Wednesday, September 9, 2015

Grant Watters on 'Meibomian Gland Dysfunction and Contact Lenses'

Grant Watters latest article on “Meibomian Gland Dysfunction and Contact Lenses” in the latest issue of N.Z.Optics.

Also referred to in the latest issue of N.Z.Optics is  the latest treatment technology for Dry Eye, IPL (intense pulsed light) which Mortimer Hirst will be launching in October.


Meibomian gland dysfunction and contact lenses: our challenge

BY GRANT WATTERS*

Awareness of meibomian gland dysfunction (MGD)—and its role in ocular surface discomfort and contact lens intolerance—has been raised by the Tear Film and Ocular Surface Society (TFOS) workshop. Working towards understanding the mechanisms contributing to MGD and the implications of MGD on ocular surface health, the TFOS came up with a definition of MGD: 

MGD is a chronic, diffuse abnormality of the meibomian glands, commonly characterised by terminal duct obstruction and/or qualitative/quantitative changes in the glandular secretion. It may result in alteration of the tear film, symptoms of eye irritation, clinically apparent inflammation, and ocular surface disease.

Because it is well established that all types of contact lenses (CL) can disrupt the lipid layer of the tears, it stands to reason that any MGD will exacerbate the situation, and cause an increase in evaporative dry eye and contact lens intolerance. Add to this the “hostile” environment of air conditioned offices, heating in cars and at home, and a lowered blink rate during long hours of computer work and you end up with a surprising number of patients struggling, especially with the added “double whammy” of impending presbyopia.

These “Peter Pan Presbyopes” want solutions. Their eyes are drying out, causing blurred vision, and their near focus is also deteriorating. CL technologies for presbyopia can still be limiting, especially as we absolutely require wettable CL materials with good stable optics. A bridge too far? 

To provide some sort of a solution in our practice, we have become more assertive in offering in-house MGD therapy. We recommend the purchase of an eye wheat bag to replace the use of facecloths at home for more sustained heat release and for longer heat exposure periods of four to five minutes. We perform regular in-house expression programmes: first with eye wheat bags to warm up the MG’s; then, a golf club spud for lid margin debridement of any keratin over the MG’s; and finally with MG expression using mastrota paddle tweezers. We are also considering buying an E>EYE IPL machine, which has shown great promise (see separate story). The problem is that MGD, like blepharitis, can be chronic and recurrent—two ominous words—and patients are time-poor and even lazy when it comes to doing their own home therapy. Usually when things are going better, patients tend to stop doing their home treatments and then of course things take a turn for the worse. Educating them is therefore key so they know how to get back on track.

In-house MGD therapy actually achieves two things: you motivate the patient into keeping it up and you give them a “head start” for their home sessions; plus it allows you to diagnose far more accurately the degree or grade of blockage. Are the ducts completely plugged? Or, if expressible, what is the texture and colour like? Is it cloudy or creamy like tooth-paste or fairly clear? Does the patient show improvement with time? Are the lid margins looking less red and inflamed? Is there any improvement in corneal staining? I tell patients that one session in-house is the equivalent of them doing it for about two weeks at home to help motivate them.

If after a month of weekly in-house and home sessions there is little or no improvement, I write to the patient’s GP to ask for additional oral doxycycline or azithromycin supply, explaining why. Most GP’s will send out a script without insisting on a consultation and the mucolytic effect of tetracyclines can often soften up the blockages, improving treatment outcomes.

With a bit of effort and teamwork from us and the (motivated) patient, we can usually make good progress. Keeping them on an on-going home maintenance programme of eye wheat bag warm compresses and digital massage for 2-3 sessions a week also seems to help avoid regression.

Finally, there are two other groups of CL wearers who have to have a good stable tear film: orthokeratology (OK) wearers and keratoconics. The hydraulic engineering the tear film must achieve in OK lens wearers is massively affected by marginally dry eyes. While a lot of keratoconics have little choice other than to tolerate CLs for at least 16 hours a day in all sorts of crazy conditions. I have had to “pre-treat” OK children for MGD before proceeding, as it’s much easier to do first than having to backtrack! It is also not unusual for OK kids and keratoconics to have rosacea which has been overlooked. Also do a little bit of investigative work to see if any of your teenage OK wearers are on Roaccutane? Plus, MGD is known to be more prevalent in the Asian population.

In general we need to be more attentive to MGD therapy to help our CL patients maintain asymptomatic wear for reasonable periods. Our patients certainly enjoy their in-house “day spa” sessions and get on board with some positive education, after all “a problem shared is a problem halved!”

* Grant Watters is a qualified TPA optometrist and co-owner of Mortimer Hirst in Auckland. He specialises in keratoconus, Ortho-K (orthokeratology), complex contact lens fitting and management and contact lens troubleshooting. He’s also a lecturer and researcher with the Departments of Optometry and Vision Science and Ophthalmology, University of Auckland.

REFERENCES:
• Craig JP, Chen Y-H, Turnbull PRK. Prospective trial of intense pulsed light for the treatment of meibomian gland dysfunction. Invest Ophthal Vis Sci 2015; 56(3):1965-1970.
• Nichols KK et al. The International Workshop on Meibomian Gland Dysfunction: Executive Summary. Invest Ophthal Vis Sci 2011; 52(4):1922-1929.
• Pult H, Riede-Pult BH, Nichols JJ. Relation Between Upper and Lower Lids’ Meibomian Gland Morphology, Tear Film, and Dry Eye. Optom Vis Sci 2012; 89(3):310-315.
• Kunnen C, Nichols JJ. Meibomian Gland Dysfunction: An Update. CL Spectrum 2015; 30:22-27.
• Efron N. Contact Lens Complications (3rd.Ed) 2012 Elsevier.


Dry Eye Treatment*

E>Eye gets the thumbs up in latest NZ patient research

More than 80 per cent of patients who received E>Eye intense pulsed light (IPL) treatments at Merivale Optical in Christchurch reported their dry eye symptoms had improved, while 95.7 per cent said they would recommend the treatment to others.

The results come as part of a survey of E>Eye patients at Merivale treated over a 10-month period. Of the 86 respondents, 74.4 per cent were over 60 years old, 23.3 per cent were between 20 and 40 years old and 2.3 per cent were between 20 and 40. The research was conducted by John Veale, optometrist at Merivale and New Zealand distributor for France Medical’s E>Eye machine.

The E>Eye machine has been specifically designed for treating dry eye due to meibomian gland dysfunction (MGD). The device works by producing a calibrated series of IPL. These light pulses are precisely set at a specific energy and frequency to stimulate the meibomian glands and help them to recover their function.

Other results from Merivale’s research include 98.5 per cent saying the treatment was “no problem” or “okay”, and 55 per cent reporting they no longer needed to use eye drops following treatment.

A double-blind, placebo-controlled clinical trial of 28 patients with MGD by Associate Professor Jennifer Craig from the Ocular Surface Laboratory in Auckland University’s Department of Ophthalmology found 82 per cent of patients showed improvement after three treatments with the E>Eye device of at least one lipid layer grade on day one with 86 per cent noting reduced symptoms by day 45. There was also significant improvement in non-invasive tear breakup time (NIBUT) vs controls*.

For more information on the E>Eye visit: www.dryeyetreatment.co.nz. 

*Source: Craig, Jennifer P., Yen-Heng Chen, and Philip RK Turnbull. “Prospective trial of intense pulsed light for the treatment of meibomian gland dysfunction.” Investigative ophthalmology & visual science 56, no. 3 (2015): 1965-1970.

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