Intravitreal steroids are a versatile pharmacologic tool in our armamentarium, used to suppress inflammatory mediators and reduce vascular permeability.1-3 Among these agents, triamcinolone acetonide occupies a unique role in vitreoretinal surgery. Beyond its established anti-inflammatory effects, it serves as a valuable intraoperative adjunct by enhancing visualization of the vitreous and facilitating critical surgical maneuvers.4 Understanding when and how to use intravitreal triamcinolone during surgery can enhance visualization, facilitate surgical maneuvers, and improve operative efficiency.
Visualization During Vitrectomy
FDA-approved indications for triamcinolone acetonide injectable suspension 40 mg/mL (Triesence; Harrow) include treatment of sympathetic ophthalmia, temporal arteritis, uveitis, and ocular inflammatory conditions unresponsive to topical corticosteroids.5 It is also approved for visualization during vitrectomy, and may be used as a surgical adjunct during pars plana vitrectomy to identify the vitreous.4 Diluted intravitreal triamcinolone adheres to and stains vitreous white, providing a visible scaffold for precise surgical work.
An observer-masked study of 60 patients undergoing pars plana vitrectomy found up to 4 mg of preservative-free triamcinolone produced a mean visualization score of 3.7 following instillation vs 0.5 prior to instillation (P<.0001). Most posterior-segment structures (83.3%) were rated as clearly delineated compared with 0% prior to instillation.4
Triamcinolone staining may be used multiple times during vitrectomy. It is particularly helpful to distinguish the posterior vitreous cortex during critical surgical maneuvers, including the following:
- Inducing a posterior vitreous detachment. Staining confirms that the vitreous has been fully elevated and reveals any residual adhesion (Video 1).
- Identifying and addressing residual peripheral vitreous. In retinal detachment cases, diluted triamcinolone acetonide injectable suspension 40 mg/mL may be injected near the end of the procedure to facilitate more complete vitreous removal, potentially reducing the risk of proliferative vitreoretinopathy and subsequent retinal redetachment (Video 2).
- Internal limiting membrane (ILM) visualization and peeling. Triamcinolone may aid visualization of the ILM and can serve as an alternative when standard chromovitrectomy dyes such as indocyanine green, trypan blue, or brilliant blue G are unavailable.
- Posterior-capsule rupture with vitreous prolapse into the anterior chamber. A small injection through a clear corneal or limbal incision to stain the vitreous strands allows complete and confident removal.
At the close of a vitrectomy case, residual triamcinolone can safely remain in the eye. A small residual depot may provide early postoperative anti-inflammatory coverage.6
Practical Considerations
Dilution is the most critical variable in intraoperative triamcinolone use. Injecting undiluted triamcinolone acetonide injectable suspension 40 mg/mL creates a dense particle suspension inside the eye that briefly impairs visualization. Dilution ratios with balanced salt solution may vary; however, I prefer an 8:1 to 12:1 ratio. Also, although 3:1 to 4:1 dilutions are not harmful, in my hands the particle load impacted efficiency. At higher dilution ratios, the staining remains effective and the time required to clear excess steroid is substantially reduced.
Injection technique also matters. It is best to inject a small amount, assess coverage, and add more only as needed. The goal is sufficient vitreous staining with minimal clearing time.
Regarding needle selection, triamcinolone can be injected through a 27-gauge to 30-gauge needle for office-based procedures. For intraoperative use in the context of vitrectomy, the drug is introduced directly into the surgical field.
Formulation Matters
The labeling on preserved triamcinolone acetonide (Kenalog; Bristol Myers-Squibb) explicitly states it is not for intraocular use. However, during an extended shortage of triamcinolone acetonide injectable suspension 40 mg/mL, many surgeons turned to off-label use of Kenalog out of necessity (see “The Return of Triesence”). Beyond a medicolegal risk, preserved triamcinolone has clinical disadvantages, including retinal toxicity and inflammation from the benzyl alcohol.7 Additionally, variability in triamcinolone crystal size across non–FDA-approved formulations (both preserved and compounded) has been associated with unpredictable and severe IOP elevations.8-9
The Return of Triesence
Originally FDA-approved in 2007, triamcinolone acetonide injectable suspension 40 mg/mL (Triesence; Harrow) was on the FDA’s Drug Shortage List for more than 5 years and unavailable in the United States for more than 2 consecutive years beginning around 2022. In October 2024, triamcinolone acetonide injectable suspension 40 mg/mL was relaunched following a global effort to rebuild the supply chain and requalify the manufacturing process to current Good Manufacturing Practice standards.17 A 5-year strategic supply agreement with the primary manufacturer provides structural commitment to continued availability.
Triesence carries a permanent J-code (J3300) for office-based injection. In April 2025, CMS granted transitional pass-through reimbursement status, providing separate payment in ambulatory surgical centers and hospital outpatient departments for up to 3 years,18 making it the only preservative-free synthetic corticosteroid with separate reimbursement across all traditional clinical care settings.
Triamcinolone acetonide injectable suspension 40 mg/mL has uniform crystal sizing, producing a more predictable pharmacokinetic response and substantially more manageable IOP. This formulation is the only FDA-approved, preservative-free triamcinolone indicated specifically for intraocular use, eliminating concerns about off-label exposure.
Mechanisms and Other Indications
Although visualization during surgery is a unique attribute of intravitreal triamcinolone, it is also an important therapeutic option for selected retinal diseases. Corticosteroids exert an anti-inflammatory effect through multiple pathways relevant to retinal disease, including downregulation of the proinflammatory cytokines IL-6, IL-8, and TNF-α; suppression of VEGF expression; inhibition of leukocyte adhesion via ICAM-1; and direct stabilization of tight junctions to reduce vascular permeability and macular edema.10 This multipotent mechanism distinguishes corticosteroids from anti-VEGF agents, which are known to target a single pathway.
In clinical practice, several scenarios stand out as particularly well suited to intravitreal triamcinolone. One indication is postoperative cystoid macular edema after cataract surgery or vitrectomy that responds initially to a potent topical agent such as difluprednate but cannot be tapered, or in which drops are cost prohibitive or poorly tolerated. Unlike topical agents, which rarely achieve intraocular concentrations sufficient to resolve macular edema,11 intravitreal delivery places the drug directly at the site of pathology.
A second key indication is diabetic macular edema (DME) with a suboptimal response to anti-VEGF therapy. After 3 or 4 injections without meaningful improvement, switching to or adding intravitreal triamcinolone can help identify patients with a steroid-responsive inflammatory phenotype.12,13 The inflammatory component of DME is well established, and the broader mechanism of corticosteroids may explain the response in cases where anti-VEGF monotherapy has failed.
Although steroids are often viewed as a distant second-line option to anti-VEGF therapy, the DRCR.net Protocol I study found that pseudophakic patients treated with intravitreal triamcinolone plus prompt laser achieved visual acuity outcomes comparable to those treated with ranibizumab-based regimens.14 Importantly, pseudophakic patients in the triamcinolone arm required a median of 3 injections during the first year compared with 8 to 9 injections in the ranibizumab arms. For pseudophakic patients—and for phakic patients willing to accept and manage cataract progression—the durability advantage of triamcinolone may represent a meaningful clinical distinction. These findings are supported by additional studies demonstrating the efficacy of intravitreal corticosteroids for DME and other causes of macular edema, with IOP elevation remaining the most common, though generally manageable, adverse event.15-16
Conclusion
Intravitreal triamcinolone occupies a distinctive position in vitreoretinal practice. Few agents in our armamentarium address intraoperative visualization, inflammatory macular edema, anti-VEGF nonresponse, and uveitic disease in a single pharmacologic profile. The side effects of IOP elevation and cataract progression are real, but they are predictable, monitorable, and in most patients manageable without incisional intervention. They should inform patient selection and postoperative care, not serve as a blanket reason for deferral. For retina specialists who have drifted away from intravitreal triamcinolone during years when a preservative-free, FDA-approved formulation wasn’t available, now is a reasonable time to re-examine the evidence and reintegrate it where the clinical case is clear. RP
References
1. Tamura H, Miyamoto K, Kiryu J, et al. Intravitreal injection of corticosteroid attenuates leukostasis and vascular leakage in experimental diabetic retina. Invest Ophthalmol Vis Sci. 2005;46(4):1440-1444.
2. Sivaprasad S, McCluskey P, Lightman S. Intravitreal steroids in the management of macular oedema. Acta Ophthalmol Scand. 2006;84(5):579-585.
3. Sarao V, Veritti D, Boscia F, Lanzetta P. Intravitreal steroids for the treatment of retinal diseases. Scientific World J. 2014;2014:989548.
4. Dyer D, Callanan D, Bochow T, et al. Clinical evaluation of the safety and efficacy of preservative-free triamcinolone (triesence [triamcinolone acetonide injectable suspension] 40 mg/mL) for visualization during pars plana vitrectomy. Retina. 2009;29(1):38-45.
5. TRIESENCE (triamcinolone acetonide injectable suspension) 40 mg/mL [Prescribing Information]. Harrow IP, LLC; 2023.
6. Takamura Y, Shimura M, Katome T, et al. Effect of intravitreal triamcinolone acetonide injection at the end of vitrectomy for vitreous haemorrhage related to proliferative diabetic retinopathy. Br J Ophthalmol.2018;102(10):1351-1357.
7. Couch SM, Bakri SJ. Use of triamcinolone during vitrectomy surgery to visualize membranes and vitreous. Clin Ophthalmol. 2008;2(4):891-896.
8. Kleinman ME, Westhouse SJ, Ambati J, et al. Triamcinolone crystal size. Am J Ophthalmol.2010;117(8):P1654-1654.E4.
9. Zacharias LC, Lin T, Migon R, et al. Assessment of the differences in pharmacokinetics and pharmacodynamics between four distinct formulations of triamcinolone acetonide. Retina. 2013;33(3):522-531.
10. Ciulla TA. Corticosteroids for diabetic macular edema. Review of Ophthalmology. 2015. Accessed March 25, 2026. https://www.reviewofophthalmology.com/article/corticosteroids-for-diabetic-macular-edema-2015
11. Schwartz SG, Scott IU, Stewart MW, Flynn HW Jr. Update on corticosteroids for diabetic macular edema. Clin Ophthalmol. 2016;10:1723-1730.
12. Ciulla TA, Pollack JS, Williams DF. Visual acuity outcomes and anti-VEGF therapy intensity in diabetic macular oedema: a real-world analysis of 28 658 patient eyes. Br J Ophthalmol. 2021;105(2):216-221.
13. Patil NS, Mihalache A, Hatamnejad A, Popovic MM, Kertes PJ, Muni RH. Intravitreal steroids compared with anti-VEGF treatment for diabetic macular edema. Ophthalmol Retina. 2023;7(4):289-299.
14. Diabetic Retinopathy Clinical Research Network; Elman MJ, Aiello LP, Beck RW, et al. Randomized trial evaluating ranibizumab plus prompt or deferred laser or triamcinolone plus prompt laser for diabetic macular edema. Ophthalmology. 2010;117(6):1064-1077.e35.
15. Scott IU, Ip MS, Van Veldhuisen PC, et al; SCORE Study Research Group. A randomized trial comparing the efficacy and safety of intravitreal triamcinolone with standard care to treat vision loss associated with macular edema secondary to branch retinal vein occlusion: the SCORE study report 6. Arch Ophthalmol.2009;127(9):1115-1128.
16. Chang AA, Haitao L, Zhu M, et al. Safety and efficacy of intravitreal preservative-free triamcinolone acetonide (Triesence) for macular edema. J Ocul Pharmacol Ther. 2015;31(9):436-441.