Sir,
We believe that the review by Talany et al1 needs further discussion. The authors wrote ‘there are no substantial recommendations or guidelines regarding the modification of warfarin and new oral anticoagulations (NOACs) prior to any type of ocular surgery. The decision to withhold, modify, or continue anticoagulation should be individualized’. The fact is that there are no standard recommendations whether to discontinue anticoagulant or antiplatelet agents in these patients when ocular surgery is performed, although it is generally agreed that cataract surgery,2 and intravitreal injections are low-risk procedures for bleeding complications and discontinuation or modification is not needed.
Recent evidence-based guidelines recommend continuation of anticoagulants in patients undergoing cataract surgery provided that the international normalized ratio is in the therapeutic range and that aspirin be discontinued perioperatively only if the risk of bleeding outweighs its potential benefit.3
Although the 2009 meta-analysis found that, patients taking warfarin while undergoing cataract surgery had a three-fold increase of bleeding events compared to those not on warfarin, but the vast majority of bleeding events were self-limited, typically hyphemae or subconjunctival hemorrhage.4 There was no evidence that continuing warfarin had a negative impact on postoperative visual acuity. Recent meta-analysis, including seventeen randomized controlled studies, reported no differences in the risk of substantial intraocular bleeding (that is, hyphema, vitreous hemorrhage, subretinal hemorrhage, and suprachoridal hemorrhage) between NOAs and other antithrombotic drugs.5
In summary, several studies show a higher incidence of subconjunctival hemorrhage in patients undergoing cataract surgery while taking antiplatelet or anticoagulant medication, but the available data do not show an increase in sight-threatening complications or decreased postoperative visual acuity.
Footnotes
The authors declare no conflict of interest.
References
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