Clinical Investigation of the Bi Flex M Multifocal IOL

Randomised Clinical Investigation of the Bi Flex M Multifocal Intraocular Lens

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.

Inclusion Criteria:

• 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

Exclusion Criteria:

• 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