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Effect of Artificial Tears on the Parameters of the Eye and Its Impact on IOL Power Calculation for Cataract Surgery

Not Applicable
Conditions
Dry Eye
Cataract Senile
Interventions
Device: sodium hyaluronate 0.3%
Device: sodium hyaluronate 0.1%
Registration Number
NCT04706455
Lead Sponsor
Second Affiliated Hospital of Xi'an Jiaotong University
Brief Summary

First, preoperative biometry of the eye at the IOL Master® will be performed. Then, corneal topography will be measured at the Oculus pentacam®. Afterwards, one of two eye drops are instilled in the eye, and biometry and corneal topography will be repeated after 5 minutes.

For all patients, the Barrett Universal II formula will be used for calculation of IOL power. Predicted refraction outcome will be referred to as SEQ. The chief surgeon will perform the uneventful standard cataract operation with in-the-bag implantation of a HOYA IOL (Model 251) through a 2.4-mm corneal incision.

A Subjective Refraction using plus principle will be performed one month after the operation, and ETDRS visual acuity charts will be used to measure best-corrected visual acuity. Refraction will be described as SR (postoperative SEQ) and will be calculated as:

SR = sphere + (0.5\*cylinder)

Detailed Description

First, preoperative biometry of the eye at the IOL Master® will be performed. Then, corneal topography will be measured at the Oculus pentacam®. Patients will be classified as dry eye or normal eye based on BUT. The tear film breakup (BUT) time of less than 5 seconds will be diagnosed as dry eyes.Afterwards, one of two eye drops are instilled in the eye, and biometry and corneal topography will be repeated after 5 minutes.

For all patients, the Barrett Universal II formula will be used for calculation of IOL power. Predicted refraction outcome will be referred to as SEQ. The chief surgeon will perform the uneventful standard cataract operation with in-the-bag implantation of a HOYA IOL (Model 251) through a 2.4-mm corneal incision.

A Subjective Refraction using plus principle will be performed one month after the operation, and ETDRS visual acuity charts will be used to measure best-corrected visual acuity. Refraction will be described as SR (postoperative SEQ) and will be calculated as:

SR = sphere + (0.5\*cylinder)

Recruitment & Eligibility

Status
UNKNOWN
Sex
All
Target Recruitment
60
Inclusion Criteria
  • A patient diagnosed with age related cataract
  • 30 to 95 years old
  • Medical history and physical examination should be normal.
Exclusion Criteria
  • • Abnormality of the cornea (scaring of the cornea)

    • If any topical therapy (i.e. glaucoma) of the eye is needed
    • Active allergy of eye or nose
    • Any conjunctivitis or keratitis
    • If nasolacrimal drainage apparatus is abnormal
    • severity level 4 of dry eye (constant discomfort in the eye accompanied with visual symptoms, filamentary keratitis, , keratinization, severe conjunctival injection, ulceration clumping of mucus glands, tear debris, , trichiasis, symblepharon)
    • deformities of lid
    • Preceding eye trauma or surgery
    • Any Uncontrolled ocular disease or systemic disease
    • Lactation
    • Pregnancy

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
sodium hyaluronate 0.3%sodium hyaluronate 0.3%First preoperative Biometry of the eye at the IOL Master® will be measured. Then,corneal topography will be measure at the Oculus pentacam®. Afterwards, sodium hyaluronate 0.3% will be installed and biometry and corneal topography will be repeated after 5 minutes.
sodium hyaluronate 0.1%sodium hyaluronate 0.1%First preoperative Biometry of the eye at the IOL Master® will be measured. Then, corneal topography will be measure at the Oculus pentacam®. Afterwards, sodium hyaluronate 0.1% will be installed and biometry and corneal topography will be repeated after 5 minutes.
Primary Outcome Measures
NameTimeMethod
keratometric value of the eye measured with Master 500 before and after 5 minutes of installation of artificial tears (sodium hyaluronate 0.1% or 0.3% eye drops).5 minutes

k-value (k, k1, k2 in Diopter)

Sim K of the eye measured with Oculus Pentacam before and after 5 minutes of installation of artificial tears (sodium hyaluronate 0.1% or 0.3% eye drops).5 minutes

Sim K (k1, k2 in Diopter)

Total Corneal Irregular Astigmatism of the eye measured with Oculus Pentacam before and after 5 minutes of installation of artificial tears (sodium hyaluronate 0.1% or 0.3% eye drops).5 minutes

Total Corneal Irregular Astigmatism (TCIA in Diopter)

Predicted spherical equivalent (SE) calculated with Barrett Universal II formula before and after 5 minutes of installation of artificial tears (sodium hyaluronate 0.1% or 0.3% eye drops).5 minutes

Predicted spherical equivalent (SEQ in Diopter)

Postoperative spherical equivalent (SE) measured one month after surgery.one month after surgery

Postoperative spherical equivalent (SE in Diopters)

Axial length of the eye measured with Master 500 before and after 5 minutes of installation of artificial tears (sodium hyaluronate 0.1% or 0.3% eye drops).5 minutes

Axial length (AL in mm)

Anterior chamber depth of the eye measured with Master 500 before and after 5 minutes of installation of artificial tears (sodium hyaluronate 0.1% or 0.3% eye drops).5 minutes

Anterior chamber depth (ACD in mm)

Total Corneal Refractive Power of the eye measured with Oculus Pentacam before and after 5 minutes of installation of artificial tears (sodium hyaluronate 0.1% or 0.3% eye drops).5 minutes

Total Corneal Refractive Power (TCRP in Diopter),

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (1)

Department of Ophthalmology, Second affiliated hospital of Xian Jiaotong University

🇨🇳

Xi'an, Shaanxi, China

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