First-person perspective: Prof Shlomo Melamed on lessons from the Togo Glaucoma Project
On a recent trip to Togo, West Africa, my colleagues and I taught local ophthalmologists to perform selective laser trabeculoplasty in a model that we hope to see replicated throughout the region.
In Africa, glaucoma presents a unique and difficult problem, with a high prevalence compounded by economic barriers to essential medical care. Selective laser trabeculoplasty (SLT) is a potentially transformative modality in this setting, presenting an opportunity for quick, safe and effective long-term treatment. On a recent trip to Togo, West Africa, my colleagues and I taught local ophthalmologists to perform SLT in a model that we hope to see replicated throughout the region.
Glaucoma’s impact in Africa
Primary open-angle glaucoma (POAG) is prevalent in Africa and causes 15% of the blindness in individuals on the continent.1 A large study in urban West Africa showed the condition affects 6.8% of the population,2 believed to be a result of higher inherited risk of the disease evidenced by the higher prevalence of glaucoma among people of African descent around the world.3
In addition, in this population, the disease is often severe and rapidly progresses to damaging the optic nerve and visual fields.4 It is not unusual to see multiple family members affected by glaucoma, including some with total bilateral blindness.4 The devastating effect on families presents both a public health problem and a significant economic burden.4
Africans’ elevated genetic risk for high-tension glaucoma makes screening essential and management imperative. Unfortunately, many people face limited access to basic care and effective treatments. In West Africa, where my work has been focused, people are severely impoverished, with 36.8% of the population living in extreme poverty (on less than US $1.90 a day).5 This affects access to care in many ways:
- Countries have a shortage of ophthalmologists and ophthalmic caretakers, with just 2.5 ophthalmologists per million people in sub-Saharan Africa.6 There is also a chronic shortage of modern medical equipment for diagnosis and treatment7 and an unstable supply of glaucoma medications.8
- Ophthalmologists lack expertise in trabeculectomy and minimally invasive glaucoma surgeries.9
- For many patients, the cost of drug use for chronic conditions is too high, and using inefficient transportation systems to access limited care can be prohibitive.
As a result of all these issues, patients with glaucoma in West Africa
rarely receive the early diagnosis they need to prevent severe visual loss. More often, their disease is either undiagnosed or diagnosed at a late stage, and then undertreated. The result is a rapid progression of optic nerve damage and visual field constriction, ending in total blindness for too many people.
Can SLT help prevent blindness in West Africa?
As we look at ways to help preserve vision for West Africans suffering with glaucoma, one possible answer is SLT, which has a unique combination of efficacy and safety that addresses some of the problems identified in the region. For more than 20 years, SLT has been a proven and recognised tool for treating POAG.10
SLT’s mechanism of action is well known. Laser-tissue interaction triggers a chain of biological and biochemical reactions that result in enhanced outflow facility and reduction of intraocular pressure (IOP). SLT lowers IOP at least 20% and keeps patients off medications in about 75% of cases.10 SLT also has a superb safety profile, with only minimal and transient reddening of the eye in response to treatment.11,12 What is more, SLT is effective as a first-line therapy, often eliminating the need for medications. My colleagues and I were among the first to publish study results showing the safety and efficacy of SLT as the primary treatment,11 and the recent LiGHT study showed SLT was superior to medications as a primary treatment over 3 years.10 In addition, positive outcomes of SLT for people of African descent have been shown.13
Added to SLT’s safety and efficacy, the procedure is also quick, requiring about 2 minutes per eye in an office setting. That sets a lower bar for access to care, compared with surgery. There is no pain or discomfort, and patients resume regular activities immediately after treatment with no limitations.
With these advantages in mind, a group of ophthalmologists focused on introducing and enhancing use of SLT in Africa. Our vision was to use this excellent treatment modality to provide a safe and effective treatment for glaucoma without the need for chronic use of drugs or invasive surgery.
Carrying out an SLT pilot programme in Togo
Our team in Israel organised a special project in Lomé, the capital of and largest city in Togo, West Africa. Three ophthalmologists travelled to Lomé in October 2022. A generous donor contributed a Lumenis Digital Duet SLT-YAG laser to the Regional Hospital Center of Lomé Commune, delivered 2 weeks before our arrival.
Several months in advance, our team worked with the chief medical officer of Togo and his professional team to outline the project’s concept and primary goals. We wanted to implement the use of SLT as a tool for treating patients with elevated IOP and uncontrolled glaucoma. We set two main targets: 1) to educate Togolese ophthalmologists and ophthalmic care workers about SLT and its role in treating glaucoma and 2) to examine as many patients as possible in the 6 days our team spent at the hospital.
Our educational efforts were met with enthusiasm. The 14 local ophthalmologists and 10 caretakers who participated in the project were knowledgeable, motivated to learn and eager to master the SLT procedure to treat as many patients as possible. The education programme included lectures about SLT, as well as practical technical instruction and demonstrations with real patients.
During our stay, we examined 520 patients, many of whom were referred to us in advance by local ophthalmologists. Many of the patients had already received a diagnosis of glaucoma and had been treated with drugs. Of those we examined, 102 people required SLT treatment per the usual criteria of IOP elevated above 21 mm Hg despite or without topical treatment. The fact that nearly 20% of patients required SLT—a high percentage compared with what we see at home—underscored the severity of glaucoma in Togo.
When we began doing SLT, I treated the patients while the local ophthalmologists watched through the Digital Duet’s video system. After
2 days, they mastered the principles of therapy and started treating patients, first under my watch and later with complete independence.
We could only evaluate the success of SLT in the acute postoperative period, but the results were positive. Within 1 hour after SLT, in 90% of patients the IOP was lowered by 10% to 30% from baseline. Such a prompt acute response is a good prognostic sign and is encouraging for the future of SLT in Africa.
A model for the future
Following the success of the project in Togo, where clinical outcomes were positive and our Togolese colleagues adopted SLT technology to battle the challenges of glaucoma in their country, we hope that similar programs will be adopted in other African countries.
Having experience with many SLT lasers over the decades, our team found that the Digital Duet laser was appropriate for this project. Exceptional optics and comfortable ergonomics make the system well suited to new users, and the integrated video system that aided our education process could help ophthalmologists continue to fulfil the need for efficient training. It is also a reliable and heavy-duty device, suggesting durability that is well suited to economically challenged locations.
Our team was also grateful for the coordination provided by Togo’s chief medical officer and local ophthalmologists in Lomé. Through professional networks like these, our team hopes that the educational process will continue in Togo and throughout Africa.
