Posterior Capsulotomy in Cataract Complicated With Primary Posterior Capsule Opacification.

Sponsor
Zhongshan Ophthalmic Center, Sun Yat-sen University (Other)
Overall Status
Unknown status
CT.gov ID
NCT03701139
Collaborator
(none)
40
1
2
3.7
10.7

Study Details

Study Description

Brief Summary

This is a two-arm, parallel group, open-label, randomized controlled trial to compare the visual acuity, visual quality, operative complications and the satisfaction of patients between primary posterior capsulorhexis group and laser capsulotomy group of cataract patients combined with primary posterior capsular opacification (PPCO).

Condition or Disease Intervention/Treatment Phase
  • Procedure: posterior capsulotomy
  • Procedure: laser capsulotomy
N/A

Detailed Description

Primary posterior capsular opacification (PPCO) refers to the posterior capsule opacification which cannot be removed by polishing or vacuuming during cataract surgery. The surgeon may have to decide on primary posterior capsulorhexis or early neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy in these cases. The aim of this study is to compare the visual acuity, visual quality, operative complications and the satisfaction of patients between primary posterior capsulorhexis group and laser capsulotomy group of cataract patients combined with primary posterior capsular opacification (PPCO).

Study Design

Study Type:
Interventional
Anticipated Enrollment :
40 participants
Allocation:
Randomized
Intervention Model:
Parallel Assignment
Masking:
Single (Outcomes Assessor)
Primary Purpose:
Treatment
Official Title:
Phacoemulsification Combined With Posterior Capsulotomy in Cataract Complicated With Primary Posterior Capsule Opacification: a Randomized Controlled Trial
Actual Study Start Date :
Oct 10, 2018
Anticipated Primary Completion Date :
Feb 1, 2019
Anticipated Study Completion Date :
Feb 1, 2019

Arms and Interventions

Arm Intervention/Treatment
Experimental: posterior capsulotomy

Primary posterior capsulotomy will be performed to remove the primary posterior capsule opacification after posterior capsule polishing during phacoemulsification.

Procedure: posterior capsulotomy
After phacoemulsification with intraocular lens implantation, primary posterior capsulotomy will be performed to remove the primary posterior capsule opacification after posterior capsule polishing. A limited anterior vitrectomy will be performed if the anterior hyaloid surface is broken.

Active Comparator: Nd:YAG laser capsulotomy

Nd:YAG laser capsulotomy will be performed 1 month postoperative to remove the primary posterior capsule opacification.

Procedure: laser capsulotomy
A routine phacoemulsification with intraocular lens implantation is performed. Then the Nd:YAG laser capsulotomy will be performed 1 month postoperative to remove the primary posterior capsule opacification.

Outcome Measures

Primary Outcome Measures

  1. LogMAR visual acuity 1 month postoperatively [1 month]

    Best corrected visual acuity (LogMAR) will be measured 1 month postoperatively.

Secondary Outcome Measures

  1. Dysfunctional lens index (DLI) [3 months]

    The dysfunctional lens index (DLI) is an objective lens performance metric derived from internal higher order aberrations (HOAs), pupil size, and contrast sensitivity data. DLI is a score ranged from 0 to 10. DLI will be measured by iTrace aberrometer.

  2. Internal higher order aberration (HOAs) [3 months]

    TInternal higher order aberration (HOAs) in micrometer can quantify the intraocular optical quality and will be measured by iTrace aberrometer.

  3. Object scatter index (OSI) [3 months]

    Object scatter index (OSI) is a ratio of 12 and 20 points from the perspective of the annular region of the light and the central 1 point perspective peak. OSI can objectively evaluate the amount of intraocular scattering and is an important index of optical quality. OSI is a score ranged from 0 to 10 and will be measured by Optical Quality Analysis System (OQAS).

  4. Modulation transfer function cut off (MTF cut off) [3 months]

    Modulation transfer function cut off (MTF cut off) relates directly to retinal image quality and is a useful indicator of visual performance in cataract eyes. MTF cut off will be measured by OQAS.

  5. Strehl ratio (SR) [3 months]

    Strehl ratio (SR) is computed as the ratio between the areas under the MTF curve of the measured eye and that of the aberration-free eye, and therefore it provides more global information on the optical quality. SR is a score ranged from 0 to 1 and will be measured by OQAS.

  6. Predicted visual acuity (PVA) with contrasts of 100%, 20% and 10% [3 months]

    Predicted visual acuity (PVA) with contrasts of 100%, 20% and 10% correspond to three specific frequencies of the MTF that describe the eye's optical quality for the contrast values mentioned. In general, PVAs higher than 1 are associated to very high retinal image quality. PVA will be measured by OQAS.

  7. Rate of ocular hypertension [3 months]

    Diagnosis of ocular hypertension is based on IOP greater than 21 mm Hg and the rate of ocular hypertension is calculated.

  8. Rate of ocular macular edema [3 months]

    The central macular thickness in micrometer is measured by optical coherence tomography (OCT) and the rate of ocular macular edema is calculated.

  9. Rate of retinal detachment [3 months]

    Retinal detachment following surgical or laser posterior capsulotomy is documented and the rate of Retinal detachment is calculated.

  10. Rate of intraocular lens damage [3 months]

    The rate of intraocular lens damage by Nd:YAG laser is documented.

  11. Visual-functioning index 7 score [3 months]

    Subjective satisfaction of patients is investigated by visual-functioning index 7 (VF-7) questionnaire. The VF-7 questionnaire comprises 7 questions for performing daily-life activities (1= a great deal of difficulty; 2= a moderate amount difficulty; 3= a little difficulty; 4= no difficulty). The VF-7 score is the average score of these 7 activities multiplied by 25, to give a final score between 0 and 100. nighttime driving; reading small print; watching television; seeing steps, stairs, or curbs; reading traffic, street, or store signs; cooking; doing fine handwork

Eligibility Criteria

Criteria

Ages Eligible for Study:
18 Years and Older
Sexes Eligible for Study:
All
Accepts Healthy Volunteers:
No
Inclusion Criteria:
  1. Cataract patients with primary posterior capsular opacification, which involves the central posterior capsular and interferes with visual axis;

  2. Aged 18 years or over;

  3. With best corrected visual acuity (BCVA) less than 0.3.

Exclusion Criteria:
  1. History of other eye disease that contributes to visual impairment, including keratopathy, uveitis, glaucoma, retinopathy, ocular trauma, or intraocular surgery.

  2. Cases with operative complications, including anterior or posterior capsular rupture, lens suspensory ligament rupture, the falling of lens nucleus into vitreous cavity.

  3. Unwillingness to participate in the study.

Contacts and Locations

Locations

Site City State Country Postal Code
1 Zhongshan Ophthalmic Center, Sun Yat-sen University Guangzhou Guangdong China 510060

Sponsors and Collaborators

  • Zhongshan Ophthalmic Center, Sun Yat-sen University

Investigators

  • Principal Investigator: Yizhi Liu, PhD, Zhongshan Ophthamic Center,Sun Yet-san University

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.
Responsible Party:
Yizhi Liu, Clinical Professor,director of Zhongshan Ophthalmic Center, Zhongshan Ophthalmic Center, Sun Yat-sen University
ClinicalTrials.gov Identifier:
NCT03701139
Other Study ID Numbers:
  • 2018KYPJ103
First Posted:
Oct 9, 2018
Last Update Posted:
Oct 17, 2018
Last Verified:
Oct 1, 2018
Studies a U.S. FDA-regulated Drug Product:
No
Studies a U.S. FDA-regulated Device Product:
No
Keywords provided by Yizhi Liu, Clinical Professor,director of Zhongshan Ophthalmic Center, Zhongshan Ophthalmic Center, Sun Yat-sen University
Additional relevant MeSH terms:

Study Results

No Results Posted as of Oct 17, 2018