Glaucoma Treatment Patterns in Sub-Saharan Africa.

PRCIS: Physicians were most likely to recommend primary medical therapy upon diagnosis of glaucoma. Laser therapy was underutilized where they were available. Physicians were more likely to recommend surgery in severe glaucoma, laser therapy in mild glaucoma, while recommendation of medical therapy did not depend on glaucoma severity. PURPOSE: To characterize treatment patterns for newly diagnosed glaucoma in sub-Saharan Africa (SSA). METHODS: This was a multicenter cross-sectional study of adults newly diagnosed with glaucoma at 27 eye care centers in 10 African countries. In addition to demographic and clinical data, physician treatment recommendations (medication, laser, surgery, or no treatment) were recorded. Statistical analyses were performed using STATA version 14.0. RESULTS: Data from 1201 patients were analyzed. Physicians were most likely to recommend primary medical therapy upon diagnosis of glaucoma (69.4%), with laser (13.2%), surgery (14.9%), and no treatment (2.5%) recommended to the remaining patients. All sites had medical therapy available and most (25/27, 92.6%) could provide surgical treatment; only 16/27 (59.3%) sites offered laser, and at these sites, 30.8% of eyes were recommended to undergo primary laser procedures. As glaucoma severity increased, the laser was recommended less, surgery more, and medications unchanged. Patient acceptance of medical therapy was 99.1%, laser 88.3%, and surgery 69.3%. CONCLUSIONS: Medical therapy for first-line glaucoma management is preferred by most physicians in SSA (69%). Laser therapy may be underutilized at centers where it is available. These findings underscore the need for comparative studies of glaucoma treatments in SSA to inform the development of evidence-based treatment guidelines and of programs to reduce glaucoma blindness in SSA. Strategic approaches to glaucoma therapy in SSA must address the question of whether medical therapy is the most optimal first-line approach in this setting.

Comparison of Ocular Biomery in Primary Open Angle Glaucoma and Non-glaucoma in South West Nigeria.

Background: Glaucoma is a public health problem in Nigeria. The number of individuals affected by glaucoma in Nigeria is much higher than the individuals known to have the disease. Ocular parameters such as intraocular pressure, central cornea thickness, axial length and refractive error have all been documented as risk factors of glaucoma especially among Caucasians and African Americans, with little documentation in Africa where there's an alarming rate of blindness. Aim and Objectives: To compare central cornea thickness (CCT), intraocular pressure (IOP), axial length (AL) and refractive state in participants with primary open angle glaucoma (POAG) and non-glaucoma in South-West Nigeria. Materials and Methods: This hospital-based case-control study was carried out among 184 newly diagnosed POAG and non-glaucoma adult participants attending the outpatient clinic of Eleta eye institute. The CCT, IOP, AL and refractive state were measured in each participant. Test of significance between proportions in categorical variables were assessed using chi square test (χ2) in both groups. The means were compared using independent t-test while correlation between parameters were analyzed using Pearson correlation coefficient. Results: The mean age of the POAG participants was 57.16 + 13.3 years and the mean age of the non-glaucoma participants was 54.15 + 13.4 years. The mean IOP in the POAG group was 30.2 + 8.9mmHg while non- glaucoma group was 14.2 + 2.6mmHg (P < 0.001), other ocular parameters were not significantly different in both groups. In the POAG group, decreased spherical equivalent refractive error (i.e increasing myopia) was significantly associated with increased axial length (r= -0.252, P = 0.01), but not significant in the non- glaucoma group. However, in the non-glaucoma group, central cornea thickness increased with increasing intraocular pressure (r= 0.305, P = 0.003), which was not significant in the glaucoma group. Conclusion: Patients with POAG had much higher IOP and thus, IOP remains a significant risk factor in its development. There was a significant relationship between refractive state and axial length in the POAG group while a significant relationship was identified between central cornea thickness and intraocular pressure in the non- glaucoma group.

Amsler Grid Versus 10-2 Test in Primary Open Angle Glaucoma.

Background: Glaucoma is the leading cause of global irreversible blindness. The goal of management in glaucoma lies in its early detection and treatment to prevent further optic neuropathy. Available equipment for early glaucoma detection is not cost-effective or readily available in resource-scarce settings such as Nigeria. Thus, there is a need for a simple cost-effective tool to detect glaucomatous central visual field (CVF) defects in all the stages of glaucoma within the community in resource scarce-settings. Aims and Objectives: The aim of this article is to determine the validity of the Amsler grid in detecting central glaucomatous visual field defects in primary open angle glaucoma (POAG). Materials and Methods: This was a cross-sectional study of follow-up glaucoma patients at a secondary eye care hospital in Nigeria. All patients had detailed ophthalmic examination in addition to 24-2 and 10-2 CVF tests and Amsler grid test. POAG was classified using the Hodapp-Parrish-Anderson criteria into mild, moderate, and severe on 24-2 CVF. The diagnostic validity of the Amsler grid was calculated using the 10-2 CVF as a reference standard. Regression analyses were performed between the Amsler grid scotoma area and 10-2 CVF parameters [mean deviation (MD), scotoma extent (SE), and scotoma mean depth (SMD)]. Results: A total of 150 eyes of 150 patients were enrolled. The sensitivity, specificity, and positive predictive value and negative predictive value of the Amsler grid compared with the 10-2 CVF was 49.5%, 95.9%, 96.2%, and 47.9%, respectively, with an area under curve of 0.7. Sensitivity increased with increasing severity (P < 0.001) from 20.0%, 31.0%, and 76.6% in mild, moderate, and severe POAG, respectively. The Amsler grid scotoma area had the strongest relationship with the 10-2 MD, followed by 10-2 SE and 10-2 SMD with a quadratic R2 of 0.579, 0.370, and 0.307, respectively. Conclusion: The Amsler grid has a low sensitivity in mild-to-moderate POAG. However, it may serve as an adjunctive tool in resource-scarce settings for detection of severe POAG in the community by primary eye care providers.

The social construction of genomics and genetic analysis in ocular diseases in Ibadan, South-western Nigeria.

Genomics, an emerging field to improve public health practice, has potential benefits to understanding ocular diseases. This study explored the social construction of genomics in ocular diseases in the blind community in Ibadan, Nigeria, through two focus group discussions and twelve in-depth interview sessions conducted among people living with ocular disorders. The data were thematic and content-analysed. Although the participants had limited knowledge about ocular diseases, genomics, and their nexus, they maintained a positive attitude toward its potential benefits. This informed their willingness to participate in genomics testing for ocular diseases. The participants preferred saliva-based sample collection over blood-based, and expressed concern for the procedure and accrued benefits of genomics studies. Thus, public sensitisation about ocular diseases and client-centred genomics testing procedures should be engendered.

Clinical Characteristics and Stage at Presentation of Glaucoma Patients in Sub-Saharan Africa.

PRCIS: The initial presentation of glaucoma varies meaningfully across SSA. A comprehensive strategy with regional customization based on local differences is needed to reduce glaucoma blindness in SSA. PURPOSE: To explore regional variations in the presentation of newly diagnosed glaucoma in Sub Saharan Africa (SSA). METHODOLOGY: This was a multicenter, cross-sectional study in which newly diagnosed, consecutive, glaucoma patients aged older than or equal to 18 years were recruited from 27 eye clinics in 10 countries throughout SSA. Demographic and ophthalmic examination data were collected. Glaucoma severity was based on optic nerve head and visual field assessment. Statistical analyses were performed using STATA version 14.0. RESULTS: Among 1214 enrolled patients with newly diagnosed glaucoma from Western, Eastern, and Southern Africa, the overall mean (SD) age was 59.9 (17.1) years. More than half of all patients (716/1178; 60.8%) presented with severe glaucoma in the worse eye, and one-third (36.9%) had severe glaucoma in both eyes. Primary open angle glaucoma was the commonest form of glaucoma in all regions (77.4%). A family history of blindness (260/1204, 21.6%) was common. Patients from Western Africa had lower mean presenting intraocular pressure (26.4 [11.1] mm Hg, P <0.001), but had worse glaucoma in the better eye based on mean cup-disc ratio (0.8; P <0.001) and mean visual field mean deviation [10.4 (8.4)] dB, P =0.016) compared with other regions. Exfoliation glaucoma was more common in Eastern Africa (30/170=17.7%, P <0.001) compared with other regions. CONCLUSION: The initial presentation of glaucoma varies meaningfully across SSA. A comprehensive strategy with regional customization based on local differences is needed to reduce glaucoma blindness in SSA.

The Effect of Direct Health Education on the Uptake of Screening by First Degree Relatives of Glaucoma Patients in Nigeria.

PRCIS: First degree relatives (FDRs) of glaucoma patients are more likely to present for screening when they are directly contacted and educated by health workers on the phone compared with when they are only invited by their relative with glaucoma. OBJECTIVE: The aim was to determine the effect of direct health education by phone calls on the uptake of glaucoma screening among FDRs of primary open angle glaucoma patients as a glaucoma blindness control strategy in an asymptomatic high-risk African population. METHODS: This was a randomized clinical trial in which 102 primary open angle glaucoma patients (probands) were randomized into control and intervention groups. Both proband groups were educated about glaucoma and requested by the investigator to invite their adult FDR to attend a screening clinic within 1 month. In addition, the FDRs in the intervention group were directly contacted, educated, and invited for examination by phone calls. A total of 560 FDRs were enumerated by the probands. The main outcome measure was proportion of FDR that presented for screening. RESULTS: A total of 218 (38.9%) FDRs took up glaucoma screening services. Eighty-nine (30.1%) of the 296 FDRs in the control group and 129 (48.9%) of the 264 FDRs in the intervention group presented for examination. After multivariate analysis, FDRs in the phone call group were 2.506 times [95% confidence interval (CI): 1.695-3.706] more likely to present than FDRs in the no phone call group. Young FDRs were more likely to present [odds ratio (OR)=3.593; 95% CI: 1.613-8.007] than the elderly FDRs, while FDRs living within 200 km of the hospital were also more likely to present (OR=5.200; 95% CI: 2.860-9.456) than those living far (>200 km) away. Probands with moderate to severe visual impairment were significantly more likely (OR=3.073; 95% CI: 1.845-4.352) to have their FDRs present than probands with mild or no visual impairment. CONCLUSION: Direct contact and health education of FDRs through phone calls had a significant positive effect on the uptake of glaucoma screening by FDRs. We recommend direct contact and education of the FDRs of glaucoma patients.

Surgical outcomes of membrane-tube-type glaucoma shunt device in indigenous West Africans.

PURPOSE: The aim of this study was to report the safety and efficacy of the membrane-tube (MT)-type glaucoma shunt device (Finetube MT) in the management of refractory glaucoma in indigenous West Africans. METHODS: The Finetube MT was implanted into 25 eyes of 25 West African patients with refractory glaucoma. These patients had inadequate intraocular pressure (IOP) control despite maximum tolerable IOP-lowering medications with or without previous ocular surgeries. IOP, postoperative complications, interventions, visual acuities, and the number of IOP-lowering medications were analyzed preoperatively and postoperatively. RESULTS: The mean (standard deviation [SD]) age of the patients was 49.7 (20.9) years. The mean (SD) follow-up duration was 21.0 (10.6) months. Postoperatively, the mean (SD) IOP reduced from a preoperative value of 38.1 (10.3) mmHg to 14.5 (4.6), 16.1 (7.8), and 14.7 (3.0) mmHg at 1, 2, and 3 years postoperatively, respectively, representing 61.9%, 57.7%, and 61.4% reduction from baseline (P<0.01). The mean (SD) number of IOP-lowering medications reduced from 4.1 (1.0) to 0.6 (0.9) at 1 year and 0.9 (1.1) at 2 years after the operation (P<0.01). Using an IOP level between 6 and 21 mmHg and reduced by ≥20% from baseline, the cumulative survival rate (standard error) was 96.0% (3.9%) at 6 months, 89.0% (6.0%) at 18 months, and 81.3% (10.6%) at 3 years after the operation. There was no postoperative ocular hypotony, tube occlusion, or device exposure. CONCLUSION: The Finetube MT may effectively control IOP with minimal risk of postoperative complications in indigenous West Africans.

Experience with argon laser trabeculoplasty in Nigerians.

AIM: To report the safety and efficacy of Argon Laser Trabeculoplasty (ALT) in reducing intraocular pressure (IOP). SETTINGS AND DESIGN: This was a retrospective study performed on 25 eyes of 25 patients. METHODS AND MATERIALS: Consecutive patients who met the inclusion criteria for ALT were recruited from the ophthalmic clinic of the University College Hospital Ibadan, Nigeria and followed up for a minimum period of six months. Two criteria were used to define successful response. Criterion 1 was defined as IOP reduction of 3mmHg or more without additional intervention while criterion 2 was IOP reduction of 20% or more from the pretreatment IOP. STATISTICAL ANALYSIS: Data was analyzed using SPSS version 16. Frequencies and means were generated to observe patterns of variable distribution among the patients. P value < 0.05 was considered significant. RESULTS: The mean pretreatment IOP was 19.9 ±3.1mmHg, (range of 16 to 26 mmHg). Mean post treatment IOP at 6 months was 14.9 ±2.2 mmHg, (range of 11 to 19 mmHg). Mean IOP reduction at one year was 4.6 mmHg, representing a 22.3% drop. There was a statistically significant greater IOP reduction in eyes (P<0.001) with higher pretreatment IOP. Based on criterion 1 and 2, 84.0% of the patients had successful outcome at six months while at one year, 76.9% were successful based on criterion one. CONCLUSION: To the best of our knowledge, this is the first study to report the efficacy of ALT in Nigerians. ALT is safe and effective in reducing IOP in Nigerians. KEY MESSAGES: ALT is safe and effective in reducing intraocular pressure in this population of Nigerians. FUNDING: The present study did not receive any funds.

Effect of Cyclopentolate on In Vivo Schlemm Canal Microarchitecture in Healthy Subjects.

PURPOSE: To characterize the in vivo effect of cyclopentolate on the microstructure of Schlemm canal (SC) in healthy eyes. METHODS: For healthy subjects, 81 serial horizontal enhanced depth imaging optical coherence tomography B-scans (interval between scans, ∼35 µm) of the nasal corneoscleral limbal area were obtained before and 1 hour after cyclopentolate 1% administration in 1 eye. The structures of aqueous and blood vessels in each scan were used as landmarks to select 50 overlapping scans between the 2 sets of 81 serial scans (before and after cyclopentolate administration). The SC cross-sectional area was measured in each of the 50 selected scans. After 3-dimensional reconstruction, SC volume was determined. RESULTS: Twelve eyes (12 healthy subjects) were imaged successfully before and after cyclopentolate administration. Mean age was 27.8±4.9 years (range, 25 to 38 y). Following cyclopentolate administration, mean intraocular pressure did not change significantly (13.9±1.5 to 14.2±1.5 mm Hg; P=0.19). Mean SC cross-sectional area decreased by 17%, from 3563±706 to 2959±460 µm (P<0.001). Mean SC volume in the overlapping area (approximately 1.7 mm of circumferential length of SC) decreased from 6,164,061±1,220,787 to 5,119,462±794,763 µm (P<0.001). The decrease in the mean SC cross-sectional area after cyclopentolate administration was greater in eyes with larger baseline SC cross-sectional area (P<0.001, R=0.873). CONCLUSIONS: Cyclopentolate causes a reduction in SC dimensions in healthy eyes. Future studies are warranted to determine the exact mechanism(s) of this change.

Stargadt's disease in two Nigerian siblings.

Stargardt's disease is an inherited macular dystrophy that is transmitted in an autosomal recessive or dominant pattern. The disorder is typically characterized by impairment of central vision, with onset around the first 10-20 years of life. Stargardt's disease is rare in sub-Saharan Africa. This is probably the first reported case in the subregion. We present two siblings with the disease. Presentation, pathophysiology, and management modalities are discussed.