Dry eye disease (DED) can be frustrating for both the clinician and the patient. Signs and symptoms tend not to correlate, and the pathophysiology is not always well understood.
In recent years, several new devices have emerged to aid in the management of this complex condition. Many of the devices focus on the lid margin and meibomian glands. In particular, they act by heating the meibum in the meibomian glands to facilitate expression. Lemp et al demonstrated in their 2012 Cornea study that 86% of dry eye patients have an evaporative component, so the lid margins seems to be a logical target. Other devices use different mechanisms and are also effective DED treatments.
This article will discuss the latest technology available to treat DED.
NEW TECHNOLOGY
LipiFlow
The LipiFlow device (Johnson & Johnson Vision) incorporates a shell applied to the front and back of the lids, attached to a heating unit. LipiFlow uses thermal pulsation technology to heat the lid margins (108 degrees), soften the meibum in the meibomian glands then express the material using pulsation of the shell.
Mibo Thermoflo
The Mibo Thermoflo device (Mibo Medical Group) is a probe applied to the eyelids. The probe applies heat (108 degrees) with gentle massage to the lids to soften and express meibomian material.
EyeXpress
The EyeXpress device (Holbar Medical Products) is a heat mask with a soft gel insert attached to a heating device. The mask is applied to the anterior surface of the patient’s lids and heated to 110 degrees to soften the meibomian material. Then, the clinician manually expresses material from the glands at the slit lamp.
iLux
The iLux device (Alcon) is a handheld instrument that uses light energy to heat the lid margins and soften the meibum. Then, under magnification and direct visualization, the clinician can apply compression to various locations on the lids to express the meibum.
TearCare
The TearCare system (Sight Sciences) is a wearable technology that applies heat to the anterior surface of the lids. Patients keep their eyes open during the procedure and can maintain blink function. This allows them to continue to express meibum during the procedure while the lids are heated. Once the treatment is complete, the clinician may further express meibum with the clearing instrument provided with each device.
Intense pulsed light
IPL (Lumenis) is designed to apply short bursts of light to the lids, causing changes in the blood vessels and increasing the temperature of the skin. This leads to softening of the meibum for expression, whether manually by the clinician or naturally by ordinary blinking.
BlephEx
The BlephEx device (Rysurg) is a handheld instrument with a spinning microsponge used to clean debris from the lashes and lid margin. Unlike the previously mentioned devices, this does not aim to heat the meibum. Rather, this device is designed to remove irritating debris from the lid margin while also removing the inflammatory biofilm that may obstruct the meibomian gland orifices.
NuLids
The NuLids system (NuSight Medical) is a heldheld device that patients may use at home to stimulate and decap the meibomian glands.
TrueTear
While each of the devices listed above attempt to treat the lid margin source, TrueTear (Allergan) takes a different approach.
This handheld device is used by the patient to increase tear production via nasal neurostimulation. The patient inserts the device tips into the nose to trigger the nasolacrimal reflex by stimulating the ophthalmic branch of the trigeminal nerve, leading to increased tear production. This device has been shown to increase mucus, aqueous and lipid layer production.
Home heat masks
Many available masks may be heated and applied to the eyes at home, with the goal of softening the meibum for improved expression with blinking.
THE TREATMENT ALGORITHM
Proper diagnosis aids a targeted approach
While multiple DED treatment options are available, it is important to use these in a targeted fashion rather than a shotgun approach. Before any treatment is initiated, the proper diagnosis must be made.
The Cornea, External Disease and Refractive Surgery Society, or CEDARS, dysfunctional tear syndrome algorithm divides DED into four categories: aqueous deficiency, evaporative dry eye secondary to goblet cell disease, meibomitis, blepharitis (with or without evaporative disease) and exposure. In addition, a fifth category is used: the co-conspirators. These are conditions that mimic or exacerbate DED, such as superior limbic keratoconjunctivitis, contact lens-related toxicity, mucous fishing syndrome, chemical toxicity, allergic/atopic keratoconjunctivitis, floppy lid syndrome and conjunctivochalasis. While these are distinct entities, they often coexist.
Targeting therapy toward the underlying diagnosis is essential for best results.
Look for lid margin disease
Most of the devices listed above are focused on lid margin disease and have the best effect for these patients. Among the clinical signs evident with lid margin disease are lid margin erythema, debris in lashes, collarettes, scurf, cylindrical sleeves, thickening and clouding of meibomian secretions and plugging of the meibomian orifices. Another finding often present with lid margin disease is a rapid tear break-up time (less than 10 seconds), indicating evaporative dry eye. More sophisticated testing, such as meibography, may demonstrate atrophy, dilation and drop out of meibomian glands within the lid.
Initial management
Typically, management of lid margin disease may start with warm compress, lid hygiene, antibiotic drops or ointment, steroid drops or ointments and omega-3 supplements. While these treatments are frequently quite effective, they are not always sufficient.
For patients who have significant debris on the lid margin, particularly with the build up of a biofilm along the margin, debridement of the lid margins may be quite effective. This can be done as an in-office treatment with a device such as Blephex, or as an at-home treatment with a device such as NuLids. Home heat masks, such as the Bruder mask, may also be effective.
To soften the meibum and facilitate expression, LipiFlow, Mibo Thermoflo, EyeXpress, iLux, TearCare and IPL may be beneficial. Patients with lid margin disease could be considered for any of the therapies. Due to the lack of insurance coverage, these treatments may be costly to the patient, so many patients may not wish to proceed immediately. Unfortunately, as the meibum continues to thicken, the glands may eventually atrophy beyond the point of no return, so it is essential that patients know they should not to wait too long to proceed with treatment.
These treatments tend to be most well received in patients in which the lid margin disease is also associated with DED (typically evaporative). The effect may also be enhanced if the lid margins are pretreated with a debridement procedure.
Aqueous tear-deficient dry eye
Successful treatment with these lid margin diseases theoretically would improve the evaporative component to dry eyes. Some patients may also have an aqueous-deficient component. This may be identified by either a decreased tear meniscus, low Schirmer score or corneal/conjunctival staining patterns.
Most of these patients are typically initially treated with topical therapies, such as lubricant drops or ointments, anti-inflammatory drops (lifitegrast [Xiidra, Shire], cyclosporine [Restasis, Allergan] and steroids) or punctal plugs. Occasionally, compounded medications, such as autologous serum tears or amniotic membrane extract, among other therapies, may be required.
For these patients, neurostimulation (TrueTear) may also be effective. This can be particularly useful for patients who cannot place or tolerate drops in their eyes. Interestingly, this treatment has been found to increase not just aqueous production but also mucus and lipid production.
Conclusion
DED is a complex progressive condition that may be difficult to treat due to its varying presentations and underlying etiologies. New treatments, both pharmacologic and procedural, are now available. With careful examination, the underlying diagnoses may be identified, and optimal, targeted treatments may be employed. OM