Diagnosis, Detection and Treatment of Glaucoma in Africa

Even in high-income countries, up to half of glaucoma is undiagnosed. In low and middle-income countries only a small proportion is detected before patients go blind. Tests for detecting glaucoma include the use of visual field machines which are expensive and not accessible in most low-income settings.

After being detected, glaucoma requires life-long follow-up which is often challenging. Treatment is complex and needs to be monitored regularly.

There is currently a paucity of evidence for treatment and follow-up strategies specifically tailored for African countries.

 

Glaucoma Detection Study

In Tanzania we have been testing a low-cost, portable glaucoma detection system which is easily performed and has good reliability and patient satisfaction. The study has been taking place at a hospital in Tanzania, with a parallel trial happening in the UK.

Participants are patients attending ophthalmology outpatient appointments, whose eyesight ranges from normal, healthy eyes to advanced glaucoma.

We have been trialling three tests that are quick and easy to perform and can be carried out using equipment which costs a fraction of what is currently required for glaucoma testing.

The three tests are:
1. Eyecatcher visual fields: have been developed which can be performed using a laptop screen and an eye-tracker which has shown good agreement with the current standard: Humphrey visual fields. The Humphrey Field Analyser is the most commonly used method for visual field testing and costs over USD 20,000. Using the Eyecatcher visual fields, participants follow a series of dots on the laptop screen with their eyes. The use of the eyetracker means they do not have to keep their head fixed on a chin-rest.

2. Peek Vision Contrast Sensitivity: this is performed using a smartphone. Participants indicate the orientation of letters on the screen. The letters get progressively dim until they cannot be seen anymore.

3. Optic nerve head photograph: this is performed using a portable camera, the Remidio camera. This has been CE marked and is FDA approved. It is in wide-spread clinical and research use and gives good quality photographs of the back of the eye.

The main objectives of the study are to see if the tests can be used to detect glaucoma, which combination of tests works best together, determining the repeatability of the tests, and how acceptable patients find them.

The main outcome measurement is if the glaucoma detection system can differentiate glaucoma patients versus healthy participants. Secondary outcomes include how well the Eyecatcher visual fields correlate with standard Humphrey fields.

Acknowledgements

We would like to thank the International Glaucoma Association (now Glaucoma UK) for funding, and Kilimanjaro Christian Medical Centre and Mid Cheshire NHS Hospitals for their partnership.

 

Early Diagnosis of Glaucoma in West Africa

In West Africa, glaucoma can be more aggressive compared to other places, often affecting younger people. Individuals frequently present too late with high eye pressure and advanced irreversible vision loss. Preventing blindness from glaucoma requires detecting it before it is symptomatic and implementing treatment in time to stop sight loss.

This project, based in Nigeria, aims to evaluate affordable, portable methods for detecting glaucoma at an earlier stage, before vision is lost. We have tested these methods against the gold standard of glaucoma diagnosis in a hospital setting, before applying them to community settings in Abuja, Nigeria.

It is hoped that the results of this study can contribute to improving glaucoma outcomes for people in West Africa by providing faster, cheaper and more accurate diagnosis and referral for treatment. As well as the results, the study strengthens capacity including training research assistants, a West African PhD ophthalmologist and post-doctoral researchers. It will nurture a network of academic clinicians seeking to address this major eye health challenge.

Acknowledgements

We would like to thank Velux Stiftung for funding this project and their continued support.

 

Improving Glaucoma Care in Tanzania

This project, based in Tanzania, will include two initiatives:

  1. Conducting training courses for eye health staff in the community to promote earlier detection of people at risk of irreversible sight loss from glaucoma and improve follow-up and treatment
  2. Developing effective ways to increase awareness and knowledge about glaucoma among patients and their relatives

Dr. Einoti Matayan, an ophthalmologist working at the Kilimanjaro Christian Medical Centre Eye Department, will undertake a PhD as part of the programme, becoming the project manager and local principal investigator for the studies.

The project will involve:

  • Baseline studies to understand health-seeking behaviour, knowledge, attitudes and practices of people at risk of glaucoma or with manifest glaucoma and their relatives
  • Mapping of current glaucoma care options and different types of eye care cadres and their range of work
  • Training relevant staff to detect patients with glaucoma and improve accessibility and affordability of follow-up examinations
  • Equipping eye centres with appropriate devices
  • Developing knowledge materials (for example leaflets, patient reminders etc)

The long-term impact of the project and its results will be improved detection, treatment and care of people with glaucoma in this region, which can then provide a template for the rest of Tanzania and elsewhere.

Acknowledgments

We would like to thank Christian Blind Mission for the funding for this project and their continued support.

 

Laser treatment for Nigeria

This study, based in Bauchi, Nigeria evaluates the feasibility and effectiveness of 3 types of laser for patients with glaucoma. It compares SLT (Selective laser trabeculoplasty) with MLT ( Micropulse laser trabeculoplasty) in patients with high intraocular pressure due to glaucoma. In patients for whom pressure remains high following this laser they are offered a third laser (Transcleral cyclodiode laser) which treats the ciliary body and reduces the production of aqueous humor.

This study will provide information on how effective, safe and acceptable initial laser treatment is for glaucoma in this population who present with very advanced glaucoma. It may provide an alternative to glaucoma surgery which is challenging in this region due to poor uptake and acceptance by patients and difficulty with long term follow up.

Acknowledgements

We would like to acknowledge Velux Siftung Foundation for their support for this project

 

Glaucoma Toolkits

ICEH have been integral to the development of a Toolkit for Glaucoma Management in Sub-Saharan Africa, and a subsequent Nigerian Glaucoma Guideline and Toolkit.

These toolkits are designed to guide ophthalmologists, glaucoma specialists and glaucoma care team members to set up integrated glaucoma care services in their own context, while strengthening health systems sustainably. They were created through collaboration with a broad range of stakeholders and experts in the field.

Recent activities have included using the guidelines to train doctors in glaucoma management in Nigeria, inviting 36 doctors from Nigeria’s 36 states to a workshop on the guidelines and its clinical recommendations. Twelve doctors then stayed on for surgical simulation training in glaucoma. In parallel, 8 ophthalmic nurses from 4 eye centres in Nigeria underwent training on diagnostic testing for glaucoma patients. They obtained skills in visual field testing, intraocular pressure measurement and OCT optic nerve imaging.

These toolkits have been made possible in part by the work of ICEH’s Glaucoma Network.

Acknowledgements

We would like to thank the Worshipful Company of Spectacle Makers and Global Health Partnerships (formerly THET) for funding, and Light for the World, COECSA, the West African College of Surgeons and National Eye Health Programme of Nigeria and Ministry of Health for their continued collaboration and partnership.