OA Corner Part 15: Dry eye disease
The optical assistant (OA) is often the first point of contact for a patient who has contacted the practice with a problem with their eyes.
Although it is not the role of an OA to diagnose, it can be helpful to have some knowledge of the more common eye conditions encountered. This month we will look at dry eye disease (DED).
Types of DED
There are two main types of DED: 1) Evaporative dry eye, where the tears aren’t necessarily of the right quality to lubricate the eye; and 2) aqueous deficient dry eye where the volume of tears is lower than needed.
‘Mixed dry eye’ is often seen, which is a combination of both of the above. In recommending treatment for DED, it is important to know what type you are dealing with.
Signs and symptoms
DED is quite common, especially after the age of 50. Many practices have seen an increase in patients presenting with dry eye since lockdown, and this could be due to more patients working from home and spending longer in front of computer screens. It may also be due to the wearing of face masks, which can reduce air flow around the eyes.
Other factors that can contribute to dry eye are contact lenses, medications, air conditioning, central heating and even tiredness and stress. Patients often complain their eyes feel sore and gritty, and their vision can be intermittently blurred. They may be more prone to eye infections, and there is the potential for damage to occur to the corneal surface.
Contact lens wearers may find their contact lenses are uncomfortable, and their wearing time is reduced. Sometimes the eyes water, which is a reaction to the dryness, and the eyes produce excess tears to try to compensate. These tears tend to be too watery and, hence, overflow the lid margins. So watery eyes can be a sign of dry eye.
Management options
Encourage patients to employ the 20-20 rule
Management of DED often occurs in practice. Lubricating eyedrops in the form of artificial tears can be used. Many of these eyedrops are preservative free, which eliminates the possibility of the patient developing an allergic reaction to the preservatives, although this is rare with modern preservatives. Some eye drops have a watery consistency and can be used as frequently as the patient needs them.
There are also gels and ointments available. These are thicker than the drops, and so lubricate the eye for longer. They can be sticky, and may blur the vision for a while, and so some are often best used at night whilst asleep.
Meibomian gland dysfunction can also cause a dry and gritty eye sensation. The meibomian glands are tiny secreting glands in the lids that secrete an oily substance into the tears, which prevents the watery portion of the tears from evaporating. These tiny glands can become clogged, which prevents the oil from being released.
There are now products on the market similar to sleep masks, which are heated in a microwave, applied to the eyes and which can be helpful in unblocking these glands. The warmed mask is placed on the closed lids for 1o to 15 minutes following the manufacturer’s instructions carefully. This gentle heat causes the glands to release the oil into the tears. A good analogy is warming solid butter, causing it to become liquid.
Advice for patients with DED includes taking regular breaks when using a computer screen. The 20-20 rule is to look away from the screen every 20 minutes for 20 seconds. A humidifier can help to stop the air from becoming too dry and ensuring hydration levels are kept up by drinking water during the day can help. It is also important that contact lens wearers do not overwear their lenses, so ensuring contact lens patients have a back-up pair of specs is important too.
If the dry eye is severe, it may be necessary to refer the patient to a DED specialist. There are dispensing opticians and contact lens opticians who have undertaken extra training and accreditation to help DED patients and, in very severe cases, a referral to the eye hospital may be required as there are surgical options available for some patients. However, most case can be managed in practice.
For an accurate diagnosis, the patient will need to be booked in for an assessment to assess what type of DEE they are suffering with – and to rule out any other underlying conditions. However, it is useful for the OA to have some understanding of the signs and symptoms of dry eye disease.
A useful resource is the new Focus on Dry Eye Disease section on the ABDO Clinical Hub, which goes into more detail about this condition and how it can be managed.
Sue Deal FBDO R is a practising dispensing optician, ABDO College examiner, senior tutor and supervisor for dispensing opticians. She is also a practice visitor and external moderator for ABDO. She was recently awarded the ABDO Medal of Excellence for her outstanding services to the profession.
Links to Parts 1-12 can be found here.