come in fish-oil tablets. Vegetarians can substitute flax-seed oil.
7. Environmental
Your environment may affect the condition of your eyes. Dr Ma says things like low-humidity air conditioning will dry your eyes. Some of your regular systemic medications may be doing so too. It is important also to make sure that the eyes are fully closed while sleeping.
If there is nocturnal eye opening, taping the eyelids shut may
stop moisture loss at night.
8. Surgery
In very severe cases of dry eye especially in those with resulting eye disease, surgical procedures may be indicated. Tarsorrhaphy is a surgical procedure in which the eyelids are partially sewn together to narrow the eyelid opening to prevent exposure and drying out of the eye.
There are other surgical procedures to improve tear retention and to fix ingrown lashes.
Dry eyes – certainly not a one-slide talk!