Clinical Investigation of the Bi Flex M Multifocal IOL
- Conditions
- Cataract
- Interventions
- Device: Bi flex 1.8 monofocal intraocular lensDevice: Bi flex M multifocal intraocular lens
- Registration Number
- NCT02338882
- Lead Sponsor
- Dr Phillip J Buckhurst
- Brief Summary
During cataract surgery an artificial lens is implanted in the eye. These artificial lenses are called intraocular lenses (IOLs) and there are many different types of IOL designs. IOLs are of fixed focus and so unless a multifocal IOL is used you would need to wear spectacles for viewing near objects. This study has been designed to look at how well a multifocal IOL corrects distance and near vision in comparison with a conventional monofocal IOL. Both types of IOLs are commercially available and are commonly implanted. Using new non-invasive methods we hope to be able to better judge the visual performance of these IOLs. In addition the study will involve imaging and examining the IOLs to determine the prevalence of any post-operative complications.
- Detailed Description
Not available
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- All
- Target Recruitment
- 100
- Age related cataract patients requiring cataract surgery with phacoemulsification.
- Patients requiring primary IOL implantation
- Patients with a potential corrected visual acuity of 20/40 or better on clinical assessment
- Patients with normal anterior segments apart from cataracts
- Subjects with clear intraocular media other than cataract
- Preexisting pathology or physiology, which may be aggravated by the implant, or may render the implant ineffective and that could potentially cause future acuity losses to a level of 0.5 or 20/40 or worse in either eye. This includes the following:
- Microphthalmia
- Corneal decompensation or Endothelial Insufficiency
- Pseudo exfoliation
- High myopia
- Pars planitis
- Patient with greater than 1 dioptre of preoperative corneal astigmatism
- Subjects who are expected to require retinal laser treatment
- Previous intraocular and/or corneal surgery
- History of uveitis, glaucoma, proliferative diabetic retinopathy, pseudoexfoliation, macular degeneration that may affect potential best corrected visual acuity of 20/40 or better
- Operative complications of posterior capsular rupture, zonular dehiscence, incomplete continuous curvilinear capsulorhexis, severe iris /corneal trauma and inability to achieve secure placement in the designated location
- Subjects using a systemic medication that is known to cause ocular side effects
- Subjects participating in a concurrent clinical trial or if they have participated in an ophthalmology clinical trial within the last 30 days
- Subjects who have only one eye with potentially good vision
- Patients who are not willing to cooperate for the follow up period
- Visual eccentricity of greater than 0.7mm
- Pregnant women
- Patients where it is not possible to take informed consent
Study & Design
- Study Type
- INTERVENTIONAL
- Study Design
- PARALLEL
- Arm && Interventions
Group Intervention Description Bi flex 1.8 monofocal intraocular Bi flex 1.8 monofocal intraocular lens Subjects implanted bilaterally with the Bi flex 1.8 monofocal intraocular lens Bi flex M multifocal intraocular lens Bi flex M multifocal intraocular lens Subjects implanted bilaterally with the Bi flex M multifocal intraocular lens
- Primary Outcome Measures
Name Time Method Monocular Visual Acuity (VA) Visit 1 [3-6 months] Monocular Visual acuity at 3-6 months assessed at distance intermediate and near both corrected and uncorrected. Assessed in LogMAR
Long Term Monocular Visual Acuity (VA) Visit 2 [12-18 months] Monocular Visual acuity at 12-18 months assessed at distance intermediate and near both corrected and uncorrected. Assessed in LogMAR
Binocular Visual Acuity (VA) Visit 1 [3-6 months] Binocular Visual acuity at 3-6 months assessed at distance intermediate and near both corrected and uncorrected. Assessed in LogMAR
Defocus Curve Profiles visit 1 (3-6 months) Visual acuity measurement (assessed in LogMAR) taken with differing levels of optical defocus
Long Term Defocus Curve Profiles visit 2 (12-18 months) Assessed as a dioptric range and using the Defocus area metric
Long Term Binocular Visual Acuity (VA) Visit 2 [12-18 months] Binocular Visual acuity at 12-18 months assessed at distance intermediate and near both corrected and uncorrected. Assessed in LogMAR
- Secondary Outcome Measures
Name Time Method Long Term Monocular Pelli-Robson Contrast Sensitivity (CS) Visit 2 [12-18 months] MonocularContrast sensitivity assessed as a contrast threshold using the Pelli-Robson test
Pelli-Robson Binocular Contrast Sensitivity Visit 1 [3-6 months] Contrast sensitivity assessed as a contrast threshold using the Pelli-Robson test
Long Term Reading Performance Visit 2 (12-18 months) Assessed as the critical print size and using the reading performance index. Uses Radner reading chart and logarithmic Radner scale (LogRAD) Lower LogRAD equals smaller print size
Reading Performance visit 1 (3-6 months) Assessed as the critical print size and using the reading performance index Logarithmic Radner scale (LogRAD) Lower LogRAD equals small print size
Long Term Binocular Pelli-Robson Contrast Sensitivity (CS) Visit 2 [12-18 month] Binocular Contrast sensitivity assessed as a contrast threshold using the Pelli-Robson test
Pelli-Robson Monocular Contrast Sensitivity Visit 1 [3-6 months] Monocular Contrast sensitivity assessed as a contrast threshold using the Pelli-Robson test
Long Term Glare Visit 2 (12-18 months) Assessed as the glare area size Scale 0 to 100 Higher scores = larger glare area =worse outcome
Glare visit 1 (3-6 months) Assessed as the glare area size Scale 0 to 100 Higher score = larger area = worse outcome
Long Term Contrast Sensitivity CSV-1000 Visit 2 [12-18 months] Binocular Assessment of Contrast Sensitivity at threshold using the Contrast sensitivity vision(CSV) CSV-1000
Contrast Sensitivity CSV-1000 Visit 1 [3-6 months] Binocular Assessment of Contrast Sensitivity at threshold using the CSV-1000