Efficacy of Low-Level Light Therapy in Reducing Dry Eye in Patients Undergoing Cataract Surgery

Study Overview
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Brief Summary
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The goal of this clinical trial is to evaluate the effectiveness of Low Level Light Therapy (LLLT) in reducing the incidence or alleviating the severity of DED due to meibomian gland dysfunction in otherwise healthy patients undergoing cataract surgery. Participants will be randomly assigned in a 1:1 ratio to either a treatment group or a control group. The treatment group will receive LLLT one week before and one week after cataract surgery; the control group will not recieve LLLT at any time. Researchers will compare the treatment and the control group to see if patients receiving LLLT present with reduced signs and symptoms of ocular surface dysfunction with respect to the control group.

Official Title
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Effect of Low-Level Light Therapy Prior to Cataract Surgery: A Prospective, Randomized Controlled Study

Conditions
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Dry Eye

Intervention / Treatment
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* Device: Low Level Light Therapy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: healthy patients affected by senile cataract patients scheduled for phacoemulsification and intraocular lens implantation Exclusion Criteria: any other ocular comorbidity (e.g. glaucoma), chronic instillation of eye drops of any type previous ocular surgery or trauma to the addressed eye previous cataract surgery in the controlateral eye, active ocular infections use of systemic drug with a known or suspected link to dry eye (e.g. diuretics, antidepressants, antihistamines, hormone replacement therapy) autoimmune diseases (e.g. Sjögren syndrome) intraoperative complications (e.g. capsular bag rupture requiring vitrectomy, suprachoroidal hemorrhage) postoperative complications (e.g. endophthalmitis, vitritis)

Ages Eligible for Study
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Minimum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low Level Light Therapy Group<br>Patients enrolled in the treatment group will undergo Low Level Light therapy using Meibomask (Espansione Marketing S.p.A., Bologna, Italy) for 15 minutes one week (±2 days) before surgery (T0) and one week (±2 days) after surgery (T1). | Device: Low Level Light Therapy<br>* light-emitting diodes (LED), λ = 633 ± 10 nm; power of 100 mW/cm2, 15 minutes<br>|
| No Intervention: Control group<br>Patients enrolled in the control group will not receive Low Level Light therapy at any time. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Development or worsening of ocular surface abnormalities: tear meniscus height | Evaluation based on Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). Measurement expressed in millimeters. | One week (±2 days) after cataract surgery | 
| Development or worsening of ocular surface abnormalities: non-invasive keratograph break up time (NIKBUT) FIRST | Evaluation based on slit lamp examination and Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). NIKBUT FIRST: interval time between the last complete blinking and the first distortion the 22 concentric rings reflected on the corneal surface. Measurement expressed in seconds. | One week (±2 days) after cataract surgery | 
| Development or worsening of ocular surface abnormalities: non-invasive keratograph break up time (NIKBUT) AVG | Evaluation based on slit lamp examination and Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). NIKBUT AVG: average time of all tear film break-ups occurring in the measured period of up to 24.98 seconds (time limit set by the device's software). Measurement expressed in seconds. | One week (±2 days) after cataract surgery | 
| Development or worsening of ocular surface abnormalities: non-invasive keratograph break up time (NIKBUT) CLASS | Evaluation based on slit lamp examination and Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). NIKBUT CLASS: classification incorporated in the instrument: class 0 > 10 s (normal), class I 6 - 10 s, class II 3 - 6 s, class III < 3 s.Measurement expressed in seconds. | One week (±2 days) after cataract surgery | 
| Development or worsening of ocular surface abnormalities: bulbar redness | Evaluation based on Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). This parameter is expressed as as a ratio of vessels/free sclera and is automatically calculated by the instrument. | One week (±2 days) after cataract surgery | 
| Development or worsening of ocular surface abnormalities: meibomian gland dropout | Evaluation based on Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). Dropout is calculated according to the JENVIS meibo scale. Grade 0= no dropout; grade 1= area of gland loss up to 33% of the total gland area; grade 2 = area of gland loss between 33 and 66%; grade 3 = area of gland loss of 67% or more | One week (±2 days) after cataract surgery | 
| Development or worsening of ocular discomfort symptoms. | Evaluation based on the ocular surface disease index (OSDI) questionnaire. Normal OSDI: 0-12; a score of 13 or more is suggestive of dry eye disease (DED) Mild DED = 13 - 22; Moderate DED = 23-32; Severe DED > 32 | One week (±2 days) after cataract surgery | 
| Development or worsening of ocular surface abnormalities: tear meniscus height | Evaluation based on Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). Measurement expressed in millimeters. | One month (±7 days) after cataract surgery | 
| Development or worsening of ocular surface abnormalities: non-invasive keratograph break up time (NIKBUT) FIRST | Evaluation based on slit lamp examination and Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). NIKBUT FIRST: interval time between the last complete blinking and the first distortion the 22 concentric rings reflected on the corneal surface. Measurement expressed in seconds. | One month (±7 days) after cataract surgery | 
| Development or worsening of ocular surface abnormalities: non-invasive keratograph break up time (NIKBUT) AVG | Evaluation based on slit lamp examination and Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). NIKBUT AVG: average time of all tear film break-ups occurring in the measured period of up to 24.98 seconds (time limit set by the device's software). Measurement expressed in seconds. | One month (±7 days) after cataract surgery | 
| Development or worsening of ocular surface abnormalities: non-invasive keratograph break up time (NIKBUT) CLASS | Evaluation based on slit lamp examination and Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). NIKBUT CLASS: classification incorporated in the instrument: class 0 > 10 s (normal), class I 6 - 10 s, class II 3 - 6 s, class III < 3 s.Measurement expressed in seconds. | One month (±7 days) after cataract surgery | 
| Development or worsening of ocular surface abnormalities: bulbar redness | Evaluation based on Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). This parameter is expressed as as a ratio of vessels/free sclera and is automatically calculated by the instrument. | One month (±7 days) after cataract surgery | 
| Development or worsening of ocular surface abnormalities: meibomian gland dropout | Evaluation based on Oculus Keratograph 5 M (K5 M; Oculus GmbH, Wetzlar, Germany). Dropout is calculated according to the JENVIS meibo scale. Grade 0= no dropout; grade 1= area of gland loss up to 33% of the total gland area; grade 2 = area of gland loss between 33 and 66%; grade 3 = area of gland loss of 67% or more. | One month (±7 days) after cataract surgery | 
| Development or worsening of ocular discomfort symptoms. | Evaluation based on the ocular surface disease index (OSDI) questionnaire. Normal OSDI: 0-12; a score of 13 or more is suggestive of dry eye disease (DED) Mild DED = 13 - 22; Moderate DED = 23-32; Severe DED > 32 | One month (±7 days) after cataract surgery |