***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: OBJECTIVE To evaluate prospect ively the efficacy and safety of 1 intravitreal injection of 4 mg of triamcinolone acetonide for refractory diffuse diabetic macular edema . DESIGN Interventional case series . PARTICIPANTS Fifteen patients with bilateral diabetic macular edema unresponsive to laser photocoagulation . In all patients , one eye received the injection , and the other served as a control . INTERVENTION Intravitreal injection of 4 mg of triamcinolone acetonide under subconjunctival anesthesia . MAIN OUTCOME MEASURES The main outcome measure was central macular thickness ( CMT ) at 1 , 3 , and 6 months , measured by optical coherence tomography . Secondary outcomes were Early Treatment Diabetic Retinopathy Study ( ETDRS ) scores , intraocular pressure , and cataract progression . RESULTS In this preliminary report , we give the results for 12 patients who had a follow-up of at least 3 months . Seven of them were followed up for 6 months . Before injection , CMT was 509.6+/-143.5 microm ( mean + /- st and ard deviation [ SD ] ) in injected eyes , versus 474.4+/-82.6 microm in control eyes . Four weeks after injection , it was 207.3+/-44.2 microm in injected eyes and 506.7+/-122.4 microm in control eyes ( P<0.001 , bilateral Wilcoxon test for paired sample s ) , and after 12 weeks , 207+/-96.7 microm and 469.3+/-117.6 microm , respectively ( P = 0.005 ) . The difference between the CMTs of injected and control eyes was no longer significant at 24 weeks because of the recurrence of macular edema in 5 of 12 injected eyes . Before triamcinolone injection , the ETDRS score was 47.8+/-13 ( mean + /- SD ; range , 28 - 66 ) in injected eyes , versus 51.9+/-14.6 ( range , 31 - 71 ) in control eyes . Twelve weeks thereafter , the corresponding values were 52.7+/-10.8 ( range , 34 - 70 ) and 50.8+/-14.3 ( range , 29 - 69 ) , respectively , and at 24 weeks , 54.7+/-7.6 ( range , 47 - 68 ) and 50.6+/-18.4 ( range , 28 - 71 ) . At no time was the difference between the ETDRS scores for injected and control eyes significant . In 6 of the 12 injected eyes , intraocular pressure exceeded 25 mmHg , and was controlled by topical medication . CONCLUSION Intravitreal injection of triamcinolone effectively reduces macular thickening due to diffuse diabetic macular edema , at least in the short term . Further studies are required to demonstrate that it provides visual benefit PURPOSE To compare the effectiveness of posterior sub-Tenon 's infusion ( STi ) and intravitreal injection ( IVI ) of triamcinolone acetonide ( TA ) for treatment of refractory diffuse diabetic macular edema . METHODS Thirty-six phakic diabetic patients with refractory diffuse diabetic macular edema were prospect ively enrolled . Patients r and omly received either 40 mg STi or 4 mg IVI of TA .  Comprehensive ophthalmic evaluation was performed at baseline and 1 , 2 , 4 , 8 + /- 1 , 12 + /- 2 and 24 + /- 2 weeks after treatment . Macular morphologic changes detected by optical coherence tomography and visual acuity , intraocular pressure , and lens status were evaluated . RESULTS Twenty-eight patients ( 28 eyes ) completed the 24-week study . Central macular thickness was significantly reduced in the IVI group when compared with the STi group at 2 , 4 , 8 , 12 , and 24 weeks after treatment ( P < 0.01 ) . Mean visual acuities ( in logarithm of the minimum angle of resolution [ logMAR ] ) at week-4 , -8 , and -12 follow-up examinations were significantly higher in the IVI group ( 0.74 , 0.75 , and 0.82 , respectively ) when compared with the STi group ( 0.88 , 0.88 , and 0.90 , respectively ; P < 0.01 ) . A significant change from baseline in mean intraocular pressure ( mm Hg ) was seen at weeks 4 ( + /-3.21 ) and 8 ( + /-3.35 ) in STi the group ( P < 0.01 ) , and at week 8 ( + /-2.78 ) in the IVI group ( P < 0.05 ) . No patient had cataract progression during the study . CONCLUSIONS Although the number of patients and length of follow-up in this preliminary study were limited , the changes in central macular thickness and visual acuity observed after treatment suggest that IVI TA may be more effective than STi for the management of refractory diffuse diabetic macular edema . Further studies are needed to confirm these preliminary findings OBJECTIVE The epidemiological risk factors for the different forms of diabetic macular edema ( focal or diffuse ) are not differentiated in the literature . In the present study , the objective was to determine which risk factors influence the appearance of focal or diffuse macular edema . RESEARCH , DESIGN , AND METHODS : A 4-year prospect i ve study in a population of Type II diabetic patients ( NIDDM ) in three groups , the first with 29 patients with diffuse diabetic macular edema ( Group A ) , the second with 32 patients with focal macular edema ( Group B ) , and the third with 32 patients with diabetic retinopathy but without diabetic macular edema ( Group C ) ; the three groups were selected on the basis of sex , age , and duration of diabetes with similar patterns . We studied the following risk factors : treatment of diabetes mellitus by insulin , presence of diastolic blood hypertension , presence of microalbuminuria or diabetic nephropathy , levels of HbA1c , type of diabetic retinopathy , presence of previous panretinal photocoagulation , and levels of triglycerides and fractions of cholesterol . RESULTS In discriminant analysis and in order of importance , the epidemiological risk factors for Group A were the following : presence of panretinal laser , diastolic blood hypertension , diabetic nephropathy , and insulin treatment ; for group B , the risk factors were the following : insulin treatment , presence of diastolic blood hypertension , and high levels of glycated haemoglobin ( HbA1c ) ; and for group , C the risk factors were the following : diastolic blood hypertension , insulin treatment of diabetes , and high levels of HbA1c . CONCLUSIONS In the present study , the group of patients with focal macular edema were epidemiologically similar to the group of patients with diabetic retinopathy without macular edema , the group of patients with diffuse macular edema were epidemiologically different OBJECTIVE To evaluate the clinical outcome of an intravitreal injection of triamcinolone acetonide as treatment of diffuse diabetic macular edema . PARTICIPANTS This prospect i ve , interventional , clinical case series study included 20 patients ( 26 eyes ) who received an intravitreal injection of 25 mg of triamcinolone acetonide for treatment of diffuse diabetic macular edema . Mean + /- SD follow-up time was 6.64 + /- 6.10 months . The study group was compared with a control group of 16 patients who underwent macular grid laser coagulation .  MAIN OUTCOME MEASURES Visual acuity and intraocular pressure . RESULTS In the study group , visual acuity improved significantly ( P<.001 ) , from 0.12 + /- 0.08 at baseline to a maximum of 0.19 + /- 0.14 during follow-up . Seventeen ( 81 % ) of 21 eyes with a follow-up period of more than 1 month had improved visual acuity . In the control group , visual acuity did not change significantly . In the study group , intraocular pressure increased significantly ( P<.001 ) , from 16.9 + /- 2.5 mm Hg to a mean maximal value of 21.3 + /- 4.7 mm Hg , and decreased significantly ( P = .03 ) to 17.7 + /- 4.7 mm Hg at the study 's end . CONCLUSION Intravitreal injection of 25 mg of triamcinolone acetonide may be beneficial for improving visual acuity in patients with clinical ly significant diffuse diabetic macular edema Aim : To evaluate the effect of different doses of intravitreal triamcinolone acetonide on diffuse diabetic macular oedema . Methods : The prospect i ve , r and omised , double masked , clinical interventional study included 27 eyes ( 27 patients ) with diffuse diabetic macular oedema . They were r and omly divided into three study groups receiving an intravitreal injection of filtered triamcinolone acetonide of about 2 mg ( n = 8 eyes ) , 5 mg ( n = 10 ) , or 13 mg ( n = 9 ) , respectively . Dosage measurement was performed before filtration . Mean follow up was 6.6 ( SD 2.4 ) months ( 3–12 months ) . Main outcome measures were visual acuity and intraocular pressure . Results : Maximal increase in visual acuity was significantly ( p = 0.046 ; 95 % CI : 0.032 to 2.99 ; r = 0.38 ) correlated with the dosage of intravitreal triamcinolone acetonide . Additionally , the duration of the effect of intravitreal triamcinolone acetonide increased significantly with the dosage of intravitreal triamcinolone acetonide ( r = 0.45 ; p = 0.014 ) . Increase in intraocular pressure during follow up was statistically not significantly associated with the dosage used ( p = 0.77 ) . Conclusions : In patients with diffuse diabetic macular oedema receiving intravitreal triamcinolone acetonide , treatment response may last longer and be more pronounced with a dosage of 13 mg than in lower doses of 5 mg or 2 mg . Triamcinolone acetonide induced increase in intraocular pressure may not be markedly associated with the dosage used PURPOSE To report on visual outcome of patients receiving intravitreal triamcinolone acetonide for treatment of diffuse diabetic macular edema . DESIGN Prospect i ve , comparative clinical interventional study . METHODS SETTING Institutional . patient population : The study included 25 consecutive patients ( 50 eyes ) with bilateral diabetic macular edema . Intervention procedure : Unilateral intravitreal injection of about 20 mg triamcinolone acetonide into the eye ( study group ) more severely affected by diabetic maculopathy . The contralateral eyes served as control group . Mean follow-up was 7.1 + /- 4.1 months . MAIN OUTCOME MEASURE Visual acuity , intraocular pressure . RESULTS In the study group , visual acuity increased significantly ( P < or = .001 ) by 3.0 + /- 2.6 Snellen lines to a peak at two to six months after the injection , and decreased significantly ( P = .001 ) towards the end of follow up . At the end of follow-up , visual acuity was higher , not significantly ( P = .18 ) higher , than at baseline . An increase in visual acuity was found in 23 eyes ( 92 % ) . In the control group , differences between visual acuity at baseline and at any of the re-examinations during follow-up were not significant ( P > .10 ) . In an intra-individual inter-eye comparison , gain in visual acuity was significantly ( P < .05 ) higher in the injected eyes , for the measurements obtained up to four months after injection . CONCLUSIONS Intravitreal triamcinolone acetonide may temporarily increase visual acuity in eyes with diabetic macular edema PURPOSE The aim of this study was to examine the visual outcome of patients receiving an intravitreal injection of triamcinolone acetonide ( TA ) as treatment of diffuse diabetic macular edema ( DDME ) . METHODS This prospect i ve , placebo-controlled , r and omized , clinical interventional study included 40 eyes ( 38 patients ) with DDME , with 28 ( 70 % ) eyes r and omized to treatment and 12 ( 30 % ) eyes r and omized to receive a placebo injection . Thirty-six ( 36 ) ( 90 % ) eyes completed the 3-month study visit , and 32 ( 80 % ) eyes completed the 6-month study visit . The treatment group received an intravitreal injection of approximately 20 mg of TA . RESULTS Visual acuity increased significantly ( P < 0.001 ) in the study group by 3.4 + /- 2.5 Snellen lines . In the control group , visual acuity did not change significantly ( P = 0.07 ) during follow-up . Difference in change of best visual acuity was significant ( P < 0.001 ) between both groups . At 3 months after baseline , 11 ( 1 
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Increased intraocular pressure and cataract formation were side effects requiring monitoring and management .
RCTs included in this review suggest that steroids placed inside the eye by either intravitreal injection or surgical implantation may improve visual outcomes in eyes with persistent or refractory DME .
Since the studies in our report focused on chronic or refractory DME , the question arises whether intravitreal steroids therapy could be of value in other stages of DME , especially the earlier stages either as st and alone therapy or in combination with other therapies , such as laser photocoagulation