cabeman – Global Sight Alliance

Corneal Transplantation in the Developing World

cabeman — Tue, 14 Mar 2023 15:12:29 +0000

The case against most corneal transplants in low-income countries.

The problem with corneal transplants in the developing world is that sometimes they are not needed, might result in more eye problems, and often no follow-up care.

It is fairly easy to obtain corneal tissue and bring in a capable ophthalmic surgeon to do the corneal surgery. That’s the easy part. Post-op everyone is congratulating themselves on a clear transplant. But the problem is there often is no post-op care. The patient is often not able to travel for any post-op care, no matter what you think you have set up.

Usually, the only drops the post-op patient will ever have is what you give them on discharge. They probably will not be able to obtain anymore, much less once daily for life as many corneal surgeons recommend post-penetrating keratoplasty. The patient may well not be able to purchase the drops, and the nearest pharmacy could be hours away on foot. If there is any problem ( broken suture, rejection, iritis, ocular hypertension, dehiscence, ulcer, etc, ), it is quite unlikely the patient will quickly see an ophthalmologist, and, if so only after a month or so when the prognosis is now quite poor. And so with any problem, it is possible the graft could fail. Even if the initial post-op concern ( ? broken suture ) was minor.

I would suggest if the patient pre-op has 20 / 70 or better in the other ( good ) eye, then don’t do a corneal transplant. If you take an eye ( cornea ) that has an old scar, do a transplant, then a graft rejection, and later bullous keratopathy ( pain, tearing, redness ), then you have not made the patient better, but worst. I have seen this and have written about this previously.

Years ago, when I was the only ophthalmologist full-time in southern Malawi ( 4 million population ) ) a young girl showed up ( with her mother ) with bullous keratopathy from having had a keratoplasty done at an airport in Kenya. I hospitalized her as she had pain, redness, tearing, photophobia, etc. Her well-meaning ophthalmic surgeons had not made her better but worst. Certainly less likely now to snag a husband. The vision in the other ( good ) eye without any correction was 20/20. The mother stated she had previously had an old quiet corneal scar. Terrible. Using North American criteria for penetrating keratoplasty consideration is often not appropriate for the developing world. Many visiting ophthalmic surgeons ( volunteers ) never understand that fully. It took me initially about 6 months of living and working in Tanzania to realize a lot of my western medicine training ( beliefs ) were simply not appropriate for the developing world.

What would really be of interest if you went back 6-12 months after the initial keratoplasties, and, on the patients, you can run down, and record their presenting visions, not their best correction acuity but how they showed up. Record the presenting vision with both eyes open and then each eye separately. Many post-op keratoplasty patients, often have 2 – 3 diopters of cylinder even with a clear graft, so without any correction, what’s the post-op presenting vision?

Don’t get me wrong there are many patients needing a penetrating keratoplasty, but not if the other eye already sees well. Let me give you an example. If you have a patient with bilateral poor vision ( corneal scars ), then a keratoplasty may be indicated. Or perhaps an only eye if the pre-op vision is quite poor. Maybe. Try not to make the patient worst, you know first, do no harm. An Argon laser can often be used to re-make the anterior chamber ( pupilloplasty, etc. ) and improve the vision.

Of course, many developing world patients have poor vision due to bullous keratopathy post-cataract surgery, so endothelial keratoplasty may well be indicated. Difficult to have ophthalmologists show up for endothelial keratoplasty with proper instruments. Unfortunately one of the leading causes of poor vision in the developing world is poor vision post-cataract surgery.

Wealthy patients who already have family in the States or elsewhere in the industrialized world might do better traveling to the States / western Europe where their family members already live. Better post-op options/care.

Anyway, these are my thoughts about penetrating keratoplasty surgery in low-income countries. Some of you may disagree with my opinions.

Suggestions for Doing Outreaches with Local Eye Workers

cabeman — Fri, 27 Jan 2023 14:51:53 +0000

Below are teachable suggestions if you are doing outreach with local eye workers

Always take reading glasses as many eye patients in rural outreach clinics will simply need/want readers. ”I can’t see close up” was the chief complaint.
Topical NSAIDs — ketorolac ( Acular ), diclofenac ( Voltaren ), bromfenac (Xibrom ), flurbiprofen ( Ocufen ), nepafenac ( Nevanac ), etc. are usually helpful for “ allergic conjunctivitis” which is quite common in the developing world —itchy eyes, red eyes, tearing, mild discomfort, etc. Safer than topical steroids. Take NSAID drops with you if possible  cold compresses, don’t rub, NSAID drops tid prn.
No matter how you are checking IOP, a difference of more than 3 mm is questionable and the IOP should be rechecked in both eyes. One of the readings might be incorrect. Yes, but which one? The different readings could be correct but need to recheck OU and encourage the patient not to squeeze. An IOP of over 25 probably merits having the patient come to the eye clinic for further evaluation, especially if the patient is black, elderly, diabetic, and/or has a family history of glaucoma/blindness.
Bring several ( bright ) flashlights on outreach. Probably good to bring two direct ophthalmoscopes, especially if they need to be recharged rather than just changing the batteries.
Use a Snellen chart having numbers or the tumbling E’s. Many patients are illiterate and can’t read letters but almost everyone can read numbers. If you can’t read numbers then you can’t count money.
The green light (red-free light ) on the ophthalmoscope is good for looking at retinal blood vessels and appreciating small hemorrhages / IRMA’s / early neovascularization. Diabetic retinopathy should not be in just one eye. If you see retinal hemorrhages, exudates, etc. in just one eye, the problem could be a retinal vascular event ( BRVO, etc. ) rather than secondary to their diabetes. If you see changes in one eye, then go back and look again closely in the other eye ( use green light ? ).
You can use a direct ophthalmoscope to look closely at the conjunctiva and/or the anterior chamber. It can be quite helpful. Get close to the patient’s eye and use a + 8 to +10 D setting and get the limbal vessels in focus. For the examiner, this might require a +8 or a +9 or a +10 setting. The key is to get close to the eye , use a lot of plus power ( + 9 D ? ), and get the limbus in focus.

Remember you are not trying to visualize the retina ( posterior pole ) but the anterior segment. You might have to go up or down the plus scale ( black numbers ) a little and get slightly closer or further from the patient’s eye but you can see a lot. If you wanted to view the anterior segment what would you want? Well, some illumination and some magnification. That’s what you have with the direct ophthalmoscope. You can usually appreciate posterior synechiae, pupillary ruff differences, and sometimes rubeosis but what it is great at showing is posterior subcapsular opacity ( psc ) with a dilated pupil and a red reflex. Then you can really appreciate the cataract opacity/shadow in the red reflex.

In the field, sometimes a cataract doesn’t look so impressive but then looking with a dilated pupil and the direct ophthalmoscope will show the psc. The big question to ask the patient is if the vision is worst in bright light. Often yes with psc. I have used a portable slit lamp on many occasions, once doing an onchocerciasis survey in a rural rugged area of Malawi where we had to carry everything on our backs ( no roads) and walk in about a mile. This technique of using the direct ophthalmoscope compares well with a portable slit lamp for looking at the anterior segment.

Again these are pointers you can easily teach eye healthcare workers when doing outreach.

World Report On Vision 2019 -Part 2- Jan 2021

cabeman — Wed, 27 Jan 2021 12:48:31 +0000

Jan 2021 CHAPTER 2 Global magnitude: eye conditions and vision impairment lists the common eye conditions that can cause vision impairment. Blindness secondary to cornea problems / scarring is much more common in the developing world. Currently, more visual impairment globally from corneal opacities than diabetic retinopathy. In some countries / regions trachoma, which is an ongoing success story ( S.A.F.E. / azithromycin ) has yet to be eliminated. The prevalence of active trachoma is greatest in equatorial Africa. More common in women. Remember females ( mother / daughters / siblings ) usually have greater contact with small children who often are an ongoing source of active trachoma. That’s what we discovered in our extensive ophthalmic survey in southern Malawi ( Lower Shrine Valley ) many years ago .The rural women got repeated episodes of active trachoma ( conjunctivitis ) caring for the young children in the family. I have done my share of lid procedures for trichiasis but not sure I have ever done a trichiasis lid procedure for trachoma on a man. The tarsal rotation lid procedure for trichiasis appears the best and more long lasting. Incidentally in the States, I occasionally see a recent immigrant who has “ dry eye “ symptoms but everything looks OK except when you flip the lid you see subtle superior. palpebral scarring ( Arlt’s line ? ). I have felt perhaps the patient previously had several episodes of trachomatous conjunctivitis and wiped out their goblet cells ( mucus- producing ) so their pre-corneal tear film is not stable although it looks OK. Obviously I could be dead wrong on that.

As far as eye care services there was mention of availability, accessibility, affordability, and acceptability. Persistent inequalities remain between different subgroups of any population in accessing eye care services. In general, those not able to access eye care services as needed include people living in rural areas, those with low incomes, women, older people, people with disabilities, ethnic minorities, and refugees. Many of these issues are sometimes not a concern in the developed world so the depth of these ocular / logistical problems are not fully grasped. Inadequate access to eye care is a major cause of the unequal distribution of eye care. The closer you can bring your eye care to someone’s village, the more likely you are to help that patient, whatever your intervention ( eye surgery, glasses, medication, etc. ). Years ago in Tanzania, when we looked at where our surgical eye patients were coming from, a huge percentage lived less than 30 km from our eye hospital. In other words, we were not reaching most of our rural blind. As we all know, 90% of the world’s blindness are in the developing world.

Poor vision post-cataract surgery is unfortunately not uncommon. As I have mentioned previously, part of this problem is poor pre-op cataract evaluation which can result in disappointment / poor vision post-op. All white cataracts should not have cataract surgery. If you do that, you will most assuredly have some disappointed patients / poor vision post-op. Not a good way to encourage other patients from that village to come for cataract surgery.

Chapter 3 Addressing eye conditions and vision impairment, discusses strategies to address eye care needs — health-promoting, prevention, treatment, etc. As we know, cataract surgery is highly cost-effective. If at all possible the patient should not require numerous pre-op visits to the eye clinic before their cataract surgery. Cost and logistics of travel are major barriers to accessing eye care / surgery esp. for women. The more the pre-op eye patient has to come back / come back, then the less likely that patient will ever have their cataract operation -! come back for blood work, come back for an EKG, come back to see the nurse anesthetist pre-op, come back for the A-scan, etc. Madness.

Trauma is the most common cause of unilateral cataract. If small kids are left unsupervised, then the 5-year-old can hit the three years in the eye with a stick. When that happens that eye usually ends up with poor vision / phthisis. Unfortunately not an uncommon scenario. I do not think I have ever seen any limbal corneoscleral laceration ( ciliary body involvement ) that has recovered any useful vision. These eyes slowly head toward phthisis with a quite low IOP. Right?

When possible, with any visiting cataract surgical safari the outside visiting team should include the local ophthalmologist in the plans / activity so that the local community can see / appreciate that the local ophthalmologist / ophthalmic surgeon is part of the surgical team. It would be good if the in-country ophthalmologist gets to operate. Who knows, it could / should be a learning experience for everyone esp. the visiting surgeons if they do not routinely perform MSICS. With your visiting eye team, you don’t want to undermine the local ophthalmic infrastructure / personnel. You can certainly do that without even realizing that is what has happened.

You want, if possible, to promote the local ophthalmic surgeon as the local eye leader. I have seen / worked in situations where the local ophthalmologist is “ in charge” and often that can be a good model but obviously, that requires a dedicated local ophthalmologist. I have an ophthalmic friend ( now deceased ) who actually paid the local ophthalmologist to be part of his surgical team. Usually, it is a learning experience for everyone and this relationship may ensure reliable follow-up care as needed. Finding / making a lasting relationship / friendship with the local ophthalmic community could enhance everyone’s efforts / impact.

Of interest to me under common conditions amongst adults — Glaucoma treatment: General population screening for glaucoma is not currently considered to be cost-effective in most settings. A couple of times overseas, I have had to remind eye health workers that you really can not screen for glaucoma by just checking IOP. 50 – 50 chance of getting it right — or wrong. I think with eye screening, if you find patients with IOP over 23 mm then these patient should be told they might have glaucoma and when possible referred for further evaluation. Of course a good history might be helpful ( “any one in your family go blind” ? ). Even so, you can miss normal tension glaucoma patients and with a pronounced diurnal variation, as is often common with glaucoma, you may well miss the patient with ocular hypertension / glaucoma. I have repeatedly told eye health workers that checking the IOP a lot and recording the findings are often helpful and quite useful in diagnosing / treating glaucoma. Early glaucoma can be difficult to diagnosis correctly. With a large cup / disc ratio, then if available a OCT / RNFL test can be useful but remember that test may not always be correct. “ Don’t treat the red “. I certainly have seen many patients on one , two or more eye drops who I felt did not have glaucoma but only a large healthy cup / disc ratio. Glaucoma is probably the second leading cause of blindness worldwide. Glaucoma is such a loser that initially ( early on ) IAPB / Vision 2020 did not include glaucoma as a major issue / treatment concern as no one knew how to address glaucoma.. I have seen persons in their 20’s ( Haiti , sub-Saharan Africa ) that have already “ gone blind “ from glaucoma. Dishearting, the number of persons with glaucoma is four times higher in Asia than Africa.

Many of the references at the end of each chapter are of interest to anyone wanting more insight into where we are now and our peer-reviewed literature

Chapter 4 Successes and remaining challenges in eye care. This was written before the coronavirus pandemic so it will be interesting to see what happens in the post-coronavirus ophthalmic world. Many of our projections / long term plans for eye care international will need to be re-assessed in view of this pandemic and the adverse ocular affects in the developing world. Some of the plans / projected challenges might need to be re-thought. The next IAPB meeting should be of interest as we all try to re-group with the way forward.

Mention was made of the adoption of telehealth solutions. No doubt the pandemic has accelerated our use of tele-medicine. The possible of quickly having a second opinion on a complicated eye patient is obviously readily available with our ubiquitous smart phones and many portals including the AAO / ONE program. There is amazing amount of useful information available free through this portal. As most of us know, the International Centre for Eye Health has a twinning program that is ongoing and has helped to enhance the eye care possibilities / treatment strategies / training in many countries / in many eye departments / clinics. Obviously these exchanges are a two way learning opportunity for everyone. More and more informal tele-health consulting are occurring throughout the world. My tele-health problem that I have had with our ongoing diabetic ( retinal ) screening in rural South Carolina is ensuring the 5% with significant diabetic eye findings actually see an ophthalmologist for definite treatment / assessment. If they never get to see an ophthalmologist / eye surgeon , then the program has not accomplished what was hoped. How do you ensure the 5% at high risk , who may have transportation issues, etc. actually receive definitive retinal treatment for their PDR ?

There was mention that increasing life expectancy and population growth will result in additional visual needs / challenges. Some of the issues discussed in this report has been around for decades, many decades. We have made a lot of progress over the last 40 years and there is more to be done. From an ophthalmic standpoint, certainly the ongoing / adverse affects of this pandemic will need to be addressed in the coming years.

Chapter 5 Advancing universal health coverage through eye care. UHC means that all people have access to the health services they need, when and where they need them, without financial hardships. Well I suppose that is a worthy goal. I hope we will one day achieve that in the USA.

Chapter 6 Integrated people-centered eye care. Made reference that ophthalmology is particularly suited to telemedicine. Some of our human resource challenges include general shortages, maldistribution of workers, attrition, imbalances in skill composition and, at times, inadequate regulation. Reference was also made to losing eye care workers to other health sectors ( career opportunities ). That can be a problem if you invest time and efforts to train up the head eye nurse and she gets transfer to a different department as happened to me in Grenada.

Anyway, this concludes the world report. A lot of progress and many issues to be addressed.

The attached slides are of anterior staphyoma ( thinning and bulging ) secondary to old xeropthalmia / keratomalacia. The other slide show a child with a corneal scar secondary to trauma.

Peace,

Baxter McLendon