Minimally Invasive Bleb Surgery for Glaucoma: A Health Technology Assessment.

Background: Glaucoma is the term for a group of eye disorders that causes progressive damage to the optic nerve, which can lead to visual impairment and, potentially, irreversible blindness. Minimally invasive bleb surgery (MIBS) reduces eye pressure through the implantation of a device that creates a new subconjunctival outflow pathway for eye fluid drainage. MIBS is a less invasive alternative to conventional/incisional glaucoma surgery (e.g., trabeculectomy). We conducted a health technology assessment of MIBS for people with glaucoma, which included an evaluation of effectiveness, safety, the budget impact of publicly funding MIBS, and patient preferences and values. Methods: We performed a systematic literature search of the clinical evidence. We assessed the risk of bias of each included study using the Cochrane Risk of Bias 1.0 tool for randomized controlled trials (RCTs) and the Risk of Bias Assessment tool for Nonrandomized Studies (RoBANS) for comparative observational studies, and the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We conducted an economic literature search and we estimated the budget impact of publicly funding MIBS in Ontario. We did not conduct a primary economic evaluation due to the limited long-term effectiveness data. We summarized the preferences and values evidence from previous health technology assessments to understand the perspectives and experiences of patients with glaucoma. Results: We included 41 studies (2 RCTs and 39 comparative observational studies) in the clinical evidence review. MIBS may reduce intraocular pressure and the number of medications used, but we are uncertain if MIBS results in outcomes similar to trabeculectomy (GRADE: Moderate to Very low). Compared with trabeculectomy, MIBS may result in fewer follow-up visits and interventions, and adverse events (GRADE: Moderate to Very Low). MIBS may also reduce intraocular pressure and the number of antiglaucoma medications used, compared with other glaucoma treatments, but the evidence is uncertain (GRADE: Very low). Our economic evidence review identified two directly applicable studies. The results of these studies indicate that the cost-effectiveness of MIBS is highly uncertain, and the cost of glaucoma interventions are likely to vary across provinces. The annual budget impact of publicly funding MIBS in Ontario ranged from $0.11 million in year 1 to $0.67 million in year 5, for a total 5-year budget impact estimate of $1.93 million. Preferences and values evidence suggests that fear of ultimate blindness and difficulty managing medication for glaucoma led patients to explore other treatment options such as MIBS. Glaucoma patients found minimally invasive glaucoma surgery (MIGS) procedure beneficial, with minimal side effects and recovery time. Conclusions: Minimally invasive bleb surgery reduces intraocular eye pressure and the number of antiglaucoma medications needed, but we are uncertain if the outcomes are similar to trabeculectomy (GRADE: Moderate to Very low). However, MIBS may be safer than trabeculectomy (GRADE: Moderate to Very low) and result in fewer follow-ups (GRADE: Moderate to Very low). MIBS may also improve glaucoma symptoms compared with other glaucoma treatments, but the evidence is very uncertain (GRADE: Very low).We estimate that publicly funding MIBS would result in an additional cost of $1.93 million over 5 years. Patients who underwent MIGS procedures found them to be generally successful and beneficial, with minimal side effects and recovery time. We could not draw conclusions about specific MIBS procedures or long-term outcomes.

Rapid assessment of avoidable blindness and cataract surgery coverage among forcibly displaced Myanmar Nationals (Rohingya refugees) in Cox's Bazar, Bangladesh.

AIM: To determine the prevalence and causes of blindness, vision impairment and cataract surgery coverage among Rohingya refugees aged ≥ 50 years residing in camps in Cox's Bazar, Bangladesh. METHODS: We used the Rapid Assessment of Avoidable Blindness (RAAB) methodology to select 76 clusters of 50 participants aged ≥ 50 years with probability proportionate to size. Demographic and cataract surgery data were collected using questionnaires, visual acuity was assessed per World Health Organization criteria and examinations were conducted by torch, and with direct ophthalmoscopy in eyes with pinhole-corrected vision <6/12. RAAB software was used for data entry and analysis. RESULTS: We examined 3,629 of 3800 selected persons (95.5%). Age and sex adjusted prevalence of blindness (<3/60), severe visual impairment (SVI; >3/60 to ≤6/60), moderate visual impairment (MVI; >6/60 to ≤6/18), and early visual impairment (EVI; >6/18 to ≤6/12) were 2.14%, 2.35%, 9.68% and 14.7% respectively. Cataract was responsible for 75.0% of blindness and 75.8% of SVI, while refractive error caused 47.9% and 90.9% of MVI and EVI respectively. Most vision loss (95.9%) was avoidable. Cataract surgical coverage among the blind was 81.2%. Refractive error was detected in 17.1% (n = 622) of participants and 95.2% (n = 592) of these did not have spectacles. In the full Rohingya cohort of 76,692, approximately 10,000 surgeries are needed to correct all eyes impaired (<6/18) by cataract, 12,000 need distance glasses and 73,000 require presbyopic correction. CONCLUSION: The prevalence of blindness was lower than expected for a displaced population, in part due to few Rohingya being ≥60 years and the camp's good access to cataract surgery. We suggest the United Nations High Commissioner for Refugees include eye care among recommended health services for all refugees with long-term displacement.

Cataract Services are Leaving Widows Behind: Examples from National Cross-Sectional Surveys in Nigeria and Sri Lanka.

The Sustainable Development Goals aim to leave no one behind. We explored the hypothesis that women without a living spouse-including those who are widowed, divorced, separated, and never married-are a vulnerable group being left behind by cataract services. Using national cross-sectional blindness surveys from Nigeria (2005-2007; n = 13,591) and Sri Lanka (2012-2014; n = 5779) we categorized women and men by marital status (married/not-married) and place of residence (urban/rural) concurrently. For each of the eight subgroups we calculated cataract blindness, cataract surgical coverage (CSC), and effective cataract surgical coverage (eCSC). Not-married women, who were predominantly widows, experienced disproportionate cataract blindness-in Nigeria they were 19% of the population yet represented 56% of those with cataract blindness; in Sri Lanka they were 18% of the population and accounted for 54% of those with cataract blindness. Not-married rural women fared worst in access to services-in Nigeria their CSC of 25.2% (95% confidence interval, CI 17.8-33.8%) was far lower than the best-off subgroup (married urban men, CSC 80.0% 95% CI 56.3-94.3); in Sri Lanka they also lagged behind (CSC 68.5% 95% CI 56.6-78.9 compared to 100% in the best-off subgroup). Service quality was also comparably poor for rural not-married women-eCSC was 8.9% (95% CI 4.5-15.4) in Nigeria and 37.0% (95% CI 26.0-49.1) in Sri Lanka. Women who are not married are a vulnerable group who experience poor access to cataract services and high cataract blindness. To "leave no one behind", multi-faceted strategies are needed to address their needs.

Lucia and Beyond: Development of an Affordable Keratoprosthesis.

PURPOSE: Severe corneal disease contributes significantly to the global burden of blindness. Corneal allograft surgery remains the most commonly used treatment, but does not succeed long term in every patient, and the odds of success fall with each repeated graft. The Boston keratoprosthesis type I has emerged as an alternative to repeat corneal allograft. However, cost limits its use in resource-poor settings, where most corneal blind individuals reside. METHODS: All aspects of the Boston keratoprosthesis design process were examined to determine areas of potential modification and simplification, with dual goals to reduce cost and improve the cosmetic appearance of the device in situ. RESULTS: Minor modifications in component design simplified keratoprosthesis manufacturing. Proportional machinist time could be further reduced by adopting a single axial length for aphakic eyes, and a single back plate diameter. The cosmetic appearance was improved by changing the shape of the back plate holes from round to radial, with a petaloid appearance, and by anodization of back plate titanium to impute a more natural color. CONCLUSIONS: We have developed a modified Boston keratoprosthesis type I, which we call the "Lucia." The Lucia retains the 2 piece design and ease of assembly of the predicate device, but would allow for manufacturing at a reduced cost. Its appearance should prove more acceptable to implanted patients. Successful keratoprosthesis outcomes require daily medications for the life of the patient and rigorous, frequent, postoperative care. Effective implementation of the device in resource-poor settings will require further innovations in eye care delivery.

Eye donation and eye banking in India.

Corneal blindness is a priority condition under the National Programme for Control of Blindness and an important cause of avoidable blindness in India. A multipronged approach is needed to eliminate corneal blindness. Curable or treatable blindness requires a spectrum of care including medication, optical rehabilitation and corneal transplantation. Corneal transplantation is dependent on the availability of safe, donor eyes; however, there is scarcity of donor corneal tissues in India. To improve the eye banking system, the Government of India supports eye banks through recurring grants for operational costs and non-recurring grants for infrastructure costs. Strategic interventions by the government and non-governmental organizations include awareness by health promotion and education, community participation, sustainable source of donor cornea, quality medical standards, accreditation and endeavours to strengthen eye banking systems and procedures through training and research. A model eye banking system in India can be achieved only when it is linked with the targeted infrastructure proposed under 'Vision 2020: Right to Sight- India'. Considering these targets, there is a requirement of at least 20 eye bank training centres, 200 eye banks with corneal transplant facility (collection of nearly 500 corneas per year) and 2000 eye donation centres in the country. This would become a reality if the Hospital Cornea Retrieval Programme is strengthened at all private and government hospitals, uniform medical standards are made mandatory for all eye banks and eye donation centres and the process of registration and eye donation is simplified to enhance community participation.

Outcomes of Cataract Surgery in Urban and Rural Population in the South Indian State of Andhra Pradesh: Rapid Assessment of Visual Impairment (RAVI) Project.

OBJECTIVE: To assess the visual outcomes after cataract surgery among urban and rural population aged ≥40 years in the South India state of Andhra Pradesh. METHODS: A population based cross-sectional study was conducted in which 7800 subjects were sampled from two rural and one urban location. Visual Acuity was assessed and eye examination were performed by trained personnel. A questionnaire was used to collect personal and demographic information, and history of cataract surgery. Blindness and moderate Visual Impairment (MVI) was defined as presenting VA <6/60 and <6/18 to 6/60 in the better eye respectively. RESULTS: In total, 7378 (94.6%) were examined. Of these, 1228 eyes of 870 individuals were operated for cataract. The mean age of operated subjects was 63.7 years (SD: 10.7 years). Overall, 56.3% of those operated were women, 76% were illiterate and 42% of them were using spectacles after cataract surgery. Even after surgery, 12.2% of the operated eyes had MVI and blindness was seen in 14.7% of the eyes. A significantly higher proportion of subjects in urban area had good outcome as compared to those in the rural area (p = 0.01). Uncorrected refractive error (58.7%) was the leading cause of MVI, and posterior segment disease (34.3%) was the leading cause of blindness. On applying multiple logistic regression, risk factors for poor outcomes were age ≥ 70 years (OR: 1.9, 95% CI: 1.3-2.8), rural residence (OR: 1.3, 95% CI:1.0-1.8) and presence of aphakia (OR: 8.9, 95% CI: 5.7-13.8). CONCLUSIONS: Post cataract surgery, refractive errors remain an important correctable cause of MVI, in the south Indian state of Andhra Pradesh. The correction of refractive errors is required to provide good visual recovery and achieve the benefit of cataract surgery.

Perception and Attitude of a Rural Community Regarding Adult Blindness in North Central Nigeria.

AIM: To determine the perception and attitudes of a rural community regarding the etiology, prevention, and treatment of blindness in adults. METHODS: A cross-sectional, descriptive study was performed in a rural community in Kwara State, Nigeria using semi-structured questionnaire. All adults aged 40 years or older who were residents for a minimum of 6 months in the community were included. Data were collected on patient demographics, knowledge, attitude, perception, and use of the eye care facility. RESULTS: A total of 290 participants were interviewed. The male-to-female ratio was 1:2. Consumption of certain types of food was an important cause of blindness as perceived by 57.9% of the respondents, followed by supernatural forces (41.7%) and aging (19%). Sixty percent of respondents thought blindness could be prevented. Age (P = 0.04) and level of education (P =0.003) significantly affected the beliefs on the prevention of blindness. Most respondents (79.3%) preferred orthodox eye care, but only 65% would accept surgical intervention if required. The level of education significantly affected the acceptance of surgery (P = 0.04). Reasons for refusing surgery were, fear (64%), previous poor outcomes in acquaintances (31%), belief that surgery is not required (3%), and cost (2%). About 65% used one form of traditional eye medication or the other. Over half (56.6%) believed that spectacles could cure all causes of blindness. Of those who had ocular complaints, 57.1% used orthodox care without combining with either traditional or spiritual remedies. CONCLUSION: This rural Nigerian community had some beliefs that were consistent with modern knowledge. However, the overall knowledge, attitude, and perceptions of this community need to be redirected to favor the eradication of avoidable blindness. Although an eye care facility was available, use by the community was suboptimal. Age and the level of education affected their overall perception and attitudes.

Positioning of electronic subretinal implants in blind retinitis pigmentosa patients through multimodal assessment of retinal structures.

PURPOSE: To optimize methods for positioning subretinal visual implants, customizing their cable length, guiding them to the predetermined retinal position, and evaluating their performance. METHODS: Ten eyes of 10 patients (6 male, 4 female, mean age 46.4 years) were investigated before implantation of a subretinal visual implant. The structural characteristics of the retina as well as the ocular dimensions were determined. Topographic images of the prospective implantation site were subdivided into grids of squares. Each square received a weighted score for suitability. The sum of the scores was calculated, and the region with the highest score was chosen for the implant. In each case, the implant's power supply cable length was calculated by means of magnetic resonance imaging. The planned and achieved positions before and after implantation were compared. RESULTS: The mean light sensitivity ratio between the area actually covered by the chip and that of the planned position was 90.8% with an SD of 11.4%. In two cases with almost perfect positioning, the computed ratio was 100%. Measurements showed that to achieve a 95% sensitivity rate the difference between the planned and achieved chip position must be less than 1.7 mm. Preoperative calculations of the intraocular cable length proved accurate in all cases. CONCLUSIONS: Preoperative evaluation of retinal structures and eye morphology is useful for guiding a retinal implant to the designated area. It is a meaningful tool for planning and performing retinal chip implantation, and it optimizes personalized implantation. (ClinicalTrials.gov numbers, NCT00515814, NCT01024803.).

Prevalence, causes and socio-economic determinants of vision loss in Cape Town, South Africa.

PURPOSE: To estimate the prevalence and causes of blindness and visual impairment in Cape Town, South Africa and to explore socio-economic and demographic predictors of vision loss in this setting. METHODS: A cross sectional population-based survey was conducted in Cape Town. Eighty-two clusters were selected using probability proportionate to size sampling. Within each cluster 35 or 40 people aged 50 years and above were selected using compact segment sampling. Visual acuity of participants was assessed and eyes with a visual acuity less than 6/18 were examined by an ophthalmologist to determine the cause of vision loss. Demographic data (age, gender and education) were collected and a socio-economic status (SES) index was created using principal components analysis. RESULTS: Out of 3100 eligible people, 2750 (89%) were examined. The sample prevalence of bilateral blindness (presenting visual acuity <3/60) was 1.4% (95% CI 0.9-1.8). Posterior segment diseases accounted for 65% of blindness and cataract was responsible for 27%. The prevalence of vision loss was highest among people over 80 years (odds ratio (OR) 6.9 95% CI 4.6-10.6), those in the poorest SES group (OR 3.9 95% CI 2.2-6.7) and people with no formal education (OR 5.4 95% CI 1.7-16.6). Cataract surgical coverage was 68% in the poorest SES tertile (68%) compared to 93% in the medium and 100% in the highest tertile. CONCLUSIONS: The prevalence of blindness among people ≥50 years in Cape Town was lower than expected and the contribution of posterior segment diseases higher than previously reported in South Africa and Sub Saharan Africa. There were clear socio-economic disparities in prevalence of vision loss and cataract surgical coverage in this setting which need to be addressed in blindness prevention programs.

Long-term visual outcome and aneurysm obliteration rate for very large and giant ophthalmic segment aneurysms: assessment of surgical treatment.

BACKGROUND: Standard endovascular therapy has shown little success in treatment of very large and giant ophthalmic segment aneurysms. We hypothesize that surgical treatment of these aneurysms yields better results in terms of visual function and aneurysm obliteration. METHODS: The Toronto Brain Vascular Malformation Study Group database was analyzed to retrieve patients treated surgically for very large (>15 mm) and giant aneurysms of the ophthalmic segment of the carotid artery. Preoperative data and postoperative long-term outcomes with specific consideration for visual function and aneurysm obliteration were evaluated. RESULTS: Of the 257 patients with ophthalmic and paraophthalmic aneurysms, 38 patients had very large or giant aneurysms. Twenty-one underwent surgical treatment; 19 had direct clipping; 1 had trapping, and 1 underwent trapping and bypass. Fifteen patients had unruptured and six had ruptured aneurysms. The mean follow-up period was 88 months. Six (28%) aneurysms had a small residual neck remnant. Of the 12 patients with documented preoperative visual deficit, 9 (75%) improved, 2 (16%) remained stable, and 1 (8%) worsened. Two patients had mild to moderate new visual deficit. Thus, the surgery-related visual complications were 14%. Eighteen patients (86%) had a good or excellent outcome (GOS IV and V). Presentation with prior visual deficit and poor neurological function were predictors of worse visual and clinical outcome, respectively (P = 0.02 and 0.01). CONCLUSIONS: There is considerable surgery-related risk for optic pathways during treatment of very large and giant ophthalmic segment aneurysms. Surgery, however, seems to be the treatment of choice in terms of overall visual outcome and aneurysm obliteration as compared to the current endovascular results in this subset of patients.

[Availability of patients living in rural areas, to have surgical method of treatment of cataract and glaucoma].

Using modern surgical treatment on patients that live in rural areas, with cataract and glaucoma is not sufficient. There is insufficient expertise of ophthalmologists, low level of human, logistical and financial resource support for eye hospitals, low level of motivation and socio-psychological problems among patients, creating a favorable situation in Ukraine for further growth of low vision and blindness in rural areas. Institutional solutions of existing problems are proposed.

Cataract surgery: limitations and barriers in Makurdi, Benue State.

BACKGROUND: Cataract is amenable to surgery; despite this affected patients do not always embrace or accept cataract surgical intervention. The study aims to ascertain the factors responsible for this negative attitude towards cataract surgery by affected patients. METHODS: A prospective study was carried out with an interview assisted questionnaire, parameters assessed were duration of blindness before presentation, insight into the cause of cataract, awareness of the available treatment, knowledge of where to go for treatment and possible barriers to surgical treatment was administered to all consecutive patients aged 40 years and above whose cause of visual impairment and blindness is principally due to cataract for a period of one year (January 2007 December 2007). RESULTS: Senile cataract constituted 2.6% (180) of all the patients aged 40 years and above. Duration of blindness before presentation ranged from 6 to 84 months. Majority of the patients (65%) were aware that surgical intervention was the answer to their visual dysfunction. CONCLUSION: Although, affected patients are knowledgeable that surgical intervention was the answer to their visual dysfunction, they do not readily embrace surgical intervention for diverse reasons.

Case payment and the adoption of new technology: an empirical study of cataract surgery in Taiwan.

BACKGROUND: Case payment for cataract surgery with Government Employee Insurance (GEI) was implemented at Chang Gung Memorial Hospital (CGMH) in March 1994, and fee-for-service (FFS) was retained for cataract inpatients with or without other health insurance. We examined the impact of this change in the reimbursement policy from FFS to case payment on the health care provider's practice behavior towards a new emerging technology, using cataract surgery as an example. METHODS: Secondary data analysis was performed using 1 year of CGMH data before (period 1, from March 1993 to February 1994) and after (period 2, from March 1994 to February 1995) implementing the new policy. Inpatient records for cataract surgery using either extracapsular cataract extraction (ECCE, the old technology) or phacoemulsification (Phaco, the new technology) were included. Logistic regression models were employed to assess how case payment affected the health care provider's adoption of new technology. RESULTS: The percentage of cases treated using the new Phaco technology grew from period 1 (6.6%) to period 2 (23.6%) among all 4 study groups, despite Phaco being more expensive than ECCE. More importantly, the increment ratio of Phaco use from periods 1 to 2 was the smallest for GEI patients (3.26-fold) when compared with the other 3 groups (4.16-5.29-fold). CONCLUSIONS: Both new technology and cost containment strategies should be taken into account when setting up a reimbursement policy.

Reasons for poor cataract surgery uptake - a qualitative study in rural South Africa.

OBJECTIVES: To understand the reasons for poor cataract surgery uptake in people with blindness or severe visual impairment in rural South Africa. METHODS: A qualitative analysis of detailed, domiciliary interviews with a community-based random sample of elderly Zulus who were blind or severely visually impaired as a result of operable cataract, who had previously been invited for surgery but had failed to attend. RESULTS: Fear of surgery and a fatalistic attitude to the inevitability and irreversibility of blindness in old age were the main reasons for failure to attend for surgery. There was a lower level of disability and perceived need than had been assumed for people with such poor visual acuity. Non-surgical western style health care for systemic illness was common but few patients had sought any form of assistance for their poor vision. Issues of cost and accessibility were relatively unimportant. CONCLUSION: Provision of affordable and accessible cataract surgery for the blind and severely visually impaired members of a community does not guarantee that it will be taken up. Other barriers to surgery may be revealed when practical issues such as cost and accessibility are addressed. Perceptions of visual disability among subjects with cataract may differ from simple objective clinical standards.

Vision loss among diabetics in a group model Health Maintenance Organization (HMO).

PURPOSE: To report the management of diabetic retinopathy in one group model health maintenance organization and assess the quality of care. METHODS: Cross-sectional study. A chart review of 1200 randomly identified patients with diabetes mellitus, continuously enrolled for 3 years in Kaiser Permanente (KP) Southern California, the largest provider of managed care in Southern California, was performed. A total of 1047 patients were included in the analyses. Patient characteristics as well as information from the last eye examination were abstracted. Charts from patients with visual acuity less than 20/200 in their better eye (legal blindness) were selected for extensive chart review to determine the cause of visual loss and the antecedent process of care. T tests or the Wilcoxon rank sum test was used to compare continuous variables. The chi(2) test or the Fisher exact test was used to compare categorical variables. All analyses were performed on the Statistical Analyses System (SAS Institute, North Carolina). RESULTS: Our study population of 1047 diabetic patients was 51.7% male, had a mean age of 60.4 years, a mean duration of diabetes of 9.6 years, and a mean hemoglobin A1c of 8.3%. During the study period, 77.5% of patients received a screening eye examination with examination by an ophthalmologist, an optometrist, or review of a retinal photograph. Of those with a visual acuity assessment (n = 687, 65.6% of 1047), 1.5% had visual acuity of 20/200 or worse (legally blind) in the better eye, while 8.2% had this level of visual acuity in the worse eye. Of eyes with new onset clinically significant macular edema and visual acuity < 20/40, 40% had documentation of focal laser performed within 1 month of diagnosis. Of eyes with vitreous hemorrhage and visual acuity < 20/40, 50% had documentation of vitrectomy. Among eyes that had vitrectomy, over 80% had this procedure within 1 year of diagnosis of vitreous hemorrhage. CONCLUSIONS: The current report is the largest study of diabetic retinopathy outcomes among patients enrolled in a prepaid health plan. Further research is necessary to investigate the impact of managed care on health outcomes.

Cataract blindness--challenges for the 21st century.

Cataract prevalence increases with age. As the world's population ages, cataract-induced visual dysfunction and blindness is on the increase. This is a significant global problem. The challenges are to prevent or delay cataract formation, and treat that which does occur. Genetic and environmental factors contribute to cataract formation. However, reducing ocular exposure to UV-B radiation and stopping smoking are the only interventions that can reduce factors that affect the risk of cataract. The cure for cataract is surgery, but this is not equally available to all, and the surgery which is available does not produce equal outcomes. Readily available surgical services capable of delivering good vision rehabilitation must be acceptable and accessible to all in need, no matter what their circumstances. To establish and sustain these services requires comprehensive strategies that go beyond a narrow focus on surgical technique. There must be changes in government priorities, population education, and an integrated approach to surgical and management training. This approach must include supply of start-up capital equipment, establishment of surgical audit, resupply of consumables, and cost-recovery mechanisms. Considerable innovation is required. Nowhere is this more evident than in the pursuit of secure funding for ongoing services.