الفهرس 
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Abstract
Intravitreal triamcinolone acetonide has increasingly been used in treatment of macular edema of variety of causes (12) .
Macular edema is retinal thickening within 2 disc diameter (2 DD) of the center of the macula . Retinal thickening or hard exudates with adjacent retinal thickening that threaten or involve the center of the macula is considered to be clinically significant macular edema (52).
Macular edema caused by a variety of causes such as diabetic macular edema which is swelling of the retina in diabetes mellitus due to leaking of fluid from blood vessels within the macula,macular oedema secondary to CRVO or BRVO which cause increase in the venous pressure transmitted to perifoveal capillaries causing macular edema(26).
In aqueous humor and in silicone oil, triamcinolone acetonide has been found up to 1.5 years after the intravitreal injection (26).
We aimed in this study to assess the complications of intravitreal injecton of triamcinolone acetonide in the treatment of macular edema caused by different etiologies among patients attending suez canal university hospital to reduce the side effects and complications associated with this procedure.
Reported side effect included secondary ocular hypertension leading in some patients to secondary chronic open-angle,catarct formation,retinal breaks vitreous haemorrhage and post-injectoin infectious or sterile endophthalmitis(24).
This study revealed that approximately 7 (15%) of the patients developed elevation of IOP by ≥ 15 mmHg after intravitreal Triamcinolone acetonide injection we assumed that the cause was due to reduction in the facility of aqueous outflow, trabecular and anterior uveal meshwork tissue which have a high concentration of corticosteroid receptors, the mechanism of action for IOP elevation may be also due to an increase in extracellular matrix proteins, a decrease in the phagocytic activity of the trabecular endothelial cells, and a decrease in prostaglandins that regulate aquous outflow(24), as well, triamcinolone intravitreal injection may caused IOP elevation due to mechanical obstruction of the trabecular meshwork by the steroid particles or its vehicle(24).
Eleven (11) patients, which represented 23% of all patients suffered from mild subconjunctival heamorrhage may be caused due to accidentaly trauma to small subconjunctival vessels .
No one developed retinal detachment, lens injuries, cataract or endophthalmitis. This may be due to the injection were done under aseptic conditions in the ophthalmological surgical theatre using operative microscope by skillful hands.
In the current study, the mean initial pressure was 14.3 mm Hg (range 11 to 18 mm Hg, SD ± 1.8 mm Hg). A mean pressure increas at day 2 was 16.9 mmhg (range 13 to 25 mmhg,SD±2.5).A mean pressure increase at day 10 was 18.3mm Hg (range 13 to 40 mm Hg, SD ± 7.06 mm Hg).A mean pressure increase at day 30 was 18.1 (range 12 to 37 mmhg,SD± 6.7 mmhg) .The greatest increase was 24 mmHg.
In Jost et al study(62),mean baseline IOP was 15.3 mmHg with SD± of 2.4,mean maximum IOP was 22.3 mmHg (ranging from 11- 64 mmHg) with S.D of 7.0.Mean IOP increase was 7.0 mmHg,no patients suffered from retinal detachment, lens injuries, cataract or endophthalmitis,comparing these results with our current study it shows that the results are not near to “Jost et al.” study with different IOP range during the follow-up that is may be due to the high dose (20 mg) of intravitreal T.A and also the long term follow-up of his study.
In Smithen et al study we found that mean baseline IOP was 14.9 mmHg (ranging from 7-20 mmHg) with SD± of 2.9 , mean maximum IOP was 22.9 mmHg (ranging from 14-42 mmHg) with SD± of 6.0,mean IOP increase was 8 mmHg (60) and no patients suffered from retinal detachment, lens injuries , cataract or endophthalmitis.With this study the incidence of mean IOP rise is near we got in our results.
Repeated intravitreal injection for three times were performed in another study by Jonas et al. (2) , after the first injection: mean baseline IOP was 16.7 mmHg with SD± of 3.5 ,mean maximum IOP is 20.7 mmHg with S.D of 4.2 mmHg (ranging from 12-28 mmHg). after 2nd injection: mean baseline was 16.0 mmHg with SD± of 3.8 ,mean maximum baseline IOP was 21.4 mmHg with S.D of 5.8 mmHg (ranging from 10-36 mmHg).After 3rd injection: mean baseline was 18.0 mmHg with SD± of 0,mean maximum IOP was 26.3 mmHg with SD± of 8.4 (ranging from 21-36 mmHg),no eyes suffered from retinal detachment, vitreous heamorrahge , lens injuries , cataract or endophthalmitis in the 3 repeated injections.The incidence of mean IOP rise increase after the 2nd and 3rd injection results, it indicates a cumulative effect of intravitreal injection of T.A.
In another study by Audren et al study(61) showed mean baseline IOP was 18.2 mmHg with SD± of 3.2 , mean maximum IOP was 20.8 mmHg with S.D of 4.6mmHg, mean increase IOP is 2.6 mmHg, the incidence of mean IOP rise is near to our study because they used only patients with diabetic macular edema , no other complications showed in this study.
Some results reported to be a little higher than our study as found in Jonas et al study(63) after 1st injection: 41% IOP exceeded more than 21 mmHg, after 2nd injection: 54% IOP exceeded more than 21 mmHg, after 3rd injection; 50% IOP exceeded more than 21 mmHg, this result was due to high dose of TA injected,no eyes suffered from retinal detachment, vitreous heamorrahge , lens injuries , cataract or endophthalmitis.
Bakri et al study(25) revealed that mean pressure increas was 5.0 mmHg found in 48.8% And 10.0 mmHg found in 27.9%.Results are higher than the previous study because they followed-up less number of patients .No other cmplications reported in this study.
In another study of Jonas et al study(3) a mean pressure increas was 5.0 mmHg in 45% , 10.0 mmHg in 22.4% ,15.0 mmHg found in 11.0% and 20.0 mm Hg found in 5.5%,no eyes suffered from retinal detachment, vitreous heamorrahge , lens injuries , cataract or endophthalmitis, results are near to the results of our study.
There are limitations of our study one of them is the fact that baseline pressure was based on a single measurement taken prior to the day of injection future studies might include diurnal or serial pressure testing to better determine the true baseline pressure.
the follow up of patients by other methods such as optic disc changes, visual field if the vision not affected much and the use of OCT may need to be considered in the future studies as an indicator for glaucomatous damage.