O.O. Olawoye1, A.O. Ashaye1, C.O. Bekibele1 and B.G.K. Ajayi2
- Department of Ophthalmology, University College Hospital Ibadan, Nigeria.
- Ojulowo Specialist Eye Centre, Mokola Ibadan.
Aim: The aim of this study was to determine the visual outcome of patients who had cataract surgery in the University College Hospital Ibadan.
Methodology: This is an observational descriptive, longitudinal study of consecutive patients undergoing cataract surgery at the University College Hospital conducted between May and October 2007. A total of 184 patients who presented to the hospital and met the inclusion criteria were recruited into the study. Patients were examined preoperatively, 1st day postoperatively and 8th week postoperatively.
Results: The mean age was 66.5 years; and the male to female ratio was 1.2:1. Preoperatively, 137 patients (74.5%) were blind in the operated eye, while 39 patients (23.6%) were blind in both eyes at presentation. At 1st day postoperatively, 87 patients (47.3%) had pinhole visual acuity of 6/6-6/18. Best corrected vision after refraction eight weeks postoperatively showed that 127 patients out of 161 patients (78.8%) had good vision while 28 patients (17.4%) had borderline vision, and six patients (3.8%) had severe visual impairment after refraction. The number of bilaterally blind patients also reduced from 39 (23.6%) to one (0.6%). Uncorrected refractive error was the commonest cause of poor vision prior to refraction. Glaucoma was the commonest ocular co-morbidity accounting for poor vision in 9.1% of patients eight weeks after cataract surgery.
Conclusion: This study demonstrates that good results can be obtained with cataract surgery and intraocular lens implantation in the developing world. More attention should be directed towards ensuring that successful outcomes are indeed being realized by continued monitoring of postoperative visual outcomes and prompt refraction for all patients.
Keywords: Cataract, Visual outcome, Cataract surgery
Dr. Olusola O. Olawoye
Department of Ophthalmology,
University College Hospital Ibadan,
Cataract is the main cause of avoidable blindness worldwide, with the developing world accounting for three – quarters of this blindness.1 The Nigerian national survey of blindness found that cataract was responsible for 50% of blindness in Nigeria.2 In 1997 approximately 10million cataract operations were performed globally but despite this, cataract blindness is thought to be increasing by 1–2 million/year.3 To address this increasing backlog, significant progress is being made in increasing the output of cataract surgical services in many developing countries.4 Cataract control programmes have been established at both local and national levels to reduce the backlog of cataract blindness. These programmes are designed to increase the number of cataract operations and it is assumed that each case operated is a case of restored vision.
However it is becoming evident that the outcome of cataract surgery is not always as good as previously assumed, and much more attention needs to be given to this aspect of surgical services.5 Recent population based studies in Nepal,6 China,7 and India,8 show that 40–75% of people who have had cataract surgery have a presenting visual acuity of worse than 6/18 in the operated eye, and 21–53% have less than 6/60.
The aim of this study was to determine the visual outcome of patients who had cataract surgery in a tertiary hospital in South Western Nigeria, and to identify reasons for poor outcome.
This was an observational, descriptive, longitudinal study of consecutive patients who presented to the Eye clinic, UCH between May and October 2007. The Ophthalmology department of the hospital has a vibrant cataract outreach programme. This outreach programme was set up to increase cataract surgery rates. It has an outreach team which consists of all cadres of eye care workers. The outreach team reaches out to neighbouring communities and states to provide primary eye care services at different designated centres within the community and to refer patients who need more comprehensive eye care to the base hospital (UCH). lt was conducted among adults aged 40 years and above who had visually disabling cataracts.
A total sample of all consecutive, eligible patients who met the inclusion criteria and presented with operable cataract to the hospital within the study period were included. The inclusion criteria were patients who were 40 years and above coming for the first-eye cataract surgery. Patients with traumatic cataracts and those who had cataract surgery for cosmetic reasons were excluded from the study. These patients were excluded because they already had poor prognosis for vision prior to surgery. All surgeries were performed by consultants and senior residents. Most of the surgeries were extracapsular cataract surgery with posterior chamber intraocular lens implantation (ECCE+ PCIOL) and a few were small incision cataract surgery with posterior chamber intraocular lens implantation(SICS+PCIOL). All surgeons were monitored using the cataract surgical outcome monitoring system. In this system, a cataract record form is filled for every patient admitted for cataract surgery. Individual verbal informed consent was obtained from each participant. The study protocol was approved by the Ethical Review Board of the University College Hospital and University of Ibadan. Patients were studied prospectively over an eight week period and data was collected preoperatively, first day and eight weeks postoperatively. Preoperatively, a pretested structured questionnaire was administered to assess the socio-demographic data of each patient and the presenting pre operative visual acuity unaided and with pinhole in both eyes was recorded. Visual acuity test was done by two trained assistants using the illuminated Snellens chart. Visual outcome was categorized using the World Health Organization9 (W.H.O) standard where good vision is 6/6 to 6/18, borderline vision is less than 6/18 to 6/60 and poor vision is less than 6/60. Their postoperative visual acuities (aided and unaided) on the 1st day and eight weeks post-operation were recorded. Refraction was done for patients at eight weeks post-operation. Patients were followed up for eight weeks in this study because of time constraints and to reduce the number of patients lost to follow up (attrition rate). Data collected was entered in a data base and analyzed using SPSS (Statistical Package for Social Sciences) version 13. Analysis by percentages was used whenever appropriate.