Combined Intense Pulsed Light and Low-Level Light Therapy for the Treatment of Dry Eye: A Retrospective Before–After Study with One-Year Follow-Up

Figures & data

Table 1 Sociodemographic and Clinical Characteristics at Baseline

	n = 156
Age, (mean, sd, range)	54.0 (14.1) (30–77)
Female	124 (79.5%)
Fitzpatick skin type
I	3 (1.9%)
II	4 (2.6%)
III	48 (30.8%)
IV	92 (59.0%)
V	9 (5.8%)
Duration of DED in years (mean, sd, range)	5.9 (3.6) (1–12)
Conventional treatment during study:
- Artificial tears	156 (100%)
- Topical antibiotics	97 (62.2%)
- Topical steroids	52 (33.3)

Abbreviation: DED, dry eye disease.

Table 2 Results of Repeated-Measures ANOVA on the Dependent Variables (n = 156)

Outcome	6 Months Before Baseline^a	Baseline^a	Post (3 Months)^a	9 Months After Baseline^a	15 Months After Baseline^a	F (p-value)^b	6 Months Before vs Baseline^c	Baseline vs Post-Intervention^c	Baseline vs 15 Months^c
OSDI (0–100)	55.27 (23.42) (19–99)	58.29 (26.08) (15.40–100)	14.22 (6.28) (3.71–25.53)	21.14 (8.75) (5.36–37.36)	28.19 (12.54) (7.76–48.52)	213.97 (<0.001)	3.03 (1.000)	−44.08 (<0.001)	−30.10 (<0.001)
NIBUT (seconds)	4.30 (1.61) (1.64–7.11)	3.70 (1.77) (0.90–6.78)	8.85 (4.02) (2.21–15.56)	7.94 (3.49) (1.86–13.84)	7.34 (3.25) (1.80–12.68)	92.64 (<0.001)	−0.59 (0.018)	5.15 (<0.001)	3.63 (<0.001)
Osmolarity (mOsm/L)	319.17 (22.74) (281.0–358.0)	331.83 (21.61) (294.4–369.3)	278.96 (17.66) (246.0–308.9)	296.25 (19.73) (261.6.-328.1)	304.25 (18.02) (271.6–3.39.9)	160.15 (<0.001)	12.66 (<0.001)	−52.87 (<0.001)	−27.58 (<0.001)
Meniscal height (mm)	0.14 (0.04) (0.08–0.20)	0.12 (0.03) (0.07–0.18)	0.21 (0.05) (0.12–0.30)	0.16 (0.04) (0.09–0.23)	0.15 (0.03) (0.09–0.21)	119.45 (<0.001)	−0.02 (<0.001)	0.09 (<0.001)	0.03 (<0.001)

Notes: ^aMeans (sd) (range). ^bF (p-values) from repeated-measures ANOVA within-subject effects. ^cMean differences and p-values from paired t-tests, with Bonferroni adjustment for multiple comparisons.

Abbreviations: NIBUT, non-invasive break-up time; OSDI, Ocular Surface Disease Index.

Figure 1 Change in OSDI scores.

Figure 2 Change in NIBUT.

Figure 3 Change in osmolarity.

Figure 4 Change in meniscal height.

Table 3 Pearson’s Correlations Between the Dependent Variables (n = 156)

	Baseline			Post-Treatment (3 Month)			Last Follow Up (15 Months)
Outcome	NIBUT	Osmolarity	Meniscal Height	NIBUT	Osmolarity	Meniscal Height	NIBUT	Osmolarity	Meniscal Height
OSDI	−0.15	0.05	0.04	0.03	0.09	0.19*	−0.02	−0.04	0.09
NIBUT		0.06	−0.04		0.17*	0.06		−0.13	0.08
Osmolarity			0.09			0.13			−0.03

Note: *p<0.05.

Abbreviations: NIBUT, non-invasive break-up time; OSDI, Ocular Surface Disease Index.

Table 4 Multiple Linear Regression Models Predicting Change in the OSDI (n = 156)

	Change Baseline – Post Intervention^a		Change Baseline – 15 Months^a
Age	−0.03 (0.421)	−0.03 (0.403)	−0.19 (0.010)	−0.19 (0.010)
Female	1.51(0.231)	1.70 (0.171)	2.41 (0.334)	2.29 (0.361)
Duration of DED	0.08 (0.585)	0.02 (0.881)	0.15 (0.594)	0.19 (0.504)
Treated with antibiotics	−1.08 (0.306)	−0.98 (0.341)	1.92 (0.359)	1.67 (0.424)
Treated with steroids	0.63 (0.568)	0.65 (0.552)	1.49 (0.493)	1.56 (0.478)
Baseline OSDI	−0.97 (<0.001)	−0.97 (<0.001)	−1.02 (<0.001)	−1.01 (<0.001)
Baseline NIBUT	−0.14 (0.637)	–	−0.36 (0.538)
Change in NIBUT	–	0.03 (0.810)	–	−0.13 (0.639)
Baseline osmolarity	−0.01 (0.690)	–	−0.02 (0.700)
Change in osmolarity	–	0.02 (0.424)	–	0.01 (0.816)
Baseline meniscal height	−29.2 (0.076)	–	24.4 (0.453)
Change in meniscal height	–	21.1 (0.211)	–	7.64 (0.718)

Note: ^aUnstandardized coefficients (p-value).

Abbreviations: DED, dry eye disease; NIBUT, non-invasive break-up time; OSDI, Ocular Surface Disease Index.