THERE IS INCREASING awareness in the eyecare community of intense pulsated light (IPL) therapy for treating meibomian gland dysfunction (MGD), dry eye disease (DED), rosacea, and Demodex. The Tear Film & Ocular Surface Society Dry Eye Workshop II (TFOS DEWS II) categorizes IPL as a second line of treatment, following lifestyle changes, ocular lubricants, lid hygiene, and warm compresses (Jones et al, 2017).

An IPL device is not a laser. Rather, it emits broad spectrum high-intensity light in the range of 500nm to 1,200nm, and cut-off filters are used to achieve the appropriate wavelength depending on the tissue targeted for treatment, making IPL useful for a myriad of conditions. For DED, 500nm to 600nm wavelengths are used to target the chromophores in the melanin or blood (Toyos et al, 2015).

The light is absorbed by oxyhemoglobin, creating heat that coagulates the superficial blood vessels (telangiectasias) in the skin and eyelids (Raulin et al, 2003). This results in the dual outcome of both destroying vessels that perpetuate inflammation and decreasing proinflammatory mediators, which disrupts the inflammatory cascade that contributes to MGD (Bron et al, 2017).

Here are other ways in which IPL works:

1. Eradicating Demodex and reducing the bacterial load on the eyelids. The pigmented exoskeleton of Demodex contains a chromophore that absorbs IPL energy (Kirn, 2002). Histological studies have confirmed that IPL causes necrosis of Demodex (Fishman et al, 2020).

2. Stimulating fibroblast activity in the skin. Cells lay down new collagen, which has aesthetic benefits to the skin, especially for rosacea patients (Goldberg, 2012).

3. Decreasing overactive epithelial skin cell turnover. This turnover is common in rosacea and can lead to the accumulation of debris on the lid margin, which can obstruct the meibomian gland (MG) orifices (Dell, 2017).

4. Improving the composition of tear proteins and lipids by decreasing inflammatory interleukins in tears—IL-17A and IL-6—as well as matrix metalloproteinase-9 (MMP-9) (Liu et al, 2017). It improves the osmolarity of the tears.

5. Softening MG secretions as the light energy absorbed warms the skin and internal blood vessels, thereby facilitating expression of meibum (Choi et al, 2019). There is evidence on confocal microscopy studies that IPL improves the morphology of the MGs, which helps restore their function (Yin et al, 2018).

Patient candidacy is limited to those who have Fitzpatrick skin types I-IV (Sharma and Patel, 2022). The rule of thumb for best success is to perform a series of at least three to four treatments, sometimes more, depending on disease severity, at least three to five weeks apart. Six-month or annual maintenance treatments may be necessary for continued results, depending on the patient. The current literature also supports the synergistic effects of IPL and MG expression in combination (Shin et al, 2021).

There is no silver-bullet solution for treating DED/MGD, but IPL provides a unique treatment opportunity targeting various mechanisms of action. Not only does IPL improve MG function, stabilize the tear film, and decrease ocular surface inflammation, but it also improves meibum quality, lid margin normality, meibum expressibility, tear break-up time (TBUT), ocular surface staining, and the Ocular Surface Disease Index (OSDI) score (Rong et al, 2018). CLS

REFERENCES

1. Jones L, Downie LE, Korb D, et al. TFOS DEWS II Management and Therapy Report. Ocul Surf. 2017 Jul;15:575-628.
2. Toyos R, McGill W, Briscoe, D. Intense Pulsed Light Treatment for Dry Eye Disease Due to Meibomian Gland Dysfunction; A 3-Year Retrospective Study. Photomed Laser Surg. 2015 Jan;33:41-46.
3. Raulin C, Greve B, Grema H. IPL technology: a review. Lasers Surg Med. 2003;32(2):78-87.
4. Bron AJ, de Paiva CS, Chauhan SK, et al. TFOS DEWS II pathophysiology report. Ocul Surf. 2017 Jul;15:438–510.
5. Kirn T. Intense pulsed light eradicates Demodex mites. Skin Allergy News. 2002;33(1):37.
6. Fishman HA, Periman LA, Shah AA. Real-time video microscopy of in vitro demodex death by intense pulsed light. Photobiomod Photomed Laser Surg. 2020 Aug;38:472-476.
7. Goldberg D. Current trends in intense pulsed light. J Clin Aesthet Dermatol. 2012 Jun;5:45-53.
8. Dell SJ. Intense pulsed light for evaporative dry eye disease. Clin Ophthalmol. 2017 Jun;11:1167-1173.
9. Liu R, Rong B, Tu P, et al. Analysis of Cytokine Levels in Tears and Clinical Correlations After Intense Pulsed Light Treating Meibomian Gland Dysfunction. Am J Ophthalmol. 2017 Nov;183:81-90.
10. Choi M, Han SJ, Ji YW, et al. Meibum Expressibility Improvement as a Therapeutic Target of Intense Pulsed Light Treatment in Meibomian Gland Dysfunction and Its Association with Tear Inflammatory Cytokines. Sci Rep. 2019 May;9: 7648.
11. Yin Y, Liu N, Gong L, Song N. Changes in the Meibomian Gland After Exposure to Intense Pulsed Light in Meibomian Gland Dysfunction (MGD) Patients. Curr Eye Res. 2018 Mar;48:308-313.
12. Sharma AN, Patel BC. Laser Fitzpatrick Skin Type Recommendations. Stat Pearls. 2022 March.
13. Shin KY, Lim DH, Moon CH, Kim BJ, Chung TY. Intense pulsed light plus meibomian gland expression versus intense pulsed light alone for meibomian gland dysfunction: a randomized crossover study. PLoS One. 2021 Mar; 16:e0246245.
14. Rong B, Tang Y, Liu R, et al. Long-Term Effects of Intense Pulsed Light Combined with Meibomian Gland Expression in the Treatment of Meibomian Gland Dysfunction. Photomed Laser Surg. 2018 Oct;36:562-567.