Masters Degrees (Ophthalmology)

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The prevalence and severity of retinopathy in patients with coronary artery disease at a tertiary hospital in Durban, South Africa.
(2021) De Jager, Johannes Frederick.; Naidoo, Datshana Prakesh.; Visser, Linda.; Ponnusamy, Somalingum.
Background Studies have described the prognostic value of retinopathy in coronary artery disease (CAD) but few have examined the relationship between retinopathy and the CAD severity. Aim The study investigated the prevalence of retinopathy in CAD patients [acute coronary syndrome (ACS) and chronic stable CAD] and determined the association of retinopathy and other clinical factors with the extent of coronary artery disease as assessed by the number of epicardial vessels involved. Methods A cross sectional prospective study of 121 in-patients was undertaken over a ten-month period at Inkosi Albert Luthuli Central Hospital. One hundred and nine patients (12 stable CAD, 97 acute coronary syndrome) had angiographically confirmed CAD and the remaining 12 patients with normal angiograms served as controls. All participants had a comprehensive systemic evaluation and fasting biochemistry. Retinopathy was assessed using five to seven wide field fundus photographs. Macular thickness, vessel density and macular perfusion were assessed with optical coherence tomography (OCT) and OCT angiography. Results Compared to subjects with normal angiograms (controls), those with CAD had more frequent diabetes (67.9% vs 16.7%, p<0.001). Triple vessel disease (TVD) was present in 43.4% of diabetic patients compared to 35.6% of non-diabetics (p=0.004). Multivessel involvement was more frequent in diabetics (79%) compared to nondiabetics (58%), (p=0.002). xi The prevalence of any form of retinopathy was 66% in the CAD group and 33% in the control group (p=0.026). Subjects with double vessel disease (DVD) were more likely to have any form of retinopathy (77.8%) compared to those with single vessel disease (65.2%) and triple vessel disease (59.2%) (p=0.027). Diabetic retinopathy (DR) was present in 34 subjects (31.2%) in the CAD group and one subject (8.3%) in the control group (p=0.097). The majority of CAD patients with DR had non-proliferative diabetic retinopathy (NPDR) (n=29, 85.3%) and five (14.7%) had proliferative diabetic retinopathy (PDR). Patients with CAD and DR were more likely to have microalbuminuria compared to those without CAD and DR (p=0.014). An irregular foveal avascular zone (FAZ) was more frequent in the subgroup of CAD with diabetes (n=15) compared to the CAD without diabetes (n=1) group (21.3% vs 2.9%, p=0.013). In bivariate analysis, diabetes was strongly associated with having CAD and any form of retinopathy (OR = 0.238, CI = 0.109-0.517, p<0.001). Hypertensive retinopathy was present in 43 (40.2%) subjects in the CAD group and three (25%) in the control group (p=0.306). More than 60% of the CAD patients with HR had grade 2 retinopathy; only one CAD subject had grade 3 HR. Subjects with CAD and hypertensive retinopathy were more likely to be between the ages of 55-64 years (41.9%, p=0.016), to be smokers (p=0.034) and have the metabolic syndrome (p=0.004). Conclusion Retinopathy was a frequent finding in this sample group of predominantly ACS subjects and was associated with clustering of the major risk factors. The presence of DR, microalbuminuria and foveal abnormalities in diabetic subjects with CAD suggest underlying coronary microvascular disease. This study calls for surveillance of subjects with retinopathy to detect the presence of CAD.
The prevalence and severity of retinopathy in patients with coronary artery disease at a tertiary hospital in Durban, South Africa.
(2021) De Jager, Johannes Frederik.; Naidoo, Datshana Prakesh.; Ponnusamy, Somalingum.
Background Studies have described the prognostic value of retinopathy in coronary artery disease (CAD), but few have examined the relationship between retinopathy and CAD severity. Aim The study investigated the prevalence of retinopathy in CAD patients [acute coronary syndrome (ACS) and chronic stable CAD] and determined the association of retinopathy and other clinical factors with the extent of coronary artery disease as assessed by the number of epicardial vessels involved. Methods A cross-sectional prospective study of 121 in-patients was undertaken over a ten-month period at Inkosi Albert Luthuli Central Hospital. One hundred and nine patients (12 stable CAD, 97 acute coronary syndromes) had angiographically confirmed CAD, and the remaining 12 patients with normal angiograms served as controls. All participants had a comprehensive systemic evaluation and fasting biochemistry. Retinopathy was assessed using five to seven wide-field fundus photographs. Macular thickness, vessel density and macular perfusion were assessed with optical coherence tomography (OCT) and OCT angiography. Results Compared to subjects with normal angiograms (controls), those with CAD had more frequent diabetes (67.9% vs 16.7%, p<0.001). Triple vessel disease (TVD) was present in 43.4% of diabetic patients compared to 35.6% of non-diabetics (p=0.004). Multivessel involvement was more frequent in diabetics (79%) compared to nondiabetics (58%) (p=0.002).
An observational study on the outcome of corneal cross-linking for Keratoconus at Greys tertiary hospital, Pietermaritzburg.
(2018) Pupuma, Noluthando.; Kruse, Carl-Heinz.
The purpose of this observational study was to evaluate the efficacy of corneal cross-linking for keratoconus, beginning when the procedure was performed up to a year after the procedure in patients at Greys Hospital in Pietermaritzburg, South Africa between January 2010 and December 2015. Keratoconus is a progressive, non-inflammatory ectatic corneal disorder characterised by a progressive corneal thinning that causes irregular astigmatism and decreasing visual acuity. It is often associated with allergic conjunctivitis and seems to also have a degree of familial inheritance. Onset is during the first decade and is progressive until the third decade of life when it often seems to stabilise. Amongst the corneal ectatic diseases it remains the most common cause of debilitating progressive visual impairment during childhood and adulthood. Individuals with keratoconus form a significant proportion of patients for a practitioner specialising in corneal diseases, yet it is a disease in which the pathogenesis is poorly understood and until recently there has been no treatment (apart from corneal transplantation) that could be offered that was curative or capable of slowing the progression of the disease. Collagen cross-linking treatment using riboflavin and UV light was developed in an attempt to address this need and the initial results were promising. Charts from a sample of 54 eyes from 49 patients aged between 13 and 35 years with keratoconus treated once with corneal cross-linking, were reviewed from the time of the procedure until 1 year after the procedure or for three consecutive follow-up visits after the procedure. Although less successful than similar studies on Caucasian patients, there was significant stability in the keratometric and pachymetry measurements. The results show that the cross-linking procedure for keratoconus is a useful conservative treatment modality to stop the progression of keratoconus. This also means that the need for corneal graft procedures is significantly reduced. The fairly minimal costs involved in this procedure compared to corneal graft procedures are also an important point to consider. More study is required to elicit whether corneal cross-linking is less successful in African patients than in Caucasians.
A microscopic analysis of single-use versus multi-use Phacoemulsification tubing in maintaining sterility and patient safety.
(2018) Ndlovu, Lungile Thandeka.; Kruse, Carl-Heinz.
Cataract is first of the five most common causes of blindness and vision impairment (poor night vision, fading colours and haloes around light) worldwide. It is followed by glaucoma, macular degeneration, diabetic retinopathy and trachoma. Prevention of blindness remains one of the most important areas of research in the medical field. A blind person becomes a burden in the family and the community at large, and blindness also shortens life span. Cataract extraction with intraocular lens implant is the most common surgery worldwide. We live in a developing country where we need a balance between quality and safe health practises against cost-effective measures. We need to increase the number of cataract extractions in order to decrease vision impairment and blindness. At the same time, we need to find cost-effective ways so that this procedure does not deplete the health budget. One way of decreasing costs is to reuse equipment after cataract surgery. Cataract extraction has evolved over many years. It is one of the oldest surgical procedures, first documented in the fifth century BC. The most significant change which marked a modern era victory was the introduction of phacoemulsification (phaco) in 1967. Phacoemulsification involves the breakdown of the nucleus using ultrasonography, irrigation and aspiration of the lens material. This technique has fewer complications including less wound problems, the procedure is sutureless and the risk of endophthalmitis and suprachoroidal haemorrhage is significantly decreased. Two phacoemulsification tubes are connected to a phaco probe, one tube has fluid for irrigation and the other tube aspirates lens material and fluid. Both tubes do not enter the eye, only the probe does. The phaco probe can therefore not be reused without being first sterilised. The tubes, however, should remain sterile and could potentially be reused. This study looks particularly at the sterility of the irrigation tube which carries BSS (Balanced Salt Solution) to the eye. This observational descriptive prospective study was conducted at Edendale Hospital and Greys Hospital in the city of Pietermaritzburg (PMB). These hospitals are part of the PMB metropolitan complex in South Africa. In this complex there is no standard protocol with regards to whether we may reuse phaco tubing or not. Greys Hospital does not reuse tubing (they use one “phaco pack” per theatre case) whereas Edendale Hospital reuses the tubing: one tubing for 3 cases. For this study the tip of each tube was sent for culture to check for micro-organisms. Two unused phaco tubings were sent as controls. We used the same laboratory for all analyses. Guidelines from the manufacturer state that phaco packs (the tubing is found inside this pack) are for single use only (1). There is, however, lack of scientific proof to back this guideline. We endeavoured to assess whether reusing phaco tubing has a negative impact on the sterility (and therefore safety) or not. If not, then reusing the phaco tubes could be widely adopted in an effort to save money while maintaining patient safety. In summary, the aim of this observational descriptive prospective study is to assess if phacoemulsification tubing remains sterile during sequential phacoemulsification procedures. The objectives are to investigate whether there is a difference in growth of micro-organisms from phaco tubing that are used at the two sites; to investigate and compare micro-organisms, if identified, from each specimen; and to gather evidence for a future protocol regarding reusing phaco tubing for sequential phacoemulsification. More than half of all specimens in each group showed growth of the bacillus species and other organisms as a result of contamination. This study showed that there was a non-statistical difference between the contamination rates of the tubes from both hospitals. Although a statistical significance was not shown, this result is of great clinical significance. It highlights the need for further research into patient safety as our study showed significant contamination. Patient safety cannot be concluded from this study. A protocol to be followed by all the PMB complex hospitals cannot be drawn up as yet as further research into patient safety is warranted.
Bevacizumab in a treat-and-extend regimen for neovascular age related macular degeneration in a resource limited sector.
(2016) Le Roux, Etienne Philip.; Kruse, Carl-Heinz.
Abstract available in PDF file.
Simultaneous three or four horizontal rectus muscle surgery versus two-staged surgery for large angle congenital esotropia in children : a randomized controlled trial.
(2017) Du Bruyn, Magritha.; Zaborowski, Anthony Grant.
Large angle congenital esotropia is commonly seen in South Africa. The optimal surgical approach for angles larger than 50 prism dioptres (PD) esotropia is controversial. Conventional bilateral medial rectus muscle recessions used for smaller angles is not sufficient to achieve and maintain alignment in large angles. Large esotropias therefore either require very large medial rectus muscle recessions, or surgery on the medial rectus as well as one or both lateral rectus muscles. In the past supramaximal medial rectus recessions have been associated with late consecutive exotropia and other long term complications. Three or four horizontal rectus muscle surgery can be performed as one procedure or as staged surgery. In staged surgery the medial rectus muscles of both eyes are recessed, the residual angle measured and the lateral rectus muscles resected for the remaining deviation during a second procedure. One would expect the two procedure surgery to have greater accuracy with lateral rectus resections once the effect of the initial medial rectus recession surgery has been established. I could find no data comparing the outcome between one and two procedure surgery. KwaZulu-Natal is one of the largest provinces in South Africa and patients in rural areas need to travel long distances to the hospital. Financial resources are limited. I wanted to know how the outcome between a single three or four muscle procedure compares to a staged procedure. If the results are similar, a single procedure would save patients time and money, avoid exposure of the child to a second general anaesthetic and save valuable theatre time and resources. The purpose of this comparative study was to compare the outcome of a single three or four horizontal rectus muscle surgery to a staged procedure in children aged 9 months to 16 years with large angle congenital esotropia presenting to the Eye Clinic at Inkosi Albert Luthuli Central Hospital from March 2011 to July 2014. All children with congenital esotropia and angles larger than 50PD within the required age group who had not had previous strabismus surgery, significant refractive errors, amblyopia, eye pathology leading to poor vision or neurological problems were recruited for the study. Each child was randomly assigned to one of two treatment groups (one procedure or two procedure staged surgery 6 to 12 weeks apart). The surgery was performed by a single surgeon. The amount of rectus muscle surgery was based on standard of care surgical tables. Alignment in the two groups was compared 6 weeks after the final procedure. I hope that the results of this study would assist in optimizing the management of children with large angle congenital esotropia.
The knowledge of general practitioners in the Vaal Triangle concerning common eye diseases.
(2016) De Lange, Johannes Tobias.; Kruse, Carl-Heinz.
General Practitioners (GPs) are often the first clinician to be consulted regarding eye care problems. The incidence of avoidable visual impairment will increase significantly in the future raising concerns that the General Practitioner (GP) will be confronted even more with eye related complaints. Worldwide there is a tendency to decrease the amount of time spent in undergraduate training, in all smaller disciplines. Inadequate undergraduate training seems to leave a void in the knowledge of GPs concerning the management of primary eye care problems. Having been in Private GP Practice myself for five years and then starting to specialise, I realised that the undergraduate exposure to Ophthalmology is most probably insufficient. During my interaction with colleagues at a GP level, I found that this is a common feeling and that this contributed to uncertainty in treatment of patients with "eye problems”. This study aimed to examine the knowledge of GPs in the Vaal Triangle (Vereeniging, Vanderbijlpark and Sasolburg) regarding common eye diseases and to determine if any deficiencies in their knowledge existed. The second objective was to determine if a lack of knowledge regarding common eye diseases could be due to insufficient undergraduate training and to determine if a need to revise the curricula of the undergraduate ophthalmic programs of the various Universities exist. For a comprehensive revision of curricula, a complete examination of the contents and training methods should also be undertaken which is not the aim of this study. An observational descriptive cross-sectional study, utilising purposive sampling, was done by inviting all GPs in private practice in the Vaal Triangle area, registered with the Health Professional Council of South Africa (HPCSA) and the Board of Healthcare Funders (BHF), to participate. A questionnaire consisting of 10 primary care level ophthalmology questions, as well as questions to determine demographics and other variables, was emailed to each General Practitioner (GP). The questions were completed online by following a link provided in the email that was send. Most of the questions came from a similar study that was conducted in Cape Town by a different author. The response rate for this research project was 81.4% (79 out of 97 GPs). All eight South African universities with medical schools were represented in the research population. According to the feedback received 56.5% GP’s rated eye related complaints as 10% or more of their total workload. Alarmingly 44.3% GPs scored less than 50% in the questionnaire, yet 83% felt that the primary eye care should be done by the GP. The results further indicated that the longer the undergraduate rotation in the field of Ophthalmology, the better the performance is in terms of knowledge regarding primary eye care management. Duration in private practice did not contribute to better knowledge in the identification and management of eye related problems. Enhancing undergraduate training programmes for primary eye care may result in better clinical management of eye health by GPs.
Human immunodeficiency virus and CD4 count in ocular surface squamous neoplasia.
(2016) Jogi, Thenushka.; Kruse, Carl-Heinz.
During my time working at various eye clinics in Kwazulu-Natal, I observed that more often than not, patients with disfiguring ocular surface squamous neoplasia (OSSN) were Human Immunodeficiency virus (HIV) positive and generally quite ill, often requiring radical ophthalmic surgery for the tumour and urgent referral to the local Centre for Disease control (CDC) and HIV/Acquired Immunodeficiency Syndrome (AIDS) clinics, whereas the patients with conjunctival intraepithelial neoplasia (CIN) were usually HIV negative or HIV positive but well looking. This sparked the question of whether or not there may be a relationship between Cluster of Differentiation 4: a glycoprotein found on the surface of immune cells (CD4) counts and OSSN in HIV positive patients and could these findings – should they be in the affirmative – be used as a CDC case defining criteria for AIDS and streamlet referral of these patients for Highly Active Antiretroviral Therapy (HAART). Although HIV/AIDS is a global pandemic and has been linked to OSSN, an extensive literature search found no studies specifically looking at CD4 counts in these patients. My study titled “Human Immunodeficiency Virus and CD4 count in ocular surface squamous neoplasia” was thus born. I elected to perform my study in two parts. Firstly a prospective descriptive study to determine the prevalence of HIV in OSSN in my study population from September 2012 to December 2014, and secondly a case control study to determine the odds ratio of CD4 counts in HIV positive patients with OSSN (cases) and those without OSSN (controls) I hypothesized that: 1. >50% of patients with OSSN have HIV and 2. At least 90% of HIV patients with OSSN have a CD4 count <350 cells/μl. It was unfortunate that the number of cases recruited in the given time fell short of the ideal number required as outlined in my protocol, however a minimum of 3 controls per case (as opposed to one) all matched for age and gender were selected from the national data base in order to improve the statistical significance and proceed with the study. I had hoped that the results from this study could be used to include OSSN as a CDC case defining condition for AIDS but unfortunately, although illustrative of the possibility, larger studies will have to be conducted to prove this. I was however, able to achieve the listed aims of the study and prove both of the hypotheses. It is hoped that in doing so, the holistic management of these patients with OSSN will be improved with their referral for HIV and AIDS screening being streamlined and emphasized.
Outcomes following intravitreal bevacizumab for aggressive posteriorly located retinopathy of prematurity at a tertiary institution.
(2016) Jordaan, Thomas Johannes.; Visser, Linda.
Abstract available in PDF file.
Corneal ulcers : culture isolates and antibiotic susceptibility of microbial keratitis in KwaZulu-Natal, South Africa.
(2014) Dullabh, Viresh.; Kruse, Carl-Heinz.
Aim: To determine the causative organisms for corneal ulcers in patients in KwaZulu-Natal, culture positivity rates and antibiotic sensitivity for the organisms cultured. Method: A retrospective chart review of laboratory results of patients presenting with a corneal ulcer to St Aidan’s Hospital and Addington Hospital in Durban, KwaZulu-Natal for the year 2012. Twenty eight records were received from the NHLS. The following information was extracted: age, sex, microbial isolate and antibiotic sensitivity and resistance. Results: All specimens were culture positive, 3 showed mixed growth. Of the 31 organisms cultured 71% were Gram positive, 25.8% were Gram negative and 3.2% were fungal. Streptococcus pneumoniae (59%) and Staphylococcus aureus (22.7%) were the common Gram positive organisms, Pseudomonas was the most common Gram negative organism. Gram positive organisms were 100% susceptible to Cephalothin and Ciprofloxacin. Gram negative organisms were 88% (p = 0.53) and 100% susceptible to Tobramycin and Ciprofloxacin respectively. Conclusion: This is the first study describing sensitivities for microbial keratitis in Durban, South Africa. Similar results have been published in Johannesburg. The current treatment protocol at the UKZN Department of Ophthalmology for corneal ulcers is appropriate.
Aphakic iris-claw (Artisan®/Verisyse) lens implantation in low-income African population.
(2007) Kruse, Carl-Heinz.; Linda, Visser.
Purpose: To test the viability of implanting the Artisan®/VerisyseTM lens in a low-income monocular aphakic African population with insufficient capsular support where contact lens wear is expensive and spectacle correction is not possible, by assessing the postoperative visual functions. To further assess whether adverse effects (e.g.: pigment dispersion with secondary glaucoma, prolonged uveitis) in patients with highly pigmented irises would be as low as with patients in European and American trials. Methods: A prospective, randomised, controlled clinical trial comparing outcomes in two groups of unilateral aphakic patients. The patients in the first group received an Artisan intra-ocular iris-claw lens as a secondary procedure while the second group remained aphakic (the current treatment status quo for public patients in KwaZulu-Natal province in South Africa). Follow-up was done for 1 year. Results: The study was terminated early due to ethical and statistical reasons. Nine treated and five control patients were included. Monocular uncorrected vision was significantly higher in the treatment group (P=0,012) and patient satisfaction was higher (p=0,002). Changes in other variables (intraocular pressure, angle pigmentation, change in cup-to-disc ratio, iris pigment changes and best spectacle corrected vision) were not significantly different between the two groups. Conclusion: The Artisan®/VerisyseTM lens is a feasible option for aphakic African patients with regard to visual outcome, safety and patient satisfaction. This form of refractive correction should be the standard for patients with no capsular support and where other options are too expensive or carry greater risk.
Intravitreal versus sub-tenon triamcinolone acetonide for refactory diffuse diabetic macular oedema.
(2008) Zaborowski, Anthony Grant.; Visser, Linda.
Purpose: To compare the safety and efficacy of intravitreal (IVT) and sub-Tenon (ST) triamcinolone acetonide for the treatment of refractory diffuse diabetic macular oedema. Method: 29 eyes of 22 patients with long-standing, diffuse diabetic macular oedema refractory to argon laser treatment were randomly assigned to a single 4mg injection of IVT triamcinolone acetonide or a 40mg sub-Tenon injection. Patients were subsequently monitored for six to nine months. Outcome measures were visual acuity, intraocular pressure, macular thickness on optical coherence tomography and adverse effects. Results: There was no significant improvement in visual acuity in either group. A transient decrease in macular thickness was found in the IVT group but not in the ST group. There were no significant adverse effects apart from a mild to moderate intra-ocular pressure rise found more frequently in the IVT group. Conclusion: IVT and ST triamcinolone acetonide injections for refractory diffuse diabetic macular oedema appear relatively safe and well-tolerated. IVT injection produces a significant temporary decrease in macular thickness in patients with long-standing diffuse diabetic macular oedema while ST injection does not. Neither intervention was shown to significantly improve visual acuity in this group of patients.

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