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Distance Vision, Near Vision and Quality of Life Between Preferred Emmetropia and Residual Myopia in Monofocal Intraocular Lens Implantation - a Comparative Study

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Distance Vision, Near Vision and Quality of Life Between Preferred Emmetropia and Residual Myopia in Monofocal Intraocular Lens Implantation - a Comparative Study 10-Comparative00212_3-PRIMARY.qxd 5/13/21 10:29 PM Page 340 ORIGINAL ARTICLE Distance vision, near vision and quality of life between preferred emmetropia and residual myopia in monofocal intraocular lens implantation - A Comparative study Jaafar Juanarita, MMed 1,2,3 , Abdul Rahman Siti-Khadijah, MBBS 1,2 , Bakiah Shaharuddin, PhD 4, Yaakub Azhany, MMed 1,2 1Department of Ophthalmology and Visual Sciences, School of Medical Sciences, Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia, 2Ophthalmology Clinic, Hospital Universiti Sains Malaysia, Kubang Kerian, Kelantan, Malaysia, 3Hospital Sultanah Bahiyah, Alor Setar, Alor Setar, Kedah, 4Advanced Medical and Dental Institute, Universiti Sains Malaysia, Kepala Batas, Penang, Malaysia unoperated cataracts. 2 Currently, there is no effective ABSTRACT prevention for cataracts, and the only treatment is to remove Introduction: This study was done to evaluate the visual the cloudy lens. 3 acuity and quality of life in predicted emmetropia (EM) and predicted residual myopia (RM) patients following Intraocular lens (IOL) implantation is the commonest phacoemulsification with monofocal intraocular lens practice of visual rehabilitation after cataract surgery. implantation. Monofocal or fixed focal IOLs have only one focus at distance; thus, the placement of a monofocal IOL requires Materials and Methods: This prospective comparative study corrective lenses (spectacles) after surgery for near vision- was conducted in the ophthalmology clinic of the Universiti related tasks. Although no statistical difference was found Sains Malaysia Hospital, Kelantan, Malaysia. Overall, 139 between multifocal (MFIOL) and monofocal IOL with respect patients with senile cataract were randomised into EM and to achieving a post-operative best-corrected visual acuity RM groups. At three months post-operatively, patients were (BCVA) of 6/6, near vision was often found to be better with assessed for distance and near vision, as well as quality of MFIOL. 4 However, MFIOL is costly and would be a luxury for life using a modified VF-14 questionnaire. most people in poor and developing countries. In the Malaysian set up, monofocal IOL is still more popular than Results: Thirty-six patients (64.3%) in the EM group and 30 multifocal partly because it is more affordable. The final patients (52.6%) in the RM group (p = 0.209) showed good refractive result depends on the accuracy of biometric data distance vision (LogMAR 0.3 or better). Fifty patients (87.7%) and the appropriate use of IOL power calculations. 5 The in the RM group and 27 patients (48.2%) in the EM group target for residual refractive result post-operative slightly gained significantly higher satisfactory near vision (p < varies among ophthalmologist. Some ophthalmologists 0.05). The quality of life in both groups was good, with a recommend emmetropia, while others routinely prefer mean modified VF-14 score of 94.5 (SD 2.68) for the EM residual myopia up to −1.00 dioptres (D). 6 However, there is group and 95.1 (SD 3.19) for the RM group (p = 0.286). still lack of evidence on the impact of these target final Female patients scored significantly higher than males for refractive result post-operative to the quality of life of the total activities (p = 0.010) and distance vision-related patients. activities (p = 0.001). The RM group had significantly better patient satisfaction for near vision-related activities The post-operative outcome of functional vision is classified compared to the EM group (p = 0.001). In particular, the item according to both objective and subjective findings. Objective ‘reading small print’ was significantly better in the RM group parameters include uncorrected visual acuity, contrast (p = 0.003). sensitivity, glare disability, visual field and colour vision. Subjective parameters are best evaluated through interviews Conclusion: Patients in the predicted RM group gained more or questionnaires since the domains covering daily activities satisfactory near vision than patients in the EM group, with can be tailored to local populations. Several questionnaires significantly better quality of life for near vision activities. are available for this purpose, such as the Visual Function Index 14 (VF-14) 7,8,9 , European Quality of Life 5 Dimensions KEYWORDS: Quality of life, post-cataract operation, residual myopia, near (EQ-5D) questionnaire, 10 the National Eye Institute Refractive vision Error Quality of Life Instrument-42 (NEI RQL-42), 11 and the Glasgow Benefit Inventory. 12 VF-14 questionnaire is a self- reported outcome-based questionnaire which was initially designed for cataract patients. However it has now been INTRODUCTION Cataract is the main cause of preventable blindness widely used in glaucoma, retina and corneal diseases. It has worldwide, contributing to 51% of the total incidence. 1 In been modified to include activities that are more relevant to Malaysia, 58.6% of preventable blindness cases are caused by the local population in other languages. 13,14 This This article was accepted: 28 March 2021 Corresponding Author: Azhany Yaakub Email: [email protected] 340 Med J Malaysia Vol 76 No 3 May 2021 10-Comparative00212_3-PRIMARY.qxd 5/13/21 10:29 PM Page 341 A Comparative study questionnaire was translated into Bahasa Malaysia and Implantation of a monofocal IOL (AcrySof IQ SN60WF, Alcon Malaysian activities such as reading fine print such as Laboratories Inc., Forth Worth, Texas, USA) was performed Quran, sewing, wood carving and carpentry were added. The by three ophthalmologists. modified Malaysian VF-14 questionnaire has been used by previous authors. 15 VF-14 was preferred due to the simple Data collection format and easily administered thus increasing patient Post-operative exclusion criteria included any intra operative compliance. or post-operative complications, spherical equivalent differing from predictive refractive power more than + 0.50 D This study was aimed to evaluate the visual acuity and and astigmatism more than -2.00D either pre-existing quality of life (QOL) in predicted emmetropia (EM) group and preoperatively or surgically induced postoperatively. At predicted residual myopia (RM) group following 10–12 weeks post-operatively, patients were interviewed for phacoemulsification with monofocal IOL using a modified demographic data, followed by evaluation for distance vision VF-14 questionnaire. The VF-14 is used for the assessment of using a LogMAR chart. Patients with a LogMAR of 0.3 or QOL in post-operative cataract patients. A previous study better were grouped as ‘satisfactory distance vision’, and suggested that VF-14 is a dependable and effective measure those with a LogMAR of less than 0.3 were grouped as ‘non- of QOL. 16 This study compares EM and RM with QOL as a satisfactory distance vision’. Subjective refraction using Red measure of the functional vision post-phacoemulsification green filter, Jackson Cross Cylinder and Binocular Balancing with IOL implantation. was performed to obtain the BCVA and spherical equivalence. Near vision was checked using a Jaeger chart. Patients who scored J3 or better were grouped as ‘satisfactory near vision,’ and those who scored less than J3 were grouped MATERIALS AND METHODS Patients as ‘non-satisfactory near vision’. 17 A total of 139 patients were selected for this study. Patients were recruited from the eye clinic of the Universiti Sains QOL (modified VF-14 questionnaire) Malaysia Hospital, Kubang Kerian, Kelantan, Malaysia. Post-operative QOL evaluates the perception of the Ethical approval was obtained from the Ethical Research effectiveness of their surgery of patients via the use of a Committee of the Universiti Sains Malaysia. Written consent health related QOL questionnaire. This study used a modified was obtained from the participants. All senile cataract Bahasa Malaysia version VF-14 questionnaire which assessed patients undergoing phacoemulsification with monofocal the post-operative satisfaction of the patients with their IOL were enrolled in the study. The predictive refractive visual function in three domains: near, intermediate and power of intraocular lens selection was done by simple distance. The questionnaire was modified from English to randomization method. The patients were divided into two Malaysian, and some activities relevant to the local groups using closed envelope method. They were given an population were added. A score was given with a scale of 0 to envelope containing a paper written either Group A or Group 100. Scores on all activities that the patients could perform or B. Group A (predicted emmetropia) were patients that using could not perform were then averaged, yielding an average intraocular lens with predicted refractive power of 0.00 to - score between 0 and 4. This average score was then 0.50 D and Group B (predicted residual myopia) were multiplied by 25, resulting in a possible final score ranging patients that using IOL with predicted refractive power of - from 0 (unable to do all applicable activities due to vision 0.51 to -1.00D. At 6 weeks post-operatively, distance and near problems) to 100 (able to do all applicable items without vision were recorded, and questionnaires were given to difficulties). Patients with a VF-14 score between 95.01 and evaluate patient QOL. 100.00 were considered ‘satisfied’, while those who had a VF- 14 score of 95.00 or less were considered ‘not satisfied’. For Clinical evaluation individual items, patients who scored 4 were considered Patients were subjected to full
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