|Year : 2013 | Volume
| Issue : 1 | Page : 23-28
Challenges in the management of glaucoma in university of Calabar teaching hospital, Calabar, Nigeria: A 10 year review
Uduak E Asana1, Emmanuel O Megbelayin2, Affiong A Ibanga1, Dennis G Nkanga1, Roseline E Duke1, Bassey A Etim1
1 Department of Ophthalmology, University of Calabar Teaching Hospital, Calabar, Nigeria
2 Department of Ophthalmology, University of Uyo Teaching Hospital, Uyo, Nigeria
|Date of Web Publication||28-Aug-2013|
Emmanuel O Megbelayin
Department of Ophthalmology, University of Uyo Teaching Hospital, Uyo, Akwa-Ibom State
Source of Support: None, Conflict of Interest: None
Background: Glaucoma is a common cause of blindness in developing nations. The objective of this study is to determine the severity of primary open angle glaucoma and audit health records of glaucoma patients in our center.
Materials and Methods: A retrospective case note search of glaucoma patients from out-patient clinic was carried out between January 2001 and December 2010. Data analysis included descriptive statistics and exact binomial 95% confidence interval (CI) calculated for the mean estimates.
Results: Seventy-six patients (152 eyes), comprising 49 (64.5%) males and 27 (35.5%) females were included in the study. The age ranged from 15 to 88 years (mean: 54.2 ± 14.5). Forty-five (59.7%) presented with normal vision and 10 (13.2%) had visual acuity <3/60 in at least one eye. Cup-Disc-Ratio (CDR) on the right eyes were ≤0.6 = 12 (15.8%), >0.6 < 0.9 = 27 (35.5%), >0.9 = 35 (46.1%) and left eyes were 15 (19.7%), 29 (38.2%), 28 (36.8%), respectively. Mean intraocular pressure (right eyes) at presentation was 20.3 mmHg (95% CI, 17.4-23.3) and reduced to 13.4 mmHg (95% CI, 10.7-16.0) at the last readings while left eyes from a mean of 20.3 mmHg (95% CI, 16.9-23.8) reduced to 12.1 mmHg (95% CI, 10.0-14.3). The mean presenting CDR were 0.79 (95% CI, 0.74-0.83) and 0.73 (95% CI, 0.68-0.79) in right and left eyes, respectively. CDR showed statistical significance with age (p < 0.001, yate-corrected X 2 -test) but not with sex (p = 0.807).
Conclusion: Late presentation of glaucoma cases is a major problem in Calabar. We recommend public enlightenment, case detection, and early treatment to reduce ocular morbidity.
Keywords: Glaucomatous optic atrophy, health records, late presentation
|How to cite this article:|
Asana UE, Megbelayin EO, Ibanga AA, Nkanga DG, Duke RE, Etim BA. Challenges in the management of glaucoma in university of Calabar teaching hospital, Calabar, Nigeria: A 10 year review. Arch Int Surg 2013;3:23-8
|How to cite this URL:|
Asana UE, Megbelayin EO, Ibanga AA, Nkanga DG, Duke RE, Etim BA. Challenges in the management of glaucoma in university of Calabar teaching hospital, Calabar, Nigeria: A 10 year review. Arch Int Surg [serial online] 2013 [cited 2020 Jun 4];3:23-8. Available from: http://www.archintsurg.org/text.asp?2013/3/1/23/117140
| Introduction|| |
Glaucoma is a group of disease which has in common characteristic optic neuropathy and optic disc changes in which intraocular pressure (IOP) is a major and the only modifiable factor.  The Baltimore Eye Survey and the Barbados study suggest glaucoma is prevalent in blacks.  The prevalence of blindness in Nigeria is 1% with glaucoma accounting for 17.1% of bilateral blindness. ,, Nigeria is a country in West Africa with a population of about 160 million and life expectancy at birth for males and females of 46.5 and 48.1 years, respectively.  Age, being an important risk factor for primary open angle glaucoma (POAG), and with the projected increase in life expectancy of some developing nations, including Nigeria, it is expected that POAG will pose an increasing burden on eye care services. 
Well-preserved clinical information from glaucoma patients is yet to be closely looked into as an avenue for improved patient care. There is paucity of literature on impact of health records on glaucoma management. Yet feedbacks are expected from various glaucoma treatment protocols. In this study we conducted comprehensive case file audits of our glaucoma patients over a 10-year period. We specifically sought to investigate severity of glaucoma and our health record profile.
| Materials and Methods|| |
It was a retrospective study. All cases included in the study had visual acuity (VA) with a standard Snellen's chart at 6 m. Fundoscopy was performed with Keeler (Keeler Ltd, Windsor, UK), Welch-Allyn (Welch-Allyn Inc., New York, USA) or Heine (Heine instruments Ltd, Ontario, Canada) ophthalmoscopes depending on the attending ophthalmologist. 78 D Volk lens (Volk Optical Inc. Ohio, USA) along with slit lamp (Zeiss) was used for stereoscopic views of the cupped discs. Gonioscopy was carried out by Goldmann three-mirror contact lens (Volk Optical Inc. Ohio, USA) either at presentation or subsequently. IOP was recorded by either Goldmann applanation tonometer (Haag-Streit, Bern, Switzerland) mounted on a slit lamp (Zeiss) or Perkins applanation tonometer (Clement-Clarke Inc., Columbus, Ohio, USA). Threshold perimetry was obtained with Synemed EP-910 automated visual field analyzer (Synemed Inc., California, USA).
Medical records of glaucoma patients seen in the eye clinic from 2 nd January, 2001 to 31 st December, 2010 were reviewed. Information on age, sex, presenting complaints, visual field defects, and IOP was recorded on a special proforma designed to meet study's objectives. The diagnosis of glaucoma was either made or confirmed by a consultant ophthalmologist. Procedures of data collection were as outlined in Helsinki declaration.
The diagnosis of POAG was made based on the presence of two of the following. ,
Severity of glaucoma was graded using the modified grading system proposed by Jay as follows. 
- Disc atrophy (glaucomatous type) with at least Cup-Disc-Ratio (CDR) of 0.5 or disc atrophy of ≥0.2 asymmetry
- Elevated IOP of >21 mmHg. Pachymetry, which could have correlated corneal thickness with applanation tonometry, was not done in the years under review because of unavailability. However, many population and clinic-based glaucoma studies have reported on IOPs without pachymetry. ,,,,,
- Characteristic visual-field defects such as abnormal glaucoma hemi-field test, paracentral or arcuate scotomas, nasal steps, central or temporal islands. Others are ≥2 contiguous points on the pattern standard deviation plot with p < 0.01 loss or ≥3 contiguous points with p < 0.05 loss or greater, or a 10 dB difference across the nasal horizontal midline at ≥2 adjacent points in the total deviation plot. To be reliable, a visual field test must have fixation losses, false positive and false negative <25%.
Trabeculectomy with 5-fluorouracil is the standard method of surgical treatment offered to our patients. However, majority of patients often opt for topical ocular hypotensives because of fear and perceived doubtful outcome of filtering surgery. Patients on medical management are given between 1 and 3 months for routine clinic visits depending on glaucoma severity and degree of IOP control.
- Stage 1, suspicious shape of the optic cup but cup/disc ratio less than or equal to 0.6
- stage 2, pathological cup/disc ratio greater than 0.6 but less than 0.9
- and stage 3, end-stage cupping with cup/disc ratio greater than or equal to 0.9.
Patients with ocular hypertension (i.e., with no glaucomatous damage but raised IOP > 21 mmHg), glaucoma suspect (those who had only one of the criteria above) were excluded from this study. Those with occludable angles, secondary glaucoma, and other co-morbidities such as cataract, age-related macular degeneration, and history of previous trauma or intraocular surgery, except following uncomplicated cataract were also excluded.
Statistical analysis was performed with the SPSS (SPSS for Windows, Rel 15.0; 2008. SPSS Inc, Chicago, IL, USA) software. Descriptive statistics using frequencies and proportions were summarized. Data was normally distributed; means ±95% confidence interval (CI) (or standard deviation) were reported. p values < 0.05 were considered statistically significant.
| Results|| |
In the period under study, 1,794 patients diagnosed with POAG were identified from the clinic register to retrieve patients' case files from the health records department. Only 512 (28.5%) could be retrieved out of which 76 (4.2%) met the stringent inclusion criteria for the study's definition of POAG. Three hundred and fifteen (17.6%) had missing information with regards to study's inclusion criteria, 34 (1.9%) with non-glaucomatous optic atrophy, 38 (2.1%) with ocular hypertension or glaucoma suspect and 49 (2.7%) with secondary or pediatric glaucoma. Of the 79 patients with POAG, 49 (64.5%) and 27 (35.5%) were males and females, respectively (M:F = 1:0.6). The age ranged from 15 to 88 years with a mean of 54.2 + 14.5 [Table 1]. Some of the identified reasons for few cases included missing case files, loss of parts of patients' documentation, and scanty ophthalmic examination that left out study's criteria for diagnosing POAG. During this period, the Ophthalmology department was moved to the permanent site with the rest of the hospital. This partly could explain the loss of case files in transit. Again, patients' records were in loose sheets, making such sheets liable to get missing.
All the patients were blacks, 36 (47.4%) of whom were civil servants. Only 16 (21.1%) were pensioners [Table 2]. Majority, 53 (67.3%), presented to the eye clinic on account of painless progressive blurring of vision. Only 2 (2.6%) came for routine eye check-up [Figure 1]. Forty-five patients (59.7%) presented with normal vision in both eyes and 10% were blind in both eyes [Table 3].
IOP and CDR findings are as shown in [Figure 2] and [Figure 3]. Presenting IOP on the right eye reduced from a mean of 20.3 mmHg (95% CI, 17.4-23.3) to 13.4 mmHg (95% CI, 10.7-16.0) at the last readings. IOP in the left eye reduced from a mean of 20.3 mmHg (95% CI, 16.9-23.8) to 12.1 mmHg (95% CI, 10.0-14.3) at the last readings. The mean presenting CDRs were 0.79 (95% CI, 0.74-0.83) and 0.73 (95% CI, 0.68-0.79) in right and left eye, respectively. CDR showed statistical significance with age (p < 0.0001) but not with sex (p = 0.807) while IOP showed no statistical significance with neither age (p = 0.115) nor sex (p = 0.502).
Lack of cooperation, distorting corneal pathology, central corneal leukomas and dense nuclear sclerosis prevented CDR and IOP determination in some eyes.
| Discussion|| |
Age was found to be associated with glaucomatous cupping in this study. This is similar to several population and clinic-based studies on glaucoma. ,,,, Age above 40 years is generally known to be a risk factor for POAG. There appears to be inconsistencies in the literature on the association of gender and POAG. The current study, like similar studies on glaucoma, ,,, did not find association between sex and glaucomatous optic atrophy. However, in a meta-analysis by Alicja et al.,  after adjusting for age, race, year of publication, and survey methods, men were 1.37 (95% CI, 1.22-1.53) times more likely than women to have POAG. This meta-analysis excluded indigenous Africans and could partly explain the reported association.
At its very early stage the diagnosis of glaucoma is not only difficult but also requires sophisticated resources. This is often a challenge for screening for glaucoma especially in resource-limited economy. The limitation notwithstanding, if patients present early enough, there are ocular clinical features that can arouse suspicion of glaucoma once they are found during eye examination. However, late presentation, common in developing countries, is a major problem in the management of patients with POAG. ,,,
The mean presenting CDR in this study was 0.79. This parallels similar findings within and outside Nigeria. In Kano, North Western Nigeria, 63% of patients had CDR of more than 0.8 in their good eye at presentation.  Also, in Azare, North Eastern Nigeria, Olatunji et al.,  reported CDR of 0.2-0.5 in (5.7%) and 0.6-0.7 in (9.6%) and 0.8 or greater in (84.7%). In a retrospective analysis of case records of 163 glaucoma patients, Bowman et al.,  in East Africa reported CDR of 0.8 or worse in 131 (85%) patients. Ellong et al.,  reported a mean CDR of 0.7 (±0.2) in neighboring Cameroon.
In the current study, majority (67.3%) of the patients presented on account of subjective visual loss in one or both eyes. This is comparable with the 77.3% reported by Omoti et al. in a clinic-based study in Benin-city, Nigeria.  Early detection of glaucoma is the key factor in preserving good eye sight. Glaucoma affects central vision in the very late stages of the disease. Waiting for deteriorating vision before presenting to a health facility is often a reason for late presentation.
More than 10% of our patients were bilaterally blind at presentation. This was lower than other Nigerian figures of 17.7% and 24% reported by Enock et al.,  and Omoti et al.,  respectively. This difference could be attributable to different geographical locations, inconsistencies in the definition of POAG among the different studies and methodology. For instance, the study by Omoti et al.,  was a prospective study in which ophthalmologic parameters were more deliberately selected and thoroughly monitored throughout the course of the study. Olatunji et al.  reported that as much as 42% of glaucoma patients were blind at presentation. This could be because the study included other types of glaucoma and the location, Northern Nigeria, has the poorest health indices in the country.
Across Africa, similar to the findings in this study, it can be said that patients present at advance stages of glaucoma with attendant ocular morbidity. In a retrospective case series of 449 patients (891 eyes) in North Eastern Ghana, Gyasi et al.,  reported that 34.1% of patients were bilaterally blind while 50% were uniocularly blind with 70.2% and 54.9% having CDRs of >0.8 and 1.0, respectively at presentation. Rotchford et al.,  in a South African survey reported that 58% were blind in at least one eye at presentation. This trend was also recorded by Mafwiri et al.,  in Tanzania where at presentation, 87 (30%) had visual impairment, 86 (29%) were blind and 70% had CDR greater than 0.8 in the better eye. Reasons alluded to late presentation range from socio-economic deprivation, low literacy to challenges with glaucoma service delivery. ,, Other reasons why people needlessly go blind from glaucoma include socio-cultural beliefs, inaccessible eye care facilities, non-compliance to prescribed ocular hypotensives and the diagnostic and therapeutic difficulties inherent in the disease. ,,,
There is need for vision screening and regular check-ups in African settings especially among those with family history of glaucoma and adults above 40 years. In an African summit, the World Glaucoma Association has advocated opportunistic glaucoma screening that ensures screening and treatment of identified cases at every opportunity a trained eye worker encounters at-risk individuals.  Visions screening should include health talks that enlighten patients on the role and efficacy of surgical intervention in the management of glaucoma. The scarcity of ophthalmologists in our environment demands that health workers, including optometrists, ophthalmic nurses, and primary health workers be trained to screen for glaucoma at primary and secondary levels before referral to ophthalmologists, who often are in tertiary centers. To obviate omission of vital clinical information, a standardized glaucoma protocol is suggested. The use of electronic record system is also recommended for up-to-date records. Such electronic records should have backups outside the base hospital in the events of damages or disasters.
The following limitations of this study have been identified. First, the few subjects analyzed as a result of defective health record system limit generalizability of our reports. Second, determination of corneal thickness may have validated the reported IOPs. Although many studies on glaucoma have reported IOPs without pachymetry, thus, allowing for reasonable comparison with the current study. ,,,,, Third, the study is retrospective, but we believe it will contribute valuable information regarding a cost-effective means of reducing blindness from glaucoma, especially in developing countries. A prospective randomized clinical trial that seeks deeper understanding of the behavioral factors determining the timing of presentation of glaucoma patients and uptake of glaucoma surgical services in our peculiar African environment is desirable.
| Conclusion|| |
Most of our glaucoma patients came at blinding stages of the disease. To tackle the growing problem of glaucoma, especially in developing nations, improving glaucoma awareness, case detection, counseling, efficient referral system, and early treatment is advocated.
| Acknowledgment|| |
Health Records Department, University of Calabar Teaching Hospital, Calabar, Nigeria.
| References|| |
|1.||Saarela V, Falck A, Airaksinen PJ, Tuulonen A. The sensitivity and specificity of Heidelberg Retina Tomograph parameters to glaucomatous progression in disc photographs. Br J Ophthalmol 2010;94:68-73. |
|2.||Leske MC, Connell AM, Schachat AP, Hyman L. The Barbados Eye Study. Prevalence of open angle glaucoma. Arch Ophthalmol 1994;112:821-9. |
|3.||World Health Organization. Available data on blindness. WHO/PBL/2010. pp. 1-5. |
|4.||Nwosu SN. Blindness and visual impairment in Anambra State, Nigeria. Trop Geogr Med 1994;46:346-9. |
|5.||Ajibode HA. The prevalence of blindness and visual impairment in Ikenne Local Government Area of Ogun State, Nigeria. Nig J Ophthalmol 1999;7:23-7. |
|6.||World Health Rankings. Available from: http://www.worldlifeexpectancy.com/country-health-profile/nigeria. [Last accessed 2012 october 24]. |
|7.||Ntim-Amponsah CT, Amoaku WM, Ofosu-Amaah S, Ewusi RK, Idirisuriya-Khair R, Nyatepe-Coo E, et al. Prevalence of glaucoma in an African population. Eye (Lond) 2004;18:491-7. |
|8.||Ng WS, Agarwal PK, Sidiki S, McKay L, Townend J, Azuara-Blanco A. The effect of socio-economic deprivation on severity of glaucoma at presentation. Br J Ophthalmol 2010;94:85-7. |
|9.||Foster PJ, Buhrmann R, Quigley HA, Johnson GJ. The definition and classification of glaucoma in prevalence surveys. Br J Ophthalmol 2002;86:238-42. |
|10.||Anand N, Mielke C, Dawda VK. Trabulectomy outcomes in advanced glaucoma in Nigeria. Eye (Lond) 2001;15:274-8. |
|11.||Verrey JD, Foster A, Wormald R, Akuamoa C. Chronic glaucoma in northern Ghana - A retrospective study of 397 patients. Eye (Lond) 1990;4:115-20. |
|12.||Quigley HA, Buhrmann RR, West SK, Isseme I, Scudder M, Oliva MS. Long term results of glaucoma surgery among participants in an east African population survey. Br J Ophthalmol 2000;84:860-4. |
|13.||Lachkar Y, Leyland M, Bloom P, Migdal C. Trabeculectomy with intraoperative sponge 5-fluorouracil in Afro-Caribbeans. Br J Ophthalmol 1997;81:555-8. |
|14.||Kiage DO, Gradin D, Gichuhi S, Damji KF. Ahmed glaucoma valve implant: Experience in East Africa. Middle East Afr J Ophthalmol 2009;16:151-5. |
|15.||Enock ME, Omoti AE, Momoh RO. Glaucoma in a sub-urban tertiary care Hospital in Nigeria. J Ophthalmic Vis Res 2010;5:87-91. |
|16.||Jay JL. Earlier trabeculectomy. Trans Ophthal Soc UK 1983;103:35-8. |
|17.||Buys YM, Harasymowycz P, Gaspo R, Kwok K, Hutnik CM, Blondeau P, et al. Comparison of newly diagnosed ocular hypertension and open-angle glaucoma: Ocular variables, risk factors, and disease severity. J Ophthalmol. 2012, article:, DOI: 10.1155/2012/757106 2012. |
|18.||Khandekar R, Jaffer MA, Al Raisi A, Zutshi R, Mahabaleshwar M, Shah R, et al. Oman Eye Study 2005: Prevalence and determinants of glaucoma. East Mediterr Health J 2008;14:1349-59. |
|19.||Ramakrishnan R, Nirmalan PK, Krishnadas R, Thulasiraj RD, Tielsch JM, Katz J, et al. Glaucoma in a rural population of southern India: The Aravind comprehensive eye survey. Ophthalmology 2003;110:1484-90. |
|20.||Vijaya L, George R, Paul PG, Baskaran M, Arvind H, Raju P, et al. Prevalence of open-angle glaucoma in a rural south Indian population. Invest Ophthalmol Vis Sci 2005;46:4461-7. |
|21.||Quigley HA. Number of people with glaucoma worldwide. Br J Ophthalmol 1996;80:389-93. |
|22.||Tielsch JM, Sommer A, Katz J, Royall RM, Quigley HA, Javitt J. Racial variations in the prevalence of primary open-angle glaucoma. The Baltimore Eye Survey. JAMA 1991;266:369-74. |
|23.||Johnson GJ. In: Minassian DC, Weale R, editors. The Epidemiology of Eye Disease. London. Chapman & Hall Medical, Lippincott-Raven Publishers; 1998. pp. 76. |
|24.||Rudnicka AR, Mt-Isa S, Owen CG, Cook DG, Ashby D. Variations in primary open-angle glaucoma prevalence by age, gender, and race: A Bayesian meta-analysis. Invest Ophthalmol Vis Sci 2006;47:4254-61. |
|25.||Thomas R, Parikh RS. How to assess a patient for glaucoma. Community Eye Health 2006;19:36-7. |
|26.||Ayansiji Ayanniyi A, Olasunkanmi Olatunji F, Olarongbe Mahmoud A, Oluwafunke Ayanniyi R. Clinical findings among nigerian paediatric glaucoma suspects during a school eye health survey. Open Ophthalmol J 2008;2:137-40. |
|27.||Egbert PR. Glaucoma in West Africa: A neglected problem. Br J Ophthalmol 2002;86:131-2. |
|28.||Bowman RJ, Kirupananthan S. How to manage a patient with glaucoma in Africa. J Comm Eye Health 2006;19:38-9. |
|29.||Olatunji FO, Ibrahim UF, Muhammad N, Msheliza AA, Ibrahim UY, Rano BT, et al. Challenges of glaucoma service delivery in Federal Medical Centre, Azare, Nigeria. Afr J Med Med Sci 2008;37:355-9. |
|30.||Bowman RJ, Hay A, Wood ML, Murdoch IE. Combined cataract and trabeculectomy surgery for advanced glaucoma in East Africa; visual and intra-ocular pressure outcomes. Eye (Lond) 2010;24:573-7. |
|31.||Ellong A, Mvogo CE, Bella-Hiag AL, Mouney EN, Ngosso A, Litumbe CN. Prevalence of glaucomas in a Black Cameroonian population. Sante 2006;16:83-8. |
|32.||Omoti AE, Osahon AI, Waziri-Erameh MJ. Pattern of presentation of primary open-angle glaucoma in Benin City, Nigeria. Trop Doct 2006;36:97-100. |
|33.||Olatunji FO, Ibrahim UF, Muhammad N, Msheliza AA, Akku BE, Ibrahim UY. et al The types and treatment of glaucoma among adults in North Eastern part of Nigeria. Tanzania Med J 2009;24:24-7. |
|34.||Gyasi M, Amoako W, Adjuik M. Presentation patterns of primary open angle glaucomas in north eastern ghana. Ghana Med J 2010;44:25-30. |
|35.||Rotchford AP, Kirwan JF, Muller MA, Johnson GJ, Roux P. Temba glaucoma study: A population-based cross-sectional survey in urban South Africa. Ophthalmology 2003;110:376-82. |
|36.||Mafwiri M, Bowman RJ, Wood M, Kabiru J. Primary open-angle glaucoma presentation at a tertiary unit in Africa: Intraocular pressure levels and visual status. Ophthalmic Epidemiol 2005;12:299-302. |
|37.||Muir KW, Santiago-Turla C, Stinnett SS, Herndon LW, Allingham RR, Challa P, et al. Health literacy and adherence to glaucoma therapy. Am J Ophthalmol 2006;142:223-6. |
|38.||Thomas R, Korah S, Padma P. Glaucoma an emerging cause for preventable blindness. Indian J Commun Health 1997;3:52-63. |
[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2], [Table 3]