Therapeutic effect of intense pulsed light on different types of chalazion in children

This study aims to investigate the effectiveness of Intense Pulsed Light (IPL) therapy for chalazion treatment while also exploring potential variations in sensitivity among different types of chalazion. A total of 149 patients were selected to receive tobramycin combined with IPL treatment and tobramycin combined with hot compress. The treatment groups were divided into cystic type and granulomatous type according to different clinical manifestations. The course of treatment was 3 weeks. The improvement was based on the ultrasound measurement of the masses reduction of more than 50% or disappearance. In the IPL group, 17 (22.67%) cases were cured, 39 (52.00%) were effective, and 19 (25.33%) were ineffective. This includes: cystic type was cured in 3 (15.79%), effective in 5 (26.32%) cases, ineffective in 11 (57.89%) cases; granulomatous type was cured in 14 (25.00%) cases, effective in 34 (60.71%) cases, ineffective in 8 (14.29%) cases. In the hot compress group, 5 (6.76%) cases were cured, 16 (21.62%) cases were effective and 53 (71.62%) cases were ineffective. The cystic type was cured in 2 (8.00%) cases, effective in 3 (12.00%) cases and ineffective in 20 (80.00%) cases; the granulomatous type was cured in 3 (6.12%) cases, effective in 13 (26.53%) cases and ineffective in 33 (67.35%) cases. The cure rate and efficacy rate of IPL treatment is higher than that of hot compress treatment, the treatment effect of IPL treatment on granulomatous chalazion is better than that on cystic type.


Treatment methods
(1) Hot compress treatment group: tobramycin eye drops were applied to the affected eye (one drop at a time, three times daily) combined with local hot compress on the affected eyelid.The hot compress was performed using sterile gauze or towel soaked in warm water (temperature slightly higher than body surface temperature, ranging from 38 to 42 ℃), applied locally to the affected eye.This procedure was conducted twice daily for 5 to 10 min each time.(2) IPL treatment group: tobramycin eye drops combined with IPL treatment, using the "EYESIS light pulse MOPT treatment instrument for meibomian gland dysfunction (MDC)" for IPL treatment.The children were placed in the supine position, a ceramic eye mask was used to cover both eyes, and coupling agent was applied to the lower eyelid and temporal side.After wearing the protective mirror, the clinician held the treatment handle and performed the IPL treatment from the nasal side of the lower eyelid to the temporal side, administering five irradiations per eye.The pulsed light energy ranged between 8 and 12 J/cm 2 , initially starting at a lower energy level, which was adjusted based on individual tolerance.Treatment sessions were conducted once a week for a total of three repetitions.
The children were followed up after the treatment to see if there was any adverse reaction.

Evaluation of efficacy
The duration of the treatment regimen for both groups was 3 weeks.The maximum diameter of chalazia were measured and recorded by color Doppler ultrasound before and after treatment.
(1) Cure: the chalazion resolved completely, without any palpable nodules on either eyelid, and no signs of conjunctival congestion were observed on the palpebral surface.(2) Effective: the cyst or granuloma was significantly reduced after treatment, and the length of the cyst was reduced by 50% or more as confirmed by color Doppler ultrasound.(3) Ineffective: there were no significant changes in the size and shape of the mass before and after treatment, and the length of the mass changed within 50% as measured by color Doppler ultrasound, or chalazion worsening including mass enlargement, increase in number, disease progression.

Statistical analysis
Statistical software SPSS26.0 was used for analysis.Statistical data were expressed as n (%).Chi-square test or Fisher's exact test was used to compare data between different groups.Quantitative data were expressed as mean and standard deviation, and analysis of variance (ANOVA) and least significant difference (LSD) was used to compare components.P < 0.05 indicated a statistically significant difference.

Results
Gender, age and disease duration of patients with different types of chalazia who received IPL and hot compress treatment  1).

Comparison of the therapeutic effect between the IPL treatment group and the hot compress treatment group
There were 75 cases in the IPL group, of which 17 (22.67%)were cured (the mean diameter measured 4.31 ± 1.73 mm prior to treatment and 0 ± 0 mm post-treatment), 39 (52.00%) were effective (The mean diameter measured 4.72 ± 2.16 mm prior to treatment and 1.84 ± 0.83 mm post-treatment), and 19 (25.33%) were ineffective (the mean diameter measured 3.92 ± 1.68 mm prior to treatment and 4.22 ± 1.67 mm post-treatment).There were 74 cases in the hot compress treatment group, of which 5 (6.76%) were cured (the mean diameter measured 4.63 ± 2.05 mm prior to treatment and 0 ± 0 mm post-treatment), 16 (21.62%)were effective (the mean diameter measured 4.42 ± 2.16 mm prior to treatment and 2.16 ± 0.95 mm post-treatment), and 53 (71.62%) were ineffective (the mean diameter measured 4.18 ± 1.86 mm prior to treatment and 4.41 ± 2.17 mm post-treatment) (Fig. 1).
After treatment, the cure rate and efficacy rate of the IPL group were higher than that of the hot compress group, the difference was statistically significant (P < 0.05) (Table 2).No adverse reactions were found in any of the treatment groups.www.nature.com/scientificreports/(8.00%) cases of cystic type cured, 3 (12.00%)effective, 20 (80.00%) ineffective; 3 (6.12%)cases of granulomatous type cured, 13 (26.53%)effective,33 (67.35%) ineffective (Fig. 2).( 2) The treatment effect of IPL on granulomatous chalazion was better than that on cystic chalazion, and the cure rate and effective rate of the granulomatous type were higher than those of the cystic type, the difference was statistically significant (P < 0.05) (Table 3).(3) There was no significant difference in the therapeutic effect of hot compress treatment on cystic and granulomatous chalazion (P > 0.05) (Table 4).( 4) There was no significant difference between IPL treatment and hot compress.treatment for cystic chalazion (P > 0.05) (Table 5).( 5) For granulomatous chalazion, the therapeutic effect of IPL was better than that of hot compress.The cure rate and efficacy rate of IPL were higher than that of hot compress, and the difference was statistically significant (P < 0.05) (Table 6).

Discussion
Chalazion is a chronic aseptic inflammatory granuloma that forms after obstruction of the meibomian gland ducts and accumulation of secretions in the gland 11 .Treatment options include conservative management, local glucocorticoid injection and surgical incision 1 .Many researchers have carried out in-depth studies of different treatments for chalazion [2][3][4][5][6] .Wu AY et al. 2 found that tobramycin eye drops combined with hot compress reduced cysts by more than 50% in 45% of patients.In our study, utilizing tobramycin combined with hot compress resulted in an improvement rate (effective rate + cure rate) of 28.38%.The reason for this difference may be the poor compatibility of eye drop application and hot compress treatment for children in this study.Gowalla et al. 3 showed that the cure rate of chalazion after triamcinolone injection and surgery was 84% and 87% respectively.In Nabie R's study, the success rates of intravitreal triamcinolone and surgery were 61.5% and 84% respectively.In our study, IPL treatment achieved an improvement rate reaching as high as 74.67%, significantly surpassing Wu AY's conservative approach while closely resembling the efficacy observed with invasive hormone therapy and surgery.The results showed that IPL treatment has a significant effect on the chalazion (Fig. 3).Chalazion usually grow slowly and painlessly 11 , which is difficult to detect in its early stages.Especially for children, most patients are treated in hospital for local swelling caused by concomitant infection.The exact time of onset is difficult to trace, and the course of cysts can only be assessed by clinical physical examination.In this study, chalazion was divided into cystic type and granulomatous type according to different morphological characteristics.The treatment effect of IPL for granulomatous chalazion was superior to that for the cystic type, with an improvement rate as high as 85.71%, which was similar to the success rate of surgical treatment.There is no difference between hot compress treatment of cyst type and granulomatous type.At the same time, there was no significant difference in the therapeutic effect between IPL and hot compress for cystic chalazion, while for granulomatous chalazion, the therapeutic effect of IPL was significantly superior to hot compress.In general, IPL has a significant effect on the granulomatous chalazion.The reason for this result may be related to the mechanism of IPL therapy.
IPL energy is delivered in the form of pulses, light is absorbed by different target organs and converted into heat, and selective photothermal action avoids non-specific thermal damage in the treatment area 12 .IPL can destroy the abnormal blood capillaries of the chalazion and reduce the release of inflammatory mediators, thereby reducing the chronic inflammatory response 13,14 .The temperature of palpebral sebum can reach 35-38 ℃, and palpebral sebum can be successfully discharged from meibomian gland after liquefaction, However, the heating effect on the glands is temporary and it is difficult to achieve continuous blepharon drainage.Many studies have shown that Demodex infection may be one of the risk factors for chalazion in children 15,16 , and IPL can kill demodex through instantaneous high temperature 17 .
Different treatment methods have their own advantages and disadvantages.Although the effectiveness of antibiotic eye drops combined with hot compress treatment for chalazion is limited, it offers the benefits of minimal trauma, fewer adverse reactions, and convenient operation, making it a preferred initial choice for diagnosis.Local glucocorticoid injection and surgery are used in patients who do not show significant resolution of masses after a period of conservative treatment 2,11 .A study by Dhaliwal and Bhatia 18 showed that incision and curettage of chalazion is an effective treatment option for all chalazia, particularly complex cases near the lacrimal ductule or eyelid margin.However, surgical resection, especially of recurrent and multiple chalazia, can result in palpebral conjunctival and skin scarring 19 , and resection of larger masses can easily result in the absence of meibomian glands, leading to chronic meibomian gland dysfunction (MGD) 20 .No adverse reactions were observed during IPL treatment in this study or previous studies on ocular surface disease using IPL [7][8][9][10] .There are still some shortcomings in our study.Firstly, the sample size of this study is small, which may lead to bias caused by various factors.Therefore, the results of this study need to be further verified by large-scale, randomized controlled and multicentre prospective studies.Secondly, in our study, chalazia were observed according to different forms of clinical physical examination, which is highly subjective and leads to greater risk of misjudgment.Hence, more appropriate differential diagnosis approaches should be explored in future research endeavors.Additionally, color Doppler ultrasound was utilized with high precision to assess treatment efficacy in our study.Subsequently, by integrating information such as echo and blood flow within the lesion using ultrasound imaging techniques, it becomes feasible to determine specific subtypes of chalazion.

Conclusions
In conclusion, the results of our study suggest that IPL treatment is effective for children with chalazia, especially the granulomatous type.For newly diagnosed children with chalazia, antibiotic eye drops combined with IPL can be chosen as treatment.After treatment, surgical treatment may be chosen depending on the prognosis.

Table 1 .
Comparison of age, gender and duration differences between the four groups.

Table 2 .
Comparison of therapeutic effect between IPL group and HC group.

Table 3 .
Comparison of the therapeutic effects of IPL in the treatment of cystic and granulomatous chalazion.

Table 4 .
Comparison of the therapeutic effect of hot compress on cystic and granulomatous chalazion.

Table 5 .
Comparison of the therapeutic effect of IPL therapy and hot compress therapy on the cystic chalazion.

Table 6 .
Comparison of the therapeutic effect of IPL treatment and hot compress treatment on granulomatous chalazion.