Comparison of intravitreal versus posterior sub-Tenon's capsule injection of triamcinolone acetonide for diffuse diabetic macular edema.
OBJECTIVE
To compare the safety and efficacy of intravitreal versus posterior Sub-Tenon's capsule injection of triamcinolone acetonide for diffuse diabetic macular edema.


METHODS
Prospective, double-masked, randomized controlled trial.


METHODS
Twelve patients (24 eyes) with bilateral diffuse diabetic macular edema.


METHODS
One eye of each patient was randomly assigned to receive a single 4-mg triamcinolone acetonide intravitreal injection and the fellow eye to receive a 40-mg triamcinolone acetonide posterior Sub-Tenon's capsule injection.


METHODS
Changes in visual acuity and central macular thickness obtained using optical coherence tomography were measured during a 6-month follow-up. Potential treatment complications were monitored, including increases in intraocular pressure (IOP) and cataract progression.


RESULTS
Both intravitreal and Sub-Tenon's capsule injections of triamcinolone acetonide resulted in significant but transient improvements in central macular thickness. The mean (+/-standard deviation [SD]) central macular thickness in eyes with intravitreal injection was significantly thinner than in the Sub-Tenon's capsule-injected eyes at 1 month (226.8+/-41.7 microm and 431.5+/-165.8 microm, respectively; P = 0.002) and 3 months (242.3 +/- 93.9 microm and 364.7+/-78.2 microm, respectively; P = 0.005) after triamcinolone acetonide injection. The mean visual acuity (logarithm of the minimum angle of resolution) in the intravitreally injected eyes was significantly better than in the Sub-Tenon's capsule-injected eyes at 3 months post injection (0.832+/-0.293 and 1.107+/-0.339, respectively; P = 0.004). Intraocular pressure did not show any significant difference between the 2 forms of triamcinolone acetonide delivery at any follow-up visit, and no eyes had IOPs >25 mmHg.


CONCLUSIONS
The findings from our study neither advocate nor support the use of corticosteroids for the treatment of diabetic macular edema, but do imply that both intravitreal and Sub-Tenon's capsule injections of triamcinolone acetonide may be equally tolerated, with short-term performance clearly favoring the intravitreal (4 mg) more than the SBT capsule (40 mg) route for the anatomic and functional aspects of improvement tested in this investigation.
Cardillo
José A
JA
Hospital de Olhos de Araraquara, Araraquara, São Paulo, Brazil. hospitaldeolhos@uol.com.br
Melo
Luiz A S
LA
Costa
Rogério A
RA
Skaf
Mirian
M
Belfort
Rubens
R
Souza-Filho
Acácio A
AA
Farah
Michel E
ME
Kuppermann
Baruch D
BD
D000328:Adult; D000368:Aged; D003238:Connective Tissue / Q000187:drug effects; D003930:Diabetic Retinopathy / Q000188:drug therapy* / Q000503:physiopathology; D004311:Double-Blind Method; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage*; D006801:Humans; D007267:Injections / Q000379:methods; D007429:Intraocular Pressure / Q000502:physiology; D008269:Macular Edema / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012449:Safety; D041623:Tomography, Optical Coherence; D014222:Triamcinolone Acetonide / Q000008:administration & dosage*; D014792:Visual Acuity / Q000502:physiology; D014822:Vitreous Body / Q000187:drug effects
D005938:Glucocorticoids; D014222:Triamcinolone Acetonide