Comparison of SRK-T With Kane Formula for Prediction of Refractive Outcome After Phacoemulsification

Study Overview
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Brief Summary
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Cataract is a leading cause of blindness in the world. Cataract surgery is one of the most commonly performed ocular procedures. We aim to compare the newer generation biometry formula; the Kane formula with the commonly used SRK-T formula for intraocular power calculation in uneventful phacoemulsification surgery to assess the post-operative refractive outcomes at one month post-surgery.

Detailed Description
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Purpose: To compare post-operative refractive outcome with Sanders Retzlaff Kraff theoretical (SRK T) and Kane formulae for intraocular lens (IOL) power calculation in cataract patients Study Design: Prospective, interventional study Place and Duration of Study: Department of Ophthalmology, Fauji Foundation Hospital, Rawalpindi Material and Methods: A total of a 70 eyes, 35 in each group will be included in our study. The patients will be randomly divided into two groups. In cases of bilateral cataract, one eye will be included in each group for better control. IOL power calculation in Group A will be done with the SRK-T formula and in group 2 with the Kane Formula. Autokeratometry and A-scan ultrasound will be done for biometry. Inclusion criteria will be uncomplicated cataract in both genders. Exclusion criteria will be ocular trauma, uveitis, previous intraocular surgery, or any retinopathy. All patients will undergo phacoemulsification with foldable lens implantation by two experienced surgeons. Post-operative refractive outcome will be evaluated at one month after surgery. The two groups will be compared. Results: The results will be calculated by SPSS. Conclusion: A conclusion will be drawn on the basis of our results.

Official Title
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Comparison of SRK-T With Kane Formula for Prediction of Refractive Outcome After Phacoemulsification

Conditions
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Cataract; Surgery; Phacoemulsification; Biometry; Intraocular Lens Power

Intervention / Treatment
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* Other: Biometry with Kane formula
* Other: Biometry with SRK-T formula


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Senile cataract (nuclear, cortical, posterior subcapsular, mature, hypermature cataract) Absence of other ocular pathology causing diminished visual acuity patients above 40 years of age Astigmatism > 2.5 diopters Exclusion Criteria: Retinal diseases Maculopathy Uveitis Complications during phacoemulsification Combined procedures Previous ocular surgery Trauma Secondary cataract

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 100 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Prospective, interventional study
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: SRK-T Formula for Prediction of refraction<br>To compare post-operative refractive outcome with Sanders Retzlaff Kraff theoretical (SRK T) and Kane formulae for intraocular lens (IOL) power calculation in cataract patients | Other: Biometry with SRK-T formula<br>* Sanders Retzlaff Kraff theoretical (SRK T) formulae for intraocular lens (IOL) power calculation in cataract patients<br>|
| Active Comparator: Kane Formula for Prediction of refraction<br>To compare post-operative refractive outcome with Sanders Retzlaff Kraff theoretical (SRK T) and Kane formulae for intraocular lens (IOL) power calculation in cataract patients | Other: Biometry with Kane formula<br>* Kane formulae for intraocular lens (IOL) power calculation in cataract patients<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual acuity (Snellen/logMAR) and refractive error (automated refraction in diopters) | The visual acuity and refractive error of the patients will be measured 1 month post-operatively to compare between the two groups | 1 month post-operatively | 
| Spherical equivalent in diopters | The spherical equivalent of the patients will be measured 1 month post-operatively to compare between the two groups | 1 hour to 1 year | 
| Post-operative refractive outcome in diopters | Post-operative refractive outcome will be compared with intended refractive outcome | 1 hour to 1 year |