What is it?
Mucus fishing is both something that patients do and a medical diagnosis. Patients with MFS literally ‘fish’ mucus out of their eyes with their finger, a tissue, cotton bud etc.
Why does it occur?
In most cases a past or ongoing disease triggers excess mucus production. Common causes include dry eye, viral and allergic conjunctivitis, blepharitis and pterygium. For whatever reason the eyes produce more mucus and patients naturally clean it away. Unfortunately touching the very sensitive tissues on the surface of the eye or inside of the eyelid causes more inflammation and greater mucus production. Even if the original problem goes away a vicious cycle of mucus production and fishing continues.
What do patients notice?
The most common complaint is the presence of stringy mucus that gathers inside the lower eyelid, sticks to the surface of the eye and covers the cornea interfering with vision. Some patients also complain of irritable, red and itchy eyes.
How is it diagnosed?
Occasionally patients report what they are doing, making the diagnosis easy. Others are not aware of their actions and some are embarrassed to tell their story. It is important that optometrists and ophthalmologists think about the condition, especially when they observe excess mucus in the tears.
The best way to diagnose MFS is to ask patients to show you exactly what they do to clean their eyes. If their finger or a tissue touches the surface of the eye or the inside of the eyelid the diagnosis is clear.
To cure MFS it is important to:
- Stop fishing
- Reduce inflammation
- Break up the mucus
- Treat underlying conditions
The key to successful treatment is for patients to never touch the white of their eyes or the inner surface of their eyelids with anything. This can be difficult as the habit may be hard to break and initially there will be increased mucus in the eye. Some patients find that they need something to remind them not to touch their eyes. Successful strategies include wearing sunglasses, swimming goggles and gloves. Nail extensions have been known to help! It is best to plan to stop fishing at a time when you are likely to be distracted by other things such as gardening or sport.
Management of inflammation
Excess mucus production occurs because the eye and eyelid are inflamed. Treating inflammation makes it much easier for patients to stop fishing. Useful strategies include:
- Cold compresses
- Rinsing the eye with refrigerated artificial tears
- A short course of non-preserved steroid eye drops
Break up mucus
The mucolytic drug n-acetylcysteine can be very helpful.
Treat underlying conditions
The commonest causes of MFS that require ongoing management are allergy and dry eye. Treatment with anti-allergy drops such as sodium cromoglycate and non-preserved artificial tears may be necessary.
The good news
In almost every case mucus production will resolve within two weeks as long as the fishing stops.