Eye Diseases Seen in Sub-Saharan Africa
Colleagues from India published recently a RCT, which evaluated subconjunctival anesthesia for manual small incision cataract surgery.
Not surprisingly, it does not provide akinesia. However, its anesthesia is sufficient for more or less comfortable surgery. It’s only obstacle is a chemisis, which is especially disturbing for novice surgeons.
Manual small incision cataract surgery (MSICS) is a gold standard for high-volume cataract services in developing countries. Since recently (with the rise of global ophthalmology concept) it has become part of the best ophthalmology training programs in the US and across the world. It is an absolutely brilliant and gentle technique, which is especially suited for premature, mature and hypermature cataracts, as well as traumatic and congenital cataracts. But one can also apply the same technique to operate on immature cataracts. Here it won’t be so fast, as the aspiration of sticky cortex will take its time with Simcoe cannula. Nevertheless, all the stages are doable.
There are differences in capsulotomy diameter, which one needs for “normal” immature cataracts (~5-6 mm) and for hypermature cataracts (up to 9-10 mm!). In mature cataracts one has to use a dye (trypan blue), but also often to carefully decompress an elevated intralenticular pressure (which often fails and leads to capsular tear and/or “argentinian flag”-style tears)! This makes capsulotomy (and capsulorhexis as one of them) in mature cataracts more complex if compared to the one in immature “transparent” cataracts.
For MSICS I personally preferred mainly a so-called “can-opener” type of capsulotomy, as it is a) easier, b) faster, and c) safer. Once I had realized these benefits, I switched to this technique almost invariably. Can-opener is best for big mature nuclei and also for Morgagnian cataracts. I am, however, aware, that can-opener is almost always not a good option for phaco. At the same time I found continuous curvilinear capsulorhexis (CCC) technique in transparent (immature) cataracts pretty easy to perform in comparison to intumescent hypermature cataracts. However, CCC is also possible by MSICS on mature cataracts. One can do it through both a tunnel or a paracentesis. A tunnel offers greater maneuverability, a paracentesis offers more stable anterior chamber.
For CCC in MSICS one can employ a) insuline syringe needle, b) Utrata forceps (gives the best control over rhexis!) and c) McPherson tying forceps. The latter is non-toothed and is a sort of improvisation, when the correct forceps is inavailable (often the case in Tropics!). In this video I depicted typical variants of CCC by mature and hypermature (and intumescent and Morgagnian!) cataracts, both uncomplicated and complicated cases. The can-opener technique is presented in two cases here and also in the other video of this channel.
* Some of the videos were screened at the earlier stage of my MSICS career. Some of the capsulotomies depicted here could have been managed better, and do not necessarily represent the best possible surgical technique. After I had bought Utrata capsulorhexis-forceps during my trip to the USA in early 2017, I never used McPherson for this purpose anymore. So, I highly recommend to purchase Utrata early in your MSICS career. The video will however be a good one for the MSICS beginners in the tropics, who often have to tackle the complex intumescent lenses with suboptimal instruments, and who still have the right to do mistakes 🙂 I would anyways appreciate your (also critical) comments.
Those of you, who just start with MSICS – Keep it up!
Thanks for watching!
Interesting paper on results of eye surgical camp in Tansania. The results of 42 surgeries show that only 14% of patients at the postoperative day 5-9 have gotten a visual acuity > 0,3. That is unusually low in comparison to our experience in Zambia and to the results published elsewhere in the literature. The case may be due to, as indeed stated in the paper, the highly complicated cases (i.e., also poor selection of cases), and occasionally the quality of the technique and instruments used.
Sumbawanga Augencamp follow-up Studie 2019
Results
A total of 42 postoperative patients from the eye camp could be examined within 5–9 days after cataract sugery. The following parameters were found: median postoperative visual acuity 0.26, spherical equivalent −2.82 dpt, astigmatism −2.2 dpt, axis 113°. Visual acuity >0.3 in 14.2% (WHO 80%), vision 0.1–0.3 in 62% (WHO 15%), vision <0.1 in 23.8% (WHO 5%). Prolonged healing time and intraocular irritation in 29% of the cases.
Conclusion
Although the vision improved, the results are sobering when taken in the context of the WHO guidelines. The postoperative refraction showed a myopic shift and an high level of astigmatism. The reasons are manifold: ocular comorbidities, limited diagnostic and therapeutic possibilities in a nonclinical setting. Other factors are the kind of training of the staff in the camp, the difficult circumstances and advanced findings. Consideration of the results of this study is imperative to be able to measure the quality of the work and to create the potential to make future improvements.
There is a good retrospective study from Nigeria showing that trends to operate only the advanced stages of cataract persist in Sub-Saharan Africa. That means that a patient with cataract would typically get his cataract removed only when they are blind (i.e. 0,05 or 3/60 and beliw, HM, LP etc.). In this context it is important to remember, that MSICS technique of cataract surgery is safer in premature and matute stages of cataract, which can influence the willingness to operate among surgeons.
Ther Adv Ophthalmol. 2019 Jan-Dec; 11: 2515841419886451.
Published online 2019 Nov 13. doi: 10.1177/2515841419886451
PMCID: PMC6854760
PMID: 31763621
Preoperative visual acuity of cataract patients at a tertiary hospital in sub-Saharan Africa: a 10-year review
Mary O. Ugalahi, Obioma C. Uchendu, and Linda O. Ugalahi
Mary O. Ugalahi, Department of Ophthalmology, College of Medicine, University of Ibadan and University College Hospital, Ibadan, Ibadan, Nigeria; Department of Ophthalmology, College of Medicine, University of Ibadan and University College Hospital, 200212 Ibadan, Ibadan, Nigeria;Purpose:
To determine the preoperative visual acuity of cataract patients over a 10-year period in a tertiary facility as a means of auditing the cataract surgical services.
Methods:
A retrospective study of patients with age-related cataracts who had cataract surgery performed between January 2007 and December 2016 at the University College Hospital, Ibadan. Systematic random sampling and probability proportionate to size were used to recruit a representative sample. Information on sociodemographic characteristics, preoperative visual acuity, ocular and systemic comorbidities were retrieved and analysed.
Results:
Of the 499 patients studied, males were 268 (53.7%) and their mean age was 67.69 (±9.51) years. The predominant visual acuity was hand motion 184 (36.9%) and yearly mean preoperative visual acuity was in the range of 0.0037–0.04 decimal.
Conclusion:
The mean preoperative visual acuity of patients in this facility did not change over the 10-year study period. Mean value of preoperative visual acuity remained within the range of blindness and did not improve over the decade. This could either be a reflection of visual impairment at which our patients seek care or an indication of the range of visual acuities at which surgeons are willing to offer cataract surgery in our environment. This trend has negative implications on the burden of cataract blindness as it reflects poor coverage of surgery for other levels of visual impairment due to cataract.