Doe IPL work for Dry Eyes? What is Intense Pulse Light?

A good article below just came out to show the positive effect of IPL for Dry Eyes.
We have known this for years, but it is good to have more published studies to confirm our clinical findings. 

The key points are the following:

1. Intense Pulse Light (IPL) is an intense pulse of noncoherent polychromatic light with a broad wavelength spectrum of 500–1200 nm.
Vora GK, Gupta PK. Intense pulsed light therapy for the treatment of evaporative dry eye disease. Curr Opin Ophthalmol. 2015;26(4):314–18. doi:10.1097/ICU.0000000000000166.[Crossref], [PubMed], [Web of Science ®], [Google Scholar]

2. Patients who should not have IPL:
a. those with excessive sun exposure in previous 1 month
b. dark skin types (ie, skin Fitzpatrick scale V/VI)
c. history of herpes zoster infection
d. women who are pregnancy, 
e. patients using photosensitive drugs/foods

3. Compared to routine eyelid lygiene for MGD, IPL treatment is more time-efficient and has better efficacy, lasting more than 6 months.2


Vora GK, Gupta PK. Intense pulsed light therapy for the treatment of evaporative dry eye disease. Curr Opin Ophthalmol. 2015;26(4):314–18. doi:10.1097/ICU.0000000000000166.[Crossref], [PubMed], [Web of Science ®], [Google Scholar] 
4. IPL works to improve Dry Eye by treating Meibomian Gland Dysfunction (MGD) through it photothermal, photomodualtion, anti-inflammatory effects: [meaning the intense light provides direct energy to the glands to dilate them and help liquify the oil (to become more like warm coconut oil/olive oil than cold oil) and help move the oil out with expression & the light directly decreases inflammatory cell action].
5. The study below shows histological proof of the effect of IPL. Further cytological and molecular studies are are still needed to prove exactly how IPL works. 



References:

1.

Current Eye Research 

Changes in the Meibomian Gland After Exposure to Intense Pulsed Light in Meibomian Gland Dysfunction (MGD) Patients

Yue Yin,Ninghua Liu,Lan Gong &Nan Song

ABSTRACT

Purpose: To observe (1) changes in meibomian gland (MG) after exposure to intense pulsed light (IPL) and (2) to understand the mechanism by which IPL treats meibomian gland dysfunction (MGD) in patients.

Methods: A cohort study, including 35 MGD patients, was conducted. IPL treatment was administered in one group (IPL group; n = 18), and eyelid hygiene in another (control group; n = 17) for 3 months. All patients were given artificial tears during the treatment period. Associated ocular-surface indexes (ocular surface disease index, OSDI; tear breakup time, TBUT, Schirmer 1Test, corneal staining, and conjunctival staining), MG function, MG macro-morphology, and MG micro-morphology were examined before and after treatment. The relationships between the change in symptom score and the change in the other indexes (related ocular-surface indexes, MG functional indexes, and MG morphological indexes) were evaluated.

Results: There was no statistical difference in pretreatment between the IPL and the control groups in terms of age, gender, related medical history, MGD stage, and all examined indexes, with the exception of conjunctival staining. OSDI, TBUT, meibum quality, MG expressibility, and MG dropout improved after treatment in both of the two groups (all P < 0.05). The MG microstructure indexes, including the MG acinar longest diameter (ALD), MG acinar unit density (AUD), and the positive rate of inflammatory cells (ICs) around glandular structures were significantly improved in the IPL group. No improvements of microstructure were found in the control group.

Conclusion: IPL treatment improves the symptom score of patients, associated ocular-surface indexes, MG function, and MG macrostructure as well as eyelid hygiene. And IPL treatment particularly improves MG microstructure and decreases MG inflammation in MGD patients.

2.

Vora GK, Gupta PK. Intense pulsed light therapy for the treatment of evaporative dry eye disease. Curr Opin Ophthalmol. 2015;26(4):314–18