1. What should we inject? Low dose or high dose intravitreal triamcinolone for macular edema.
A Paul, C Louize,S Shafquat
Dudley Hospitals NHS Foundation Trust
Russells Hall Hospital Dudley UK
Reference
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BACKGROUND
RESULTS
RESULTS
Triamcinolone acetonide (TA) is a corticosteroid suspension that has been used in periocular and intraocular injections for the treatment of cystoid macular oedema secondary various pathologies. Intravitreal Triamcinolone Acetonide has also shown favorable results in the treatment of diffuse diabetic macular oedema.1 The rationale behind their use lies in their ability to inhibit the arachidonic acid pathway, of which prostaglandin is a product. Corticosteroids may also downregulate the production of vascular endothelial growth factor (VEGF). Different doses varying from about 2 mg to about 20 mg TA have been employed thus far.
Discussion
PURPOSE OF THE STUDY
All the patients with long standing diabetic macular
oedema, and had undergone at least three episodes of macular laser treatment without improvement in the condition. Hauser D did not find 4 mg dose more effective than 2 mg dose.2 Kim JE had similar results, with significant number of patients showing raised IOP of more than 10 from the baseline. 19% Vs 41 %.3 (Our study showed 25%). Rate of increased of intraocular pressure after IVTA has been reported between 31% and 40% in the literature.4 Risk increases with increased number of IVTA injections. Beck RW found significant cataract progression in patients receiving 4 mg dose as compared to 1 mg.
Score study report 5 showed better visual outcomes with 1 mg dose (odds of 5 times greater of achieving gain of 15 letters or more) than only observation or 4 mg dose in patients with visual loss associated with macular edema in perfused CRVO.5 Our patient had ischemic CRVO with 9 months old edema and did not show any visual improvement although OCT showed marked improvement anatomically. Score study report 6 found no significant gain in vision as compared to Grid photocoagulation, 1 and 4 mg dose IVTA in patients with BRVO.5 We used 2 mg IVTA in conjunction with laser therapy and patient with ischemic BRVO gained 10 letters on the EDTRS chart.
To investigate benefits and side effects of low dose intravitreal triamcinolone acetonide for symptomatic macular edema and compare it with high dose intravitreal triamcinolone acetonide injection.
MATERIAL & METHODS
A retrospective and prospective study of patients who underwent intravitreal injection of 2 mg triamcinolone acetonide for macular edema of varying etiology ( Post operative CMO, refractory diabetic macular edema, retinal vein occlusion and wet ARMD). Main outcome measures were visual acuity and improvement of macular edema on OCT. We looked at complications related to the injection (endophthalmitis, uveitis, cataract formation and raised intraocular pressure).
Patients were followed up at 1 week, 3 months and 6 months.
OCT: 9/12 (75%) patient showed reduction in thickness on OCT after 4 weeks of injection. In 33% of patients, foveal OCT thickness reduced to < 180 micron. The improvement lasted for more than 3 months. 3 showed no improvement.
CONCLUSIONS
We found in our cohort that for short term, 2 mg dose of triamcinolone is as efficacious as higher doses used in other studies in improving vision, reducing macular thickness, with the added benefit of possible reduction in steroid related side effects. Endophthalmitis remains the most serious complication of IVTA, but the risk is extremely low with good aseptic precautions.
RESULTS
Twelve eyes were included (7 Males and 5 Females). Mean age was 68.5 years (range 47 to 85 years). Minimum duration of macular edema was 5 months (range 2 weeks to 30 weeks). No correlation was found between the duration of macular edema and anatomical and functional improvement after IVTA.
BCVA: 8 patients (66%) noticed improvement in LOGMAR visual acuity. Marked improvement of more than 20 letters was noted in all the three patients with post operative CMO . Four patients with refractory diabetic maculopathy and one BRVO patient improved by 5 to 15 letters. The improvement lasted for more than 3 months.
REFERENCES
Complications
IOP Raised IOP > 21mm Hg was noted in 1 patient at 1 week and 2 patients at 4 weeks follow up (25%). Only one of them needed anti glaucoma drops. Progression of cataract was noted in 2 patients.
No other injection related complications noted (e.g., endophthalmitis, retinal detachment, retinal tear, vitreous haemorrhage or macular haemorrhage)
Dose Dependent Effects of Intravitreal Triamcinolone Acetonide on Diffuse Diabetic Macular Edema. Joon Sung Bae et al. Korean J Ophthalmol June; 23(2): 80–85.
ISIS-DME: a prospective, randomized, dose-escalation intravitreal steroid injection study for refractory diabetic macular edema. Kim JE, et al. Retina, May 2008, vol./is. 28/5(735-40).
Intravitreal triamcinolone for diabetic macular edema: comparison of 1, 2, and 4 mg. Hauser D, et al. Retina, June 2008, vol./is. 28/6(825-30
Intraocular pressure alterations following intravitreal triamcinolone acetonide. Rhee DJ, et al. Br J Ophthalmol Aug; 90(8):
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 Standard Care vs Corticosteroid for Retinal Vein Occlusion (SCORE) study report 5 and 6. Scott IU, et al. SCORE Study Research Group. Archives of Ophthalmology, September 2009, vol./is. 127/9( ), ; and September 2009, vol./is. 127/9( ), ;