EyeWorld India June 2015 Issue

3 EWAP CONTENTS June 2015 Dear Friends W elcome to another edition of the EyeWorld Asia- Pacific . This issue deals with pseudophakic presbyopic correction which continues to be a problem for patients and ophthalmologists. Nowadays, multiple options are available to treat pseudophakic presbyopia, though it is difficult to meet the demands and expectations of patients. The current treatments are multifocal IOLs, accommodating IOLs, monovision, and hybrid monovision. MFIOLs are a good option for the motivated patient. Disadvantages include reduced contrast sensitivity and increased glare. Monovision is induced anisometropia where we set the dominant eye for distance vision and the nondominant eye for near vision which is achieved by either contact lenses or monofocal ablation refractive surgeries. The pitfalls associated with monovision are diminished contrast sensitivity and binocular acuity. This edition also throws light on the various keratoplasty options available, such as PK, DSEK , DSAEK, and DALK. Keratoplasty refers to the replacement of the host cornea with a donor cornea either entirely or just a layer of it depending upon the procedure being perfomed. These procedures are performed for reduced visual acuity secondary to corneal opacity, in the treatment of corneal thinning or perforation, and for the removal of non-responsive infectious foci. Indications for keratoplasty include pseudophakic bullous keratopathy, aphakic bullous keratopathy, corneal degenerations and dystrophies, non-infectious ulcerative keratitis , microbial keratits including fungal and bacterial infectious keratitis, congenital opacities, chemical injuries, mechanical trauma, and regraft unrelated to allograft rejection. In the postoperative period, one should always watch for the following complications: Wound leak, endopthalmitis, primary endothelial failure, persistent epithelial defect, microbial keratitis, late failure corneal graft rejection. I hope you enjoy reading this issue. I look forward to meeting you all in Malaysia for the upcoming APACRS. As always I would want to end with a few lines from Thirukkural : What good does a man of wisdom obtain If he treats not others’ woes as his own? - Thirukkural 315 A man’s knowledge is of no use if he does not regard the sufferings of others as his own. Warmest Regards, S. Natarajan, MD Regional Managing Editor EyeWorld Asia-Pacific Letters from the Editors Dear Friends O ver the many years I have had the privilege of being the Editor of EyeWorld Asia-Pacific , the one topic that remains as relevant as ever is the options available to provide unaided near vision following cataract surgery. In this issue we cover the different intraocular lenses and strategies comprehensively. Multifocal IOLs are widely used and have been considerably refined since they were first introduced. Traditionally, the percentage of patients achieving total spectacle independence had been the primary criteria on which the success of a particular implant was judged but there now appears to be increasing recognition of the importance of intermediate vision and the recognition that the link between spectacle independence and patient satisfaction are not always intimately linked. Trifocal implants and low add diffractive bifocal implants sacrifice reading ability but address the deficiency of conventional diffractive bifocal intraocular lenses with regard to intermediate acuity. Similarly, extended depth of focus IOLs offer excellent intermediate acuity but often require the addition of a modest level of myopia in one eye similar to modest monovision to provide spectacle independence for reading. There is always a balance in how much total light energy can be split into multiple foci or extended with an extended depth of focus approach before there is an impact on the quality of vision and contrast sensitivity. Similarly reducing the number of diffractive rings does assist in reducing unwanted symptoms such as light scatter but it is not clear that one can achieve the superb quality of a monofocal lens with existing multifocal and extended depth of focus technology. Although our ability to achieve emmetropia following cataract surgery continues to improve, refraction change and the development of against-the- rule astigmatism is not unusual with the passage of time. Together with an inevitable decline in macula function, these factors can impact the efficacy of multifocal implants as patients age. Accommodative lenses remain seductive but despite some encouraging new technologies a predictable accommodative lens remains elusive. Modest monovision, which is personally my preferred approach, remains a practical solution and is widely practiced. Limiting defocus to approximately 1.25 D preserves stereoacuity and minimizes the asthenopia of traditional monovision resulting in a high level of patient satisfaction. The compromise with modest monovision is that spectacles are occasionally required for demanding near visual tasks but the ability to reverse the correction with spectacles at any time that it proves necessary to do so remains attractive. All these factors need to be taken into account when counseling patients and selecting the most appropriate intraocular lens to address the need for improved unaided near vision after cataract surgery. Although many of the currently available options discussed in this issue are similar to what has been published previously, it is encouraging to see refinements in existing technology as well as the availability of new intraocular lenses that were not available previously. I’m sure all the readers of this issue will find the discussions and opinions of expert surgeons, particularly from the Asia- Pacific region interesting and thought provoking. Warmest regards Graham Barrett Chief Medical Editor EyeWorld Asia-Pacific