Pseudophakic Anterior Chamber Depth Measurement in Second Eye Refinement Cataract Surgery

Study Overview
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Brief Summary
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To study the effective lens position concept in second eye refinement (SER) cataract surgery, by relating inter-ocular symmetry of pseudophakic anterior chamber depth (pACD) measured in Pentacam and SER refractive outcomes.

Detailed Description
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A retrospective chart review was conducted, including demographics (age and gender) and several parameters for both the first and second eyes, including the intra-ocular lens power calculation using the HofferQ, SRK/T and Holladay 1 formulas. Pentacam HR was used for pseudophakic anterior chamber depth measurement, and manual measurement was performed by a single investigator tracing a line between the anterior surface of the intra-ocular lens and the central corneal epithelium apex. Second eye refinement in the intra-ocular lens power selection for the second eye was performed using a theoretical 50% partial adjustment of the prediction error of the first eye. To relate refractive outcomes to pACD values, the investigators performed subgroup analysis based in consecutive 50µm increments in inter-ocular asymmetry of pACD (50-600).

Official Title
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Pseudophakic Anterior Chamber Depth Measurement in Second Eye Refinement Cataract Surgery

Conditions
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Cataract

Intervention / Treatment
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* Procedure: 50% Partial adjustment
* Procedure: No adjustment
* Procedure: Full adjustment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients admitted for bilateral age-related cataract surgery Exclusion Criteria: Age < 18 years old Previous or combined ocular surgery Manual extracapsular cataract extraction and not phacoemulsification Corneal sutures Implantation of any other IOL type IOL implanted in the sulcus Intra or postoperative complication Post-operative best-corrected visual acuity worse than 5/10 Anterior corneal astigmatism>3.00 D Inadequate cooperation for Pentacam HR examination

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 50% Partial adjustment<br>The prediction error for the first (PE1) and second (PE2) eyes was calculated as the difference between the observed post-operative refraction in spherical equivalent and the predicted post-operative refraction by the IOL Master for the implanted intra-ocular lens. This was obtained for the 3 formulae. Second eye refinement in the intra-ocular lens power selection for the second eye was performed using a theoretical 50% partial adjustment of the PE1. To relate refractive outcomes to pACD values, we performed subgroup analysis based in consecutive 50µm increments in inter-ocular asymmetry of pACD (50-600). | Procedure: 50% Partial adjustment<br>* Second eye refinement in the IOL power selection for the second eye using a theoretical 50% partial adjustment of the PE1.<br>|
| No adjustment<br>The prediction error for the first (PE1) and second (PE2) eyes was calculated as the difference between the observed post-operative refraction in spherical equivalent and the predicted post-operative refraction by the IOL Master for the implanted intra-ocular lens. This was obtained for the 3 formulae. The intra-ocular lens power selection for the second eye was performed irrespective of the first eye prediction error. To relate refractive outcomes to pACD values, we performed subgroup analysis based in consecutive 50µm increments in inter-ocular asymmetry of pACD (50-600). | Procedure: No adjustment<br>* IOL power selection for the second eye irrespective of first eye prediction error<br>|
| Full adjustment<br>The prediction error for the first (PE1) and second (PE2) eyes was calculated as the difference between the observed post-operative refraction in spherical equivalent and the predicted post-operative refraction by the IOL Master for the implanted intra-ocular lens. This was obtained for the 3 formulae. Second eye refinement in the intra-ocular lens power selection for the second eye was performed using a theoretical 100% partial adjustment of the PE1. To relate refractive outcomes to pACD values, we performed subgroup analysis based in consecutive 50µm increments in inter-ocular asymmetry of pACD (50-600). | Procedure: Full adjustment<br>* Second eye refinement in the IOL power selection for the second eye using a theoretical 100% partial adjustment of the PE1.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Second eye mean absolute error | Mean of the absolute value of the prediction error of the second eye | 4-6 weeks after second eye surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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cataract surgery, biometry, second eye refinement, effective lens position