Ophthalmology Surgery Edition

by Catherine Joseph

What is Ophthalmology Surgery?

An ophthalmologist is a medical doctor specializing in the comprehensive medical and surgical care of the eyes and vision^1,2. However, an ophthalmic surgeon is more specialized than a traditional ophthalmologist. They perform surgery to correct refractive errors, glaucoma, and cataracts as well as diagnose and treat medical conditions that affect the eye¹. There are about 10 sub-specialties under ophthalmology surgery such as ocular oncology, cataract and refractive surgery, glaucoma and so much more ³.

Figure 1: Glaucoma surgery ⁴

Figure 2: Ophthalmology surgery in process ⁵

Notable Journals in the Field

Journal in the Spotlight: Journal of Ophthalmic Surgery

Journal of Ophthalmic Surgery is an open-access, peer-reviewed publication that showcases cutting-edge research by physicians and ophthalmologists, focusing on advanced diagnostics and treatments for conditions like macular degeneration, diabetic retinopathy, ocular melanoma, glaucoma, and retinal vascular disease. Content is freely available under the Creative Commons Attribution License. The journal accepts a wide range of article types, including original research, reviews, case reports, and more, ensuring high quality through rigorous evaluation by international experts⁶.

Article Reviews

Glaucoma: Trabeculectomy vs Repeat shunt surgery?

Glaucoma is a serious eye condition that can lead to blindness if not treated. One of the major causes of glaucoma is an increase in the intra-ocular pressure. The Ahmed glaucoma valve (AGV) is a small device that is implanted in the eye to help drain excess fluid, which can reduce pressure on the optic nerve and prevent vision loss⁷.

Figure 3: Pathophysiology of glaucoma⁸

The AGV is often used for people with severe glaucoma who have tried other treatments without success. However, it’s important to know that even with the AGV, there’s a chance that it might not work as well as hoped. Studies have shown that about 40% of people who have the AGV implanted may need additional treatment within five years. This study illustrates which surgical procedure is best after a failed Ahmed glaucoma valve.

Figure 4: Surgical procedure of Ahmed glaucoma valves⁹

To figure this out a quasi-experimental study was done, which included patients with failed AGV implants at least six months after the implantation of the device. A failed AGV was defined as unacceptable intraocular pressure (IOP) on two consecutive visits (one to two weeks apart) despite using maximum tolerable glaucoma medications. Patients were recruited from a hospital in Iran over 4 years. To determine which surgical treatment the patients will undergo, the state of their conjunctiva was used. Those with mobile conjunctiva, an open angle, and favourable ocular condition with no significant scars would undergo a trabeculectomy and those not suitable for the trabeculectomy were scheduled for re-implantation of the Ahmed glaucoma valves.

Figure 5: Trabeculectomy (description)¹⁰

In glaucoma studies, the surgery is deemed successful as having an IOP of 21 mmHg or less, along with at least a 20% reduction in IOP⁷. The study, however, uses 3 additional success criteria. Criteria A: IOP of 18 mmHg or less with more than a 20% reduction, Criteria B: IOP of 15 mmHg or less and more than 25% reduction, Criteria C: IOP of 12 mmHg or less with more than 30% reduction. Furthermore, the surgery was considered unsuccessful if the patient lost the ability to perceive light or needed further glaucoma surgery.

The study included 48 patients: 22 underwent trabeculectomy and 26 had repeat AGV surgery. Of these, 10 in the trabeculectomy group and 14 in the re-AGV group had primary congenital or juvenile glaucoma with a history of childhood trabeculectomy. Notably, a history of trabeculectomy or trabeculectomy in childhood did not affect the success of trabeculectomy in this study⁷.

In the TRAB group, the average intraocular pressure (IOP) decreased from 30.5 ± 7.5 mmHg at the start to 8.5 ± 2 mmHg after one year (P < 0.001). In the re-AGV group, the IOP dropped from 32.6 ± 7.1 mmHg to 14.4 ± 4.3 mmHg over the same period (P < 0.001). The TRAB group consistently had lower IOP than the re-AGV group at 3, 6, 9, and 12 months⁷.

The study showed that both TRAB and re-AGV are effective in lowering IOP after a failed AGV implant in patients with good conjunctival quality and mobility. However, TRAB was more effective than re-AGV in controlling IOP and reducing the need for glaucoma medications at all time points. The stricter success criteria further highlighted the superiority of trabeculectomy⁷. Lower IOP is particularly beneficial for eyes with advanced glaucoma and a failed AGV. Importantly, there was no significant difference in the overall complication rates between the two groups (P = 0.92)⁷.

Acknowledgments

This article was brought to you by the TSSS Research Sub-Committee of 2024. The principal author of the piece is Catherine Joseph, with chief editor Ivan Möller overseeing quality.

References

1. Ophthalmic surgeons: What they do (& do you need one?) [Internet]. NVISION Eye Centers. 2020 [cited 2024 Sep 2]. Available from: https://www.nvisioncenters.com
2. Ophthalmology [Internet]. ACS. [cited 2024 Sep 2]. Available from: https://www.facs.org/for-medical-professionals/education/programs
3. Ophthalmic surgery [Internet]. Rcsi.com. [cited 2024 Sep 2]. Available from: https://www.rcsi.com/surgery
4. Image of a Glaucoma Surgery with a Leica Ophthalmic Microscope [Internet]. Leica Microsystems; 2023. Available from: https://www.leica-microsystems.com
5. DragonImages. Doctor performing eye surgery in modern clinic [Internet]. iStock (Getty Images); 2016. Available from: https://www.istockphoto.com
6. Ronald EP Frenkel PIM, editor. Journal of Ophthalmic Surgery. Vol. 2578. Scholars.Direct
7. Einollahi N, Doozandeh A, Sharifipour F, Hassanpour K, Rezaei J, Radmehr H, et al. Failed Ahmed glaucoma valves: trabeculectomy versus repeat shunt surgery. BMC Ophthalmol [Internet]. 2024;24(1). Available from: http://dx.doi.org/10.1186/s12886-024-03610-7
8. Astorino A Jr. Glaucoma [Internet]. Astorino & Associates Eye center; Available from: https://www.astorinoeyecare.com
9. Pepakayala V. Surgical implantation of the Ahmed glaucoma valve [Internet]. ResearchGate; 2015. Available from: https://www.researchgate.net/publication/
10. Trabeculectomy [Internet]. Southeast Texas Ophthalmology; Available from: https://www.setxglaucoma.com