Effect of Artificial Tears on the Parameters of the Eye and Its Impact on IOL Power Calculation for Cataract Surgery
Study Details
Study Description
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)
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
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)
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Active Comparator: 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. |
Device: sodium hyaluronate 0.1%
Instillation of one drop sodium hyaluronate 0.1%
|
| Active Comparator: 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. |
Device: sodium hyaluronate 0.3%
Instillation of one drop sodium hyaluronate 0.3%
|
Outcome Measures
Primary Outcome Measures
- 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)
- 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)
- 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 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),
- 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)
Eligibility Criteria
Criteria
Inclusion Criteria:
-
A patient diagnosed with age related cataract
-
30 to 95 years old
-
Medical history and physical examination should be normal.
Exclusion Criteria:
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• Abnormality of the cornea (scaring of the cornea)
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If any topical therapy (i.e. glaucoma) of the eye is needed
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Active allergy of eye or nose
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Any conjunctivitis or keratitis
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If nasolacrimal drainage apparatus is abnormal
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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
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Preceding eye trauma or surgery
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Any Uncontrolled ocular disease or systemic disease
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Lactation
-
Pregnancy
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Department of Ophthalmology, Second affiliated hospital of Xian Jiaotong University | Xi'an | Shaanxi | China | 710004 |
Sponsors and Collaborators
- Second Affiliated Hospital of Xi'an Jiaotong University
Investigators
- Principal Investigator: Ling Bai, MD,PhD, Second Affiliated Hospital of Xi'an Jiaotong University
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- 20210312