Comparison of the Visual Quality of Traditional Ultrasound Biometrics and Lenstar on the Cataract After Pars Plana Vitrectomy

Study Overview
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Brief Summary
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Comparison of the visual quality of traditional ultrasound biometrics and lenstar on the cataract patients with diabetic retinopathy after vitrectomy in the 3 months later.To evaluate the clinical value of lenstar in post-vitrectomy patients.

Official Title
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Comparison of the Visual Quality of Traditional Ultrasound Biometrics and Lenstar on the Cataract After Pars Plana Vitrectomy

Conditions
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Diabetic Retinopathy Patients After Vitrectomy

Intervention / Treatment
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* Device: Traditional ultrasound biometrics
* Device: Lenstar


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with cataract after vitrectomy because of diabetic retinopathy. Patients with good fixation in order to cooperate with various examination. Exclusion Criteria: Myopia of >6 diopters Ocular trauma and other eye disease accepted vitrectomy,such as branch retinal vein occlusion(BRVO),central retinal vein occlusion(CRVO). Vision acuity <0.1 Silicone oil eye
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 |
| --- | --- |
| Group:Traditional ultrasonic biological<br>The measurement of axial length was performed in 60 eyes (30 eyes for each group) with senile cataract of vitrectomised eye of diabetic retinopathy using lenstar and traditional ultrasonic biological combined with cornea curvimeter.In this group,we use traditional ultrasonic biological combined with cornea curvimeter to measure the ocular parameter. | Device: Traditional ultrasound biometrics<br>* To evaluate the clinical feasibility of using a new optical coherence interferometry ( lenstar ),comparing with traditional ultrasonic biometry and keratometry in the accuracy and characteristics for intraocular lens calculation of cataract after PPV<br>|
| Group:Lenstar<br>The measurement of axial length was performed in 60 eyes (30 eyes for each group) with senile cataract of vitrectomised eye of diabetic retinopathy using lenstar and traditional ultrasonic biological combined with cornea curvimeter.In this group,we use lenstar to measure the ocular parameter. | Device: Lenstar<br>* To evaluate the clinical feasibility of using a new optical coherence interferometry ( lenstar ),comparing with traditional ultrasonic biometry and keratometry in the accuracy and characteristics for intraocular lens calculation of cataract after PPV<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the visual quality of the eye after surgery | the visual quality of the eye after surgery through optical path difference scan（OPD Scan） | one month | 
| the visual quality of the eye after surgery | the visual quality of the eye after surgery through optical path difference scan（OPD Scan） | three month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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cataract, higher order aberration,vitrectomy,diabetic retinopathy