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Completed

NCT Number: NCT03674840

Comparison of Optical Quality With Different Placement of Refractive Multifocal Intraocular Lens

The study aims to compare postoperative optical quality between two different implanting position of a rotationally asymmetric MIOL [SBL-3 Lenstec; +3.00 diopters (D)], angle kappa based implantation and 0 to 180 degree implantation, in order to find out the optimal implantation position for SBL-3.

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Key information

Conditions

Cataract, Age-Related Cataract Eye Diseases Lens Diseases

Age range

54 year–81 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Peking University Third Hospital

Beijing, Beijing Municipality, 100191, China

About this study

SBL-3 has been proved to provide patients with good near, intermediate and distant visual acuity, but there is not much study on the impact of SBL-3 position on postoperative visual acuity.The regional refractive design of SBL-3 means it could be affected by pupil center shift (described by angle kappa: the difference between visual axis and pupil axis), the investigators assume that maintaining the ideal ratio of distant and near segment(50% vs 42%) in the pupil center could yield both good distant and near postoperative visual acuity postoperatively. Therefore, the investigators designed the implantation by placing the IOL based on angle kappa to make sure the ratio of distant and near segment exposure in the pupil center close to 50:42. In this study, the investigators assessed the optical quality in patients with SBL-3 implantation based on angle kappa and 0 to 180 degree to provide surgeons with information for choosing appropriate implantation position for optimum postoperative satisfaction of SBL-3.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • age related cataract
  • underwent bilateral cataract surgery and SBL-3 implantation
  • corneal astigmatism <1.5D

Exclusion criteria

  • patients with active ocular inflammation
  • neuro-ophthalmic disease and macular disease
  • previous corneal or intraocular surgery, corneal opacities or disease
  • patients had surgical complications, pupillary trauma, inability to place the lens in the capsular bag
  • IOL tilt or decentration deviated from intraoperative positioning
  • difficulties with examinations and follow-up

Treatment and study plan

angle kappa based SBL-3 implantation

Procedure

SBL-3 implantation based on kappa angle guided by Callisto Eye System(Carl Zeiss Meditec, Germany) intraoperatively.

0 to 180 degree SBL-3 implantation

Procedure

SBL-3 implantation in the direction of 0 to 180 degree guided by Callisto Eye System(Carl Zeiss Meditec, Germany) intraoperatively.

Primary outcomes

  1. Uncorrected visual acuity

    Time frame: 3 months postoperatively

    Comparison of uncorrected distance visual acuity (UCVA), intermediate visual acuity, near visual acuity were measured at 5m, 80cm and 33cm respectively. All visual acuity measurements were conducted under photopic conditions (85 cd/m2) and at 100% contrast in design group and control group.

Secondary outcomes

  1. Optical quality

    Time frame: 3 months postoperatively

    An OPD scan III aberrometer (NIDEK Co. Ltd., Gamagori, Japan) was used to evaluate postoperative mesopic and photopic pupil diameters and the quality of vision in each subject. Visual acuity was evaluated by MTF(modulation transfer function), SR(strehl ratio), intraocular total aberration, high order aberration, spherical aberration, coma aberration, trefoil aberration under 4mm pupil diameter.

  2. Contrast sensitivity

    Time frame: 3 months postoperatively

    Contrast sensitivity measures were conducted uniocularly, under photopic, mesopic (5 cd/m2), photopic with glare and mesopic with glare conditions, with the OPTEC 6500 contrast sensitivity test (Stereo Optical, USA). Contrast sensitivity was evaluated at five spatial frequencies (1.5, 3, 6, 12, and 18 cycles per degree [cpd]). Patients were allowed 5 minutes to adapt to each illumination level before testing.

  3. Defocus curve

    Time frame: 3 months postoperatively

    Monocular defocus curves were obtained in all patients, positioned at 5m under photopic (>85 cd/m 2 ) condition to measure the visual acuity with each defocus lens, representing the consecutive visual function of each eye. Negative lenses were added in 0.50 D steps and the visual acuity was recorded for each type of defocus level. The procedure was then repeated but with positive lenses. The range of defocus evaluated was from -4.00D to +2.00D.

Sponsors and collaborators

Lead sponsor

Peking University Third Hospital

Other

Registry information

Important dates

Study start
2017
Primary completion
2019
Study completion
2019
First posted
Sep 18, 2018
Registry last updated
Aug 5, 2022

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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