Discussion
Dryness, telangiectasia, hair loss, acne, floaters
POST-INFLAMMATORY HYPERPIGMENTATION, EYE, ADVERSE EFFECTS, CONJUNCTIVAL CYSTS, HAIR LOSS, ACNE, ATROPHIC
The current study showed that even without anti-inflammatory eye drops or eyelid management, IPL treatment significantly improved clinical symptoms and signs of MGD, including the OSDI score, TBUT, ocular staining scores, and MG parameters. Although the acne filter showed better treatment efficacy than the 590-nm filter, there were no significant differences in the TBUT, Oxford scale, SICCA staining score, MMP-9 expression, tear osmolarity, and MG parameters between both filters. Additionally, regardless of filter type, the responding subgroup showed worse baseline lower lid meibum expressibility and lower lid meibum secretion scores than those in the non-responding subgroup. Interestingly, in the acne filter group, the responding subgroup showed worse baseline TBUT and upper lid meibum expressibility than those in the non-responding subgroup.Several meta-analyses reported that the TBUT and Standard Patient Evaluation of Eye Dryness (SPEED) scores improved after IPL treatment in patients with MGD. However, the SPEED score improvement was not significantThe mechanism underlying IPL treatment remains unclear. In general, the IPL is considered to liquify meibum through heating. Other suggested mechanisms for IPL include photo-modulation, eradication of Few studies have compared IPL filters for MGD treatment, and no studies have considered direct comparisons between the filters. To our knowledge, this study is the first to directly compare two filters in a prospective, randomized, paired-eye study. IPL treatment with both 590-nm and acne filters showed good therapeutic efficacy for MGD; however, no significant differences were observed in the clinical parameters between the 590-nm and acne filters. As previously mentioned, IPL with an acne filter emits 400–600 nm and 800–1200 nm of wavelength energy, unlike a conventional cut-off filter (590-nm filter). The light between the two bands (600–800 nm) is highly absorbed by melanin and is associated with a risk of epidermal damage and post-inflammatory hyperpigmentation. A dual-band filter enables more selective targeting. For example, in dermatology, the acne filter is applied to acne treatment. The 400–600-nm wavelength energy can target porphyrin and destroy Although we expected improved efficacy in lid margin telangiectasia via deeper penetration and better vascular-to-pigment destruction ratio with the acne filter, no significant difference was found in lid margin telangiectasia between the two filters. To date, no effective method of evaluating superficial and deep lid margin telangiectasia has been developed. Recent studies, including our study, have depended on a slit lamp examination to evaluate and grade lid telangiectasia, which is limited to examination of the superficial layer. Therefore, to evaluate the effect of IPL with a notch filter (acne or vascular filter) on telangiectasia at a deeper layer, more advanced technology is necessary.Previous studies on the prognostic factors of IPL have reported that patients with MGD with longer baseline TBUT and less atrophic change in MG showed better therapeutic efficacyThis study has some limitations. First, the number of enrolled patients was relatively small. Second, the follow-up period was relatively short-term. Nevertheless, our study may be the first prospective, randomized design to compare the efficacy of IPL treatments between cut-off and notch filters through paired-eye design. Our results also showed a significant therapeutic effect of IPL on MGD under strictly controlled self-administration of other treatment modalities. According to one study, 14% of patients had adverse effects after IPL, including conjunctival cysts, floaters, hair loss, blistering, light sensitivity, and rednessIn summary, IPL alone is a clinically efficacious treatment for moderate to severe MGD. Regarding the filter selection, both acne and 590-nm filters are promising options for MGD treatment.