Year : 2022 | Volume
: 34 | Issue : 2 | Page : 182--183
Effect of cataract surgery on wet age-related macular degeneration activity
Consultant Ophthalmologist and Phacosurgeon, Comtrust Eye Hospital, Kozhikkode, Kerala, India
Dr. K Husna
Comtrust Eye Hospital, Kozhikkode, Kerala
|How to cite this article:|
Husna K. Effect of cataract surgery on wet age-related macular degeneration activity.Kerala J Ophthalmol 2022;34:182-183
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Husna K. Effect of cataract surgery on wet age-related macular degeneration activity. Kerala J Ophthalmol [serial online] 2022 [cited 2023 Feb 2 ];34:182-183
Available from: http://www.kjophthal.com/text.asp?2022/34/2/182/355034
Karesvuo P, Elbaz U, Achiron A, Hecht I, Kaarniranta K, Tuuminen R. Effect of cataract surgery on wet age-related macular degeneration activity. Acta Ophthalmol. 2022 Feb; 100(1):e262-e269. doi: 10.1111/aos. 14864. Epub 2021 Apr 10. PMID: 33838002.
Age-related macular degeneration (AMD) is the leading cause of irreversible legal blindness in people 65 years or older. With the continued aging of the world population, AMD is expected to grow in prevalence with the number of estimated cases expected to reach 288 million by 2040. The use of anti-vascular endothelial growth factor (anti-VEGF) therapies has revolutionized the care for patients with neovascular AMD.
There has been much debate and conflicting evidence as to whether cataract surgery causes progression of AMD. The timing of cataract surgery among wet AMD patients is a matter of debate. Cataract reduces retinal visibility and hinders treatment, in addition to reducing vision. At the same time, there is concern regarding the progression of AMD following cataract surgery. There is a lack of consensus regarding the protocol treatment of wet AMD patients undergoing cataract surgery. This study aimed to investigate whether cataract surgery in wet AMD patients affects its course and the relationship to how it influences the clinical outcomes.
The study was a registry-based retrospective cohort study of consecutive cataract surgeries performed on wet age-related macular degeneration (ARMD) patients at Helsinki University Hospital, Helsinki, Finland. The study included patients who underwent uncomplicated cataract surgery between January 2014 and December 2018. Data were collected from the operating room management system (BCB Medical, cataract database, Turku, Finland). For inclusion, all patients were required to have documentation on the type of postoperative medical treatment received, systemic medication, and anti-VEGF treatment for wet ARMD before laterality matched uncomplicated cataract surgery. The primary outcome of the study was to evaluate the change in central subfield macular thickness (CSMT) after surgery and at 1year. Secondary outcomes were the changes in visual acuity, anti-VEGF treatment interval, macular status between the preoperative and postoperative phase, and the correlation between the CSMT change and the cumulative number of anti-VEGF injections before surgery.
The anti-VEGF treatment protocol used was the fixed-treat-and-extend protocol. Either bevacizumab 1.25 mg or aflibercept 2 mg was used as an anti-VEGF drug. Patients received three monthly anti-VEGF injections at baseline, and the treatment interval was lengthened accordingly: Three consecutive injections at a 6-week interval, two consecutive injections at an 8-week interval, one injection at a 10-week interval, and finally reaching the maximum 12-week interval. If the disease showed activation, the treatment intervals were shortened.
The cataract surgical technique used in this study was phacoemulsification with a 2.4–2.75mm clear corneal incision. A single-piece acrylic monofocal intraocular lens (IOL) was implanted into the capsular bag. Postoperative medications were steroids, non-steroidal anti-inflammatory drugs (NSAIDs), or a combination of both. The duration of anti-inflammatory treatment was 3 weeks in almost all cases.
All patients underwent a comprehensive ophthalmic examination and optical coherence tomography (OCT) analysis. Foveal thickness, CSMT defined as mean thickness in the central 1000 μm diameter area and maximum thickness in the central 1000 μm diameter area were recorded by spectral-domain OCT (SD-OCT). Follow-up 30-frame SD-OCT scans were performed with AutoRescanTM software (spectral-domain OCT (SD-OCT, Heidelberg Eye Explorer Version 184.108.40.206 and HRA/SPECTRALIS R Viewing Module Version 220.127.116.11, Heidelberg Engineering GmbH, Heidelberg, Germany). The subtyping of wet AMD was done at the time of diagnosis with fluorescein angiography (FA) and/or indocyanine green angiography. Macular status on OCT scans of all cases was evaluated masked by a medical retina specialist.
Visual acuity was examined using a standard Snellen chart with the best-corrected refraction and using decimal numbers and converted to logarithms of the minimum angle of resolution (logMAR) for statistical purposes.Best-corrected visual acuity (BCVA) and OCT parameters were obtained at different time points, including at the time of wet AMD diagnosis, and within 18weeks before and after surgery depending on the timing of out-patient clinic visits according to a fixed- Treat-and-Extend Regimen (TER) protocol and patients' treatment intervals, that is anti-VEGF injections may have been given in between the surgery and the latest OCT scans.
One hundred and eleven eyes of 111 patients with a mean age of 78.9 ± 5.6 were included in the study. Cataract surgery did not significantly influence the incidence of hemorrhages, pigment epithelial detachment, intraretinal fluid, or subretinal fluid when comparing macular status at the surgery to that at the first postoperative visit and 1year.
At the time of cataract surgery, CSMT was 280.1 ± 75.0 μm, with a postoperative CSMT of 268.6 ± 67.6 μm (p = 0.001) and a 1-year CSMT of 265.9 ± 67.9 μm (p = 0.003). The BCVA in logMAR units was 0.70 ± 0.46 (Snellen equivalent median and interquartile range (IQR); 0.30, 0.125–0.40) prior to cataract surgery, and improved to 0.39 ± 0.40 (Snellen equivalent median and IQR; 0.50, 0.32–0.80) postoperatively (p < 0.001), and to 0.33 ± 0.34 (Snellen equivalent median and IQR; 0.50, 0.32–0.80) at 1year (p < 0.001). After cataract surgery, foveal thickness increased >30% (from preoperative values) in only three out of the 111 eyes (2.7%). The CSMT change postoperatively inversely correlated with the CSMT level prior to surgery.
CSMT level before surgery significantly correlated with CSMT change postoperatively, whereas the cumulative number of anti-VEGF injections, anti-VEGF treatment interval, and presence of subretinal and intraretinal fluid at cataract surgery did not.
The effects of baseline factors like the existence of diabetes, systemic drugs like anticoagulants, calcium channel blockers, statins, and topical anti-inflammatory medications along with age and gender were examined for association with CSMT change postoperatively or at 1 year and the anti-VEGF treatment burden after surgery. None of these factors were associated with any clinical outcomes related to wet AMD first or 1-year postoperative visits, except for thinner CSMT at the first postoperative visit in those taking statins.
A relatively small cohort size (N = 111) and the short follow-up time are the primary limitations of this study. Another limitation of this study is that the time between pre- and postoperative out-patient visits and cataract surgery was not standardized because of the retrospective setting, which means that the macular edema may fluctuate depending on the cataract surgery and treatment intervals. On the other hand, the use of just a single standardized time point, such as a postoperative visit 4 weeks after surgery, would lack the information on macular status just before the next anti-VEGF administration. In Treat-and-Extend Regimen (TER) protocol, all out-patient visits were predetermined based on the disease activity and the current treatment interval.
The authors concluded that the timing of cataract surgery in wet AMD patients should be adjusted according to patients' needs. There is no justification to support delaying surgery until dry macula has been achieved. Surgery should, therefore, not be postponed for these considerations in patients who require it.
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Conflicts of interest
There are no conflicts of interest.