Axial Length Variability

Study Overview
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Brief Summary
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The accuracy of IOL calculation relies on the one hand on axial length measurements and on the other hand on corneal and lens thickness measurements. AL difference in pre and postoperative measurements may be caused by changes of lens parameters. Aim of this study is to evaluate the magnitude of changes in pre and postoperative measurements of AL.

Detailed Description
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This is a prospective observational, controlled and unmasked study that would include patients which undergo cataract presurgical examination, after patient signed written informed consent. For each patient only one eye will be included. In total 50 eyes of 50 patients will be include. Due to missing previous data, the sample size is an approximation. Prior to surgery, slit lamp examination and cataract grading (LOCS) is performed. Routine biometry is performed using the IOL Master 700 (Carl Zeiss Meditec AG, Jena, Germany) and Heidelberg Anterion (Heidelberg Engineering, Germany) for AL and lens measurement. Additionally, evaluation of tilt and decentration will be performed using Purkinje meter device. Follow-up examination will be performed three months after surgery and will contain: AL and lens measurement using the two ss-OCT biometery devices, lens evaluation (tilt and decentration of the IOL) using the Purkinje meter. Refractive outcome will be evaluated by determining best-corrected visual acuity and subjective refraction. In women of childbearing age, a pregnancy test will be performed before inclusion into the study. Main outcome variable: • Extend of AL difference between pre- and postoperative measurements in both devices Additional outcome variables: Agreement between the two ss-OCT devices in AL measurement Evaluation of lens parameter in AL differences between pre- and postoperative measurements Limit of agreement in lens tilt and decentration using two ss-OCT devices and Purkinje meter

Official Title
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Evaluation of Axial Length Changes Between Pre and Postoperative Measurements

Conditions
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Cataract Senile

Intervention / Treatment
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* Other: Axial length variability


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Uneventful cataract surgery Age 21 and older Axial length 24.00 mm and bigger CT Asphina 409 M lens implanted Exclusion Criteria: Intra- or postoperative complication Relevant other ophthalmic diseases that are likely to influence the measurement outcome (as: with severe corneal pathology, severe macular degeneration, severe diabetic retinopathy, dens cataract, PEX syndrome, previous ocular surgery or trauma) Pregnancy

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 100 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: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Axial length variability<br>Aim of this study is to evaluate the magnitude of changes in pre and postoperative measurements of AL. | Other: Axial length variability<br>* Biometry (axial length measurement)is performed using the IOL Master 700 (Carl Zeiss Meditec AG, Jena, Germany) and Heidelberg Anterion (Heidelberg Engineering, Germany) pre and postoperatively.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Axial length variability | Evaluation of changes in axial length pre and post cataract surgery using two ss-OCT biometers | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Lens tilt and decentration | Evaluation of lens tilt and decantation using the Purkinje meter and two ss-OCT devices | 3 months |