The Current Status of Glaucoma and Glaucoma Care in Sub-Saharan Africa

Early cataract surgery and affordable Sinskey hook goniotomy in Black and Afro-Latino glaucoma patients: a 6-month retrospective study

Aim

The purpose of this study was to determine the real-world efficacy of early phacoemulsification cataract surgery and goniotomy with a Sinskey hook in patients with glaucoma.

Methods

This study was conducted at Advanced Eye Care of New York, a private practice located in Manhattan, NY. This was a single-center, retrospective study of predominantly Black and Afro-Latino patients with glaucoma. These patients underwent early phacoemulsification cataract surgery and goniotomy using an affordable and reusable straight Sinskey hook (Ambler 200-μm tip). Patients who underwent the aforementioned procedure with 6 months of follow-up were included in this study. Investigated parameters were intraocular pressure, number of medications, mean deviation on visual field test, visual acuity, adverse events, and pre/postoperative spherical refractive error.

Results

Among all 38 eyes that were enrolled in the study and underwent surgery (goniotomy using a Sinskey hook with phacoemulsification), mean intraocular pressure was reduced from 16.45 mmHg at baseline to 13.24 mmHg at month 6, a 19.5% reduction. The mean number of topical intraocular pressure-lowering medications used was reduced from 1.81 at baseline to 0.52 at month 6, a 71% reduction in topical medications.

Conclusion

Combined early cataract surgery and goniotomy performed with a Sinskey hook is an affordable microinvasive surgery and an effective way to reduce intraocular pressure and the number of ocular hypertensive medications used in Black and Afro-Latino patients with primary open-angle glaucoma.

Selective laser trabeculoplasty versus 0·5% timolol eye drops for the treatment of glaucoma in Tanzania: a randomised controlled trial

BACKGROUND

Glaucoma is a major cause of sight loss worldwide, with the highest regional prevalence and incidence reported in Africa. The most common low-cost treatment used to control glaucoma is long-term timolol eye drops. However, low adherence is a major challenge. We aimed to investigate whether selective laser trabeculoplasty (SLT) was superior to timolol eye drops for controlling intraocular pressure (IOP) in patients with open-angle glaucoma.

METHODS

We did a two-arm, parallel-group, single-masked randomised controlled trial at the Eye Department of Kilimanjaro Christian Medical Centre, Moshi, Tanzania. Eligible participants (aged ≥18 years) had open-angle glaucoma and an IOP above 21 mm Hg, and did not have asthma or a history of glaucoma surgery or laser. Participants were randomly assigned (1:1) to receive 0·5% timolol eye drops to administer twice daily or to receive SLT. The primary outcome was the proportion of eyes from both groups with treatment success, defined as an IOP below or equal to target pressure according to glaucoma severity, at 12 months following randomisation. Re-explanation of eye drop application or a repeat SLT was permitted once. The primary analysis was by modified intention-to-treat, excluding participants lost to follow-up, using logistic regression; generalised estimating equations were used to adjust for the correlation between eyes. This trial was registered with the Pan African Clinical Trials Registry, number PACTR201508001235339.

FINDINGS

840 patients were screened for eligibility, of whom 201 (24%) participants (382 eligible eyes) were enrolled between Aug 31, 2015, and May 12, 2017. 100 (50%) participants (191 eyes) were randomly assigned to the timolol group and 101 (50%; 191 eyes) to the SLT group. After 1 year, 339 (89%) of 382 eyes were analysed. Treatment was successful in 55 (31%) of 176 eyes in the timolol group (16 [29%] of 55 eyes required repeat administration counselling) and in 99 (61%) of 163 eyes in the SLT group (33 [33%] of 99 eyes required repeat SLT; odds ratio 3·37 [95% CI 1·96-5·80]; p<0·0001). Adverse events (mostly unrelated to ocular events) occurred in ten (10%) participants in the timolol group and in eight (8%) participants in the SLT group (p=0·61).

INTERPRETATION

SLT was superior to timolol eye drops for managing patients with open-angle high-pressure glaucoma for 1 year in Tanzania. SLT has the potential to transform the management of glaucoma in sub-Saharan Africa, even where the prevalence of advanced glaucoma is high.

FUNDING

Christian Blind Mission, Seeing is Believing Innovation Fund, and the Wellcome Trust.

TRANSLATIONS

For the Kiswahili, French and Portuguese translations of the abstract see Supplementary Materials section.

Ocular Morbidity-A Critical Analysis to Improve Outpatient Services in an Eye Department in a Sub-Saharan Megacity

The aim of this study was to analyse outpatient services in an ophthalmic clinic of a church-run hospital providing secondary level care in an African megacity, paying special attention to the poorest users of the services. The range of examination was reviewed from 500 patient records of all ages consecutively chosen on random days attending the outpatient department for the first time in order to optimize workflow and to analyse the offered treatment modalities. Mean age was 41.9 ± 21.9 years, and 53.6% of the patients were female. Of the patients, 74.8% presented with visual impairment. The most frequent findings were refractive errors (35.8%), presbyopia (21.2%), allergic conjunctivitis (14.0%), cataract (13.2%) and glaucoma (6.4%). Patient management consisted of optical treatment (49.6%), surgery (11.4%) and medical treatment (39.0%). These results show the importance of the demand in refractive services and the need to train specific service providers. Knowing the frequencies of common conditions enables more appropriate diagnostic and treatment strategies, e.g., the importance of refractive errors, and should lead to improvements in training, staffing, therapeutics and patient outcomes. This approach can be applied to many other outpatient services and should be evaluated in light of the city’s impoverished health outreach and educational situation.

Eyes of Africa: The Genetics of Blindness: Study Design and Methodology

BACKGROUND

This report describes the design and methodology of the "Eyes of Africa: The Genetics of Blindness," a collaborative study funded through the Human Heredity and Health in Africa (H3Africa) program of the National Institute of Health.

METHODS

This is a case control study that is collecting a large well phenotyped data set among glaucoma patients and controls for a genome wide association study. (GWAS). Multiplex families segregating Mendelian forms of early-onset glaucoma will also be collected for exome sequencing.

DISCUSSION

A total of 4500 cases/controls have been recruited into the study at the end of the 3rd funded year of the study. All these participants have been appropriately phenotyped and blood samples have been received from these participants. Recent GWAS of POAG in African individuals demonstrated genome-wide significant association with the APBB2 locus which is an association that is unique to individuals of African ancestry. This study will add to the existing knowledge and understanding of POAG in the African population.

Comparing posture induced intraocular pressure variations in normal subjects and glaucoma patients

AIM

To compare the posture-induced variations in intraocular pressure (IOP) between the primary open angle glaucoma (POAG) and non-glaucomatous eyes.

METHODS

A case-controlled age matched study was conducted in 55 successive newly diagnosed POAG and 56 non-glaucomatous patients seen in glaucoma clinic and general outpatient eye clinic in the Alex Ekwueme University Teaching Hospital, Abakaliki. The IOPs of eligible correspondents were measured with Perkin's hand-held tonometer in the sitting, supine flat and supine with pillow positions respectively. Measurement of IOP in each position was done after 15min of assuming such posture.

RESULTS

The IOP difference between the sitting and supine flat position was significantly higher in the POAG than non-glaucoma subjects (7.68±2.08 vs 4.03±0.13 mm Hg, P<0.001). The IOP difference between the sitting and supine with pillow positions was 2.61±1.49 mm Hg for POAG and 1.44±0.70 mm Hg in non-glaucoma (P<0.001), while difference between supine flat and supine with pillow positions was 5.07±2.24 mm Hg in POAG and 2.59±0.66 mm Hg in non-glaucomatous patients (P<0.001).

CONCLUSION

Greater variations in posture induced IOP occurred in POAG patients than non-glaucomatous. The posture induced IOP variation is lowest in the sitting position and highest in the supine flat position. Evaluation of posture induced IOP changes may be an important tool in the management of glaucoma.

Crystalline lens changes after selective laser trabeculoplasty in Afro-Caribbean patients with open-angle glaucoma; report 4 of the West Indies Glaucoma Laser Study (WIGLS)

PURPOSE

To characterize changes in nuclear, cortical, and posterior subcapsular lens opacities after selective laser trabeculoplasty (SLT) in Afro-Caribbean eyes with primary open-angle glaucoma (POAG).

SETTING

Three clinical practices, Saint Lucia and Dominica.

DESIGN

Prospective case series.

METHODS

Patients with POAG in the West Indies Glaucoma Laser Study (WIGLS) had 360-degree SLT after medication washout. No antiinflammatory therapy was used after SLT. Nuclear, cortical, and posterior subcapsular lens opacities were graded through dilated pupils using the Lens Opacification Classification System III (LOCS III) at baseline and 12, 24, and 36 months after SLT, with the grader masked to all previous values after baseline assessment. Changes in opacity scores from baseline were evaluated using paired t tests.

RESULTS

Seventy-two patients (142 phakic eyes) were evaluated. The mean (±SD) baseline LOCS III opacity scores in right eyes and left eyes, respectively, were 2.44 ± 1.23 and 2.40 ± 1.16 (nuclear), 0.39 ± 1.08 and 0.30 ± 0.85 (cortical), and 0.22 ± 0.59 and 0.15 ± 0.36 (posterior subcapsular). Other than a small improvement in bilateral nuclear opacity scores at 12 months, no statistically or clinically significant changes in any opacity score occurred in either eye up to 36 months postoperatively. Three eyes (2.1%) with preexisting lens opacities had cataract surgery for progressive lens changes at 3 months, 21 months, and 26 months, respectively, after SLT.

CONCLUSIONS

Selective laser trabeculoplasty was not associated with clinically significant changes in nuclear, cortical, or posterior subcapsular lens opacities in glaucomatous Afro-Caribbean eyes. The rate of cataract surgery is consistent with reported rates from longitudinal natural history studies in Caribbean and non-Caribbean populations.

West Indies Glaucoma Laser Study (WIGLS) 3. Anterior Chamber Inflammation Following Selective Laser Trabeculoplasty in Afro-Caribbeans with Open-angle Glaucoma

PRECIS

In the absence of prophylactic anti-inflammatory therapy, anterior chamber inflammation (characterized by cells and less commonly flare) is minimal and transient after selective laser trabeculoplasty in Afro-Caribbean glaucoma patients.

PURPOSE

The purpose of this study was to characterize the prevalence, severity, and duration of anterior chamber inflammation (cells and flare) following selective laser trabeculoplasty (SLT) in Afro-Caribbean eyes with primary open-angle glaucoma (POAG).

METHODS

In total 144 eyes of 72 POAG patients underwent first-time 360-degree SLT treatment following washout of all topical medications in the prospective West Indies Glaucoma Laser Study. No anti-inflammatory therapy was used post-SLT. Anterior chamber cells and flare were characterized pre-SLT after medication washout, and 1 week, 6 weeks, and 3, 6, 9 and 12 months post-SLT using the standardized methodology described by the Society for Uveitis Nomenclature (SUN) in which cells and flare are each graded on a scale of 0-4+ using specific slit-lamp settings.

RESULTS

Mean cell scores in both right and left eyes rose significantly (P<0.0001) from baseline to week 1 after SLT before returning to baseline values at all subsequent time points. Mean flare scores in right eyes (P=0.0185) but not left eyes (P=0.1816) rose from baseline to week 1 after SLT before returning to baseline values at all subsequent time points. Cells appeared in 40.3% of eyes and flare appeared in 9.7% of eyes after SLT. One subject developed bilateral symptomatic anterior iritis one day postoperatively and reported a previously undisclosed history of recurrent iritis; the iritis resolved with topical steroid therapy.

CONCLUSIONS

SLT in Afro-Caribbean people with POAG is associated with mild, short-lived and self-limited anterior chamber inflammation. Routine anti-inflammatory therapy to suppress posttreatment inflammation after SLT is unnecessary in this population.

The Rationale for Selective Laser Trabeculoplasty in Africa

Glaucoma is the leading cause of irreversible blindness in Africa. The condition is treatable but not curable. There are numerous obstacles to glaucoma care in Africa, including availability, accessibility and affordability of treatments, as well as medication nonadherence among patients. Medical therapy is costly relative to the average income in Africa and it requires daily self-dosing by patients. Surgery is of limited availability in many regions in Africa, and a high proportion of patients refuse surgery because it is expensive. Selective laser trabeculoplasty (SLT) proves to be a favorable alternative to medical or surgical care, as it is highly effective and safe in people of African descent, more cost-effective than medical therapy, quick and easy to perform, and portable. The procedure also requires no postoperative care, thus obviates the issue of nonadherence. In uncontrolled studies, SLT has a high response rate and it lowers intraocular pressure by 30% to 40%, which exceeds the goal in international guidelines for initial therapies. The African Glaucoma Consortium (AGC), a member-driven stakeholder collective, has been formed in part to develop the infrastructure for continent-wide improvements in glaucoma care. It embraces SLT as a potential key tool in their development plans. The mission of AGC includes improving clinical care by educating existing and new health care professionals to expand the provider network, by conducting trials to identify optimal care strategies for glaucoma in Africa, and by facilitating the development of an integrated network of Centers of Excellence to bring SLT and other crucial glaucoma therapies to communities throughout Africa.