|LETTERS TO THE EDITOR
|Year : 2018 | Volume
| Issue : 7 | Page : 1048-1049
Commentary on “Intravitreal dexamethasone implant for management of treatment-naïve retinal vein occlusion”
Associate Consultant, Vitreo-Retinal Surgery Ophthalmology, Medanta Hospital, Gurgaon, Delhi, India
|Date of Web Publication||25-Jun-2018|
Associate Consultant, Vitreo-Retinal Surgery Ophthalmology, Medanta Hospital, Gurgaon, Delhi
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Bansal M. Commentary on “Intravitreal dexamethasone implant for management of treatment-naïve retinal vein occlusion”. Indian J Ophthalmol 2018;66:1048-9
|How to cite this URL:|
Bansal M. Commentary on “Intravitreal dexamethasone implant for management of treatment-naïve retinal vein occlusion”. Indian J Ophthalmol [serial online] 2018 [cited 2020 May 30];66:1048-9. Available from: http://www.ijo.in/text.asp?2018/66/7/1048/234983
Treatment of macular edema has been revolutionized by the introduction of optical coherence tomography and intravitreal injections over the last decade and a half. Intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections, initially introduced for neovascular Age-related macular degeneration have made a significant contribution toward alleviating macular edema due to diabetes and retinal vein occlusion (RVO). Corticosteroid injections have been used in the past. Introduction of intravitreal dexamethasone implant (IDI) just under a decade back, has added to the armamentarium of the ophthalmologist. It provides sustained released dexamethasone, typically over a period of 3–6 months, reducing the need for frequent injections. However, it is accompanied by the increased chances of intraocular pressure (IOP) rise, and progression/onset of cataract.
The article “The efficacy of intravitreal dexamethasone implant as the first-line treatment for retinal vein occlusion-related macular edema in a real-life scenario” addresses an important question. In this article, the authors have shared their experience with the use of IDI in eyes with macular edema secondary to RVO, which have not received any other prior treatment. While most literature and current practice focuses using IDI as alternate therapy in eyes not responding to anti-VEGF injections, the question addressed here is, whether IDI can be offered as a primary therapy.
To address this question, let us list out certain salient points. Mechanism of macular edema is multi-factorial. While most anti-VEGF agents target limited factors, steroid agents have anti-angiogenic, anti-inflammatory, and anti-proliferative effects. The incidence of adverse events with IDI, ranges from 6% to 32% for cataract (needing surgery), and 5%–36% for IOP rise (>25 mm Hg needing IOP lowering drugs)., None of these studies mention need for glaucoma surgery for IOP management. To add, these adverse events, occur at a lower frequency with IDI, as compared to other steroid injections. This could possibly be due to different ocular distribution  and pharmacological profile  of various corticosteroids. In all series, management of IOP rise was by IOP lowering medication, and cataract was very safely managed with cataract surgery. The results and inferences from previously published literature are in agreement with this study, and our own experience. In comparison, the ocular safety profile of anti-VEGF injections is generally favorable. However, they have been reported to be associated with increased risk of cerebrovascular accidents  and myocardial infarction (MI).
A sustained release drug, decrease number of injections and hence burden of therapy. When using dexamethasone implant, overall cost of treatment may actually come down for the patient, when compared to most anti-VEGFs (except off-label use of bevacizumab) as frequent injections are not required. Often there may be patient/family anxiety associated with repeated injections. Lesser visits to operating room/injection room, with use of sustained release drug help alleviate patient anxiety.
Therefore, as a concluding remark, it might be most prudent to offer the choice of treatment to the patient. Allowing them to make an informed choice. Explaining risks and benefits of each. Certain existing patients' conditions, as mentioned above may not be suitable, for example, existing glaucoma for steroid use, and known history of transient ischemic attacks, stroke, and MI for anti-VEGF use. For the rest, it may be most wise to give the choice to the patient and make an informed choice ourselves as well, as treating surgeons.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Simsek M, Citirik M, Ozates S, Ozkoyuncu D. The efficacy of intravitreal dexamethasone implant as the first-line treatment for retinal vein occlusion-related macular edema in a real-life scenario. Indian J Ophthalmol 2018;66:831-6.
] [Full text]
Dugel PU, Capone A Jr., Singer MA, Dreyer RF, Dodwell DG, Roth DB, et al.
Two or more dexamethasone intravitreal implants in treatment-naïve patients with macular edema due to retinal vein occlusion: Subgroup analysis of a retrospective chart review study. BMC Ophthalmol 2015;15:118.
Eter N, Mohr A, Wachtlin J, Feltgen N, Shirlaw A, Leaback R, et al.
Dexamethasone intravitreal implant in retinal vein occlusion: Real-life data from a prospective, multicenter clinical trial. Graefes Arch Clin Exp Ophthalmol 2017;255:77-87.
Kiddee W, Trope GE, Sheng L, Beltran-Agullo L, Smith M, Strungaru MH, et al.
Intraocular pressure monitoring post intravitreal steroids: A systematic review. Surv Ophthalmol 2013;58:291-310.
Thakur A, Kadam R, Kompella UB. Trabecular meshwork and lens partitioning of corticosteroids: Implications for elevated intraocular pressure and cataracts. Arch Ophthalmol 2011;129:914-20.
Nehmé A, Lobenhofer EK, Stamer WD, Edelman JL. Glucocorticoids with different chemical structures but similar glucocorticoid receptor potency regulate subsets of common and unique genes in human trabecular meshwork cells. BMC Med Genomics 2009;2:58.
Avery RL, Gordon GM. Systemic safety of prolonged monthly anti-vascular endothelial growth factor therapy for diabetic macular edema: A systematic review and meta-analysis. JAMA Ophthalmol 2016;134:21-9.
Zarbin MA. Anti-VEGF agents and the risk of arteriothrombotic events. Asia Pac J Ophthalmol (Phila) 2018;7:63-7.