Non-pharmacological Treatment

Non-pharmacological Treatment of Mild-to-Moderate DES

For patients with mild dry eye syndrome (DES), aqueous or lipid enhancement of the tear film with topical agents is the appropriate first-line therapy. These include emulsions, gels and ointments collectively known as artificial tears. Artificial tears are useful for both aqueous tear deficient dry eye (ADDE) (in which case they are fully aqueous) and evaporative dry eye (EDE) (in which case they are a lipid-containing emulsion). Most topical agents contain preservatives to prevent microbial contamination. Because preservatives can damage the ocular surface, artificial tears with preservatives should be administered a maximum of 4-6 times per day. Others (e.g., CEDARS) suggest using preserved drops no more than four times per day. More recently, preservative-free formulations have become available in bottles rather than just single use vials, making the use of preservative-free drops more available to patients. More viscous artificial tears are better in this regard because they require fewer daily applications but may result in blurred vision. In cases where a more frequent application is required, preservative-free agents are preferred. Currently available evidence suggests that there is little difference in efficacy among the various over the counter (OTC) preparations, including between preserved and preservative-free formulations. It should be noted that practical considerations such as the patient’s lifestyle and manual dexterity can act as important constraints on the use of artificial tears. Patients with mild EDE caused by Meibomian Gland Dysfunction (MGD) can also benefit from application of warm compresses to the eyes such as a warm, moist cloth, or a purpose-designed mask; this is intended to melt the secretions blocking the meibomian gland ducts in MGD. Although this method has established efficacy, compliance is frequently poor because of the required time and effort in maintaining the necessary temperature for duration of each application.

Several non-pharmacological options exist for the treatment of patients in whom tear film enhancement with topical agents and/or other initial strategies either fail or are impractical.

Punctal occlusion, i.e., blockage of the puncta (the openings through which tears are drained), represents one option for patients with ADDE. Punctal occlusion is typically achieved using punctal plugs, placed at the punctal opening or within the canaliculi (the channels through which the tears drain). Two types of plugs are available: absorbable, which are temporary (lasting a few weeks) plugs made of degradable material (e.g., collagen) and which are normally used to test the efficacy of occlusion and non-absorbable (or permanent) plugs, which are typically silicon-based and represent a more long-term solution. In patients who are unable to retain or tolerate punctal plugs, permanent surgical punctal occlusion may be considered (see the Treatment for Severe Disease subsection). Punctal plugs are generally effective at reducing dryness and some studies report better symptom improvement compared to artificial tears.

Nasal neurostimulation is another potentially useful option for patients with ADDE. It is based on the activation of the nasolacrimal reflex (NLR), which stimulates tear production in response to chemical or mechanical stimulation of the mucosa in the nose. Nasal neurostimulation is achieved with small, hand-held devices which the patient can use to self-deliver a small electrical current either intranasally (to the trigeminal nerve) or extranasally (to the external nasal nerve). Neurostimulation has demonstrated efficacy in promoting tear production and maintaining tear film stability but has not yet been widely adopted as a treatment for DES.

For patients with EDE, especially those frequently exposed to environments that promote tear evaporation (e.g., high-altitude mountain climbers, motorcyclists), moisture chamber glasses and other wearable devices that provide a humid environment which reduces airflow over the surface of the eyes may be useful. Humidifiers and other devices that enhance local air humidity may also be helpful.

Additional options for patients with EDE include intense pulsed light (IPL) therapy, vectored thermal pulsation treatment (VTPT), and intraductal meibomian gland probing. In IPL therapy for EDE, light (580-1200 nm in wavelength) is delivered in four pulses to the skin area immediately below the lower eyelid. While its mechanism of action in EDE treatment remains poorly understood, current evidence suggests that IPL improves tear film structure and may reduce DES symptoms, particularly when combined with manual expression (i.e., removal of the contents) of the meibomian glands. Vectored thermal pulse treatment is a method developed to overcome the difficulties with maintaining a constant temperature in warm compresses. In VTPT, an automated thermal pulsation device delivers warm compresses more precisely, with one part of the device providing heat to the meibomian glands and the other delivering mechanical stimulation to the eyelids, evacuating the contents of the meibomian glands in the upper and lower eyelids simultaneously. Compared to standard wet compresses, VTPT significantly improves tear film breakup time (TBUT) and DES symptoms. Finally, intraductal meibomian gland probing is a procedure which mechanically opens and dilates the orifice of the meibomian gland, removing any obstructing secretions. While several studies have reported its efficacy in the treatment of MGD, meibomian gland probing is an invasive procedure whose risks and benefits must be carefully weighed; it is best reserved for patients with refractive obstructive MGD.

The non-pharmacological options for the treatment of mild-to-moderate DES discussed above are summarized in Table 3-1.

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